IUPAC NOMENCLATURE OF COMPOUNDS CONTAINING MORE …theuranium.org/content-images/organic-nomenclature-III.pdf · associated with greater number of functional groups is taken as the

CHAPTER-III

IUPAC NOMENCLATURE OF COMPOUNDSCONTAINING MORE THAN ONE FUNCTIONAL GROUP

Based on whether a group can be used as suffix in the root name(as parent compound)or as prefix before the parent name(as branches), functional groups belong to the followingthree types.TYPE A: Groups which can be used only as prefix i.e as a substituent:

Name of the group General formulaalkyl R-alkoxy RO-alkylsulfanyl(alkylthio) RS-halo X-nitro NO

2-

alkenyl R CH CH

alkynyl R C C

phenyl C6H

5-

cycloalkyl cyclopropyl, cyclobutyl etc.These 9 types of groups are used only as branches of the main chain. In otherwords

they are used only as prefixes to the parent compounds. They are never used as suffixes ofthe root words to form the parent compounds. Therefore, they do not have any priority orderamong them. Lowest set of locants rule is applicable to all of them to choose the directionof numbering the longest chain.CAUTION: The order in which these groups are placed in the above table is arbitrary.No group gets any precedence over any other group to fix up the direction of numbering.They all obey the lowest set of locants rule.TYPE B: Functional groups which can only used as suffixes to form the parent compound.

Name of the group structure

Alkene

Alkyne

* These groups(ene and yne) enjoy the same priority. Do not mistake their relativeplacement in the above table as priority order. The locants of enes and ynes commonlyobey the lowest set of locants rule. If the sets of locants for enes and ynes are samein the two opposite directions of numbering the principal chain, in that case only enegets precedence over yne. Otherwise they enjoy the same priority and obey only thelowest set of locants(for ene and yne) rule.

* When enes and ynes are present in the longest carbon chain alongwith other functionalgroups(type-C), then enes and ynes appear as co-suffixes with the seniormost functionalgroup. Therefore such groups are used as suffixes only. This may not be mistakenfor alkenyl and alkynyl groups which are used as prefixes. All these will be madeclear very soon.

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TYPE C: Functional Groups which can be used both as a suffix to form the parentcompound or prefix to form a substituent

When a compound contains more than one functional groups belonging to type Cthen, the one having the highest priority(called the principal functional group) will be used assuffix to form the parent compound and all others will be used as prefixes(i,e as substituents)of the parent compounds. Note that ene and yne functions belonging to type B groups appearalways as co-suffixes with the highest priority group in the parent name. This thing will beclarified with a lot of examples later.

PRIORITY ORDER AMONG TYPE (C) FUNCTIONAL GROUPS

The following table gives the relative priorities or precedences of type-C functionalgroups in decreasing order. The terms given in the prefix column are the names of thefunctional groups when they are used as substituents(prefixes) and the terms given in thesuffix column are the suffixes used with the root words to form the parent compounds.

Name of group structure prefix suffix

carboxylic acid C

O

OH carboxy -oic acid(carboxylic acid)

sulfonic acid -SO3H sulfo sulfonic acid

acid anhydride C

O

O C

O- -oic anhydride

esterC

O

OR'alkoxycarbonyl -oate

(carboxylate)

acid halide C

O

X halocarbonyl-oyl halide(carbonyl halide)

acid amide C

O

NH2aminocarbonyl

-amide(carboxamide)

nitrile C N cyano -nitrile(carbonitrile)

aldehyde C

O

Hoxo

(formyl)-al

(carbaldehyde)

ketone C

Ooxo -one

alcohol -OH hydroxy -olthiol -SH sulfanyl/mercapto -thiolamines -NH

2/-NHR/-NR

2amino -amine

Nomenclature of Organic Compounds

Note that the suffixes given within parentheses in the above table are used only whenthe carbon atom of the functional group is not included in the longest carbon chain. The usualsuffixes given are used when the carbon atoms of the groups are included in the longestchain. Formyl is used as prefix(substituent) when the carbon atom of -CHO group is excludedfrom the principal carbon chain. This will be made more clear soon.

General rules for naming compounds containing more than 1 functional group:

1. The longest carbon chain giving the lowest locant to the highest priority group is foundout first for determining the parent compound. The C-C double bond or triple bondis(are) accommodated in the longest chain(old rule). All other functional groupsappear as branches(prefixes) which are written first followed by the name of parentcompound. The ene or yne appear as co-suffixes with the highest priority group.

Example:

CH38

7

6

5

Cl

4

3

2

1

O

OH

OHO

O

CH3

N

5-chloro-2-cyano-4-hydroxy-7-methoxy-6-oxooct-3-en-1-oic acid OR5-chloro-2-cyano-4-hydroxy-7-methoxy-6-oxooct-3-enoic acidIn this molecule, there are 7 functional groups including the ene function. The functional

group having highest priority(see above table) is carboxylic acid(-COOH). So the parentcompound is a carboxylic acid(oic acid), not alcohol(ol), nitrile or a ketone(-one). The carboxylcarbon is numbered 1 as per rule. All functional groups other than the highest prioritygroup(COOH) excepting the ene function are used as substituents and the names given inthe prefix column in the above table are used for naming these substituents. Ene is used asa co-suffix before the suffix of the principal functional group(oic acid). The locant of ene andoic acid are placed before the respective suffixes(ene and oic acid). The last letter e of eneis dropped as it cannot face a vowel in -oic acid. The locant of oic acid(1) is usually notwritten. You can write the name of the parent compound as oct-3-en-1-oic acid or oct-3-enoic acid, the latter being the preferred name.

Example:

H

5

O

4

3

2

1

O

O

OH

OH

Cl

CH3

ethyl 4-chloro-3-hydroxy-2-(hydroxymethyl)-5-oxopentanoate

��

In this molecule, there are four functional groups namely ester, two hydroxy and aldehydegroups. Since ester group has the highest priority among them, the parent compound is anester(alkanoate). The alkyl group of the alcohol part is written first as usual. This is followedby the substituents of the longest alkanoate chain. The terminal aldehyde carbon(C-5) is a partof the main chain, so the prefix oxo is used(not formyl). At C-2, the branch is hydroxymethyland at C-3 the branch is hydroxy while at C-4 the branch is chloro. Since the first word ishydroxy in both the groups, the simple(or shorter) branch hydroxy is written first followed bythe complex(longer) branch hydroxymethyl.

2. If the longest chain of equal lengths are available on two directions, then the oneassociated with greater number of functional groups is taken as the principal carbonchain for naming the parent. If the number of functional groups is same in both thechains, then the chain bearing the higher priority functional group is taken as thecorrect longest chain.

4

3

2

1

O

OH

O H

5

OH 6

NH2

6-amino-5-hydroxy-4-(2-oxoethyl)hexanoic acid

In the above example -COOH is the principal functional group and so the parentcompound is alkanoic acid. Longest chain of six carbon atoms is available on both thedirections from C-4. The chain containing two functional groups(-OH and -NH

2) is taken as

the correct longest chain. Note that although the other chain bears a higher priority group(-CHO), still it is not considered as the principal chain for naming. The complex branch atC-4 is 2-oxoethyl because the terminal aldehyde group(C=O) is included in the main branchethyl and hence is prefixed by oxo(not formyl). The name formylmethyl can be used in placeof 2-oxoethyl but the latter is the preferred name of the group.

NH2

OOH

NH2

65 4 3 2

1

2-amino-5-methyl-6-oxohex-3-ynamide

6

5 4 3 2

NH2

1

O

OHO

NH2

O

H

2,6-diamino-5-formyl-6-oxohex-3-ynoic acid

In first case aldehyde carbon is included in the longest chain, not CH3 carbon. Note

that the longest chain(C-6) is available in both the directions from C-5. The longest chainwhich has greater number of functional groups attached to it is taken as the correct longestchain. That is why aldehyde carbon was taken in the main chain and the suffix oxo is usedfor it, not formyl. Note that when aldehyde group remains as a part of the longest chain, itwill be expressed by prefix oxo. However if it remains outside the main chain, it will beexpressed by prefix formyl. Note thate yne has appeared as co-suffix with amide and the


last letter e of yne has been deleted as it cannot face a vowel in the word -amide. The suffixof amide(1) has also been deleted.

In the second case, between aldehyde and amide function the latter has greaterpriority and so it is included in the principal chain, not aldehyde. For aldehyde, the prefixformyl is used as it is outside the principal chain. For the amide, both the term oxo for theC=O and amino for the NH

2 groups were used in alphabetical order. Note that when derivatives

of carboxylic acids such as ester, amide and acid chloride are included in the main chain andthose groups are not highest priority groups in the chain, the prefixes used for them are asfollows.

functional group prefixes usedamide both amino and oxo (not aminocarbonyl)acid chloride both chloro and oxo (not chlorocarbonyl)ester both alkoxy and oxo (not alkoxycarbonyl)

Example:

OH

O

Cl6

5 43

2

1

2-ethyl-4-formylhexanoyl chloride

OH

O

O

CH3O

4

32

1

4-methoxy-2-methyl-4-oxobutanoic acid

In the first case, aldehyde function has been excluded in the longest chain and theprefix formyl has been used for that. In the second case, since carboxylic acid has higherpriority over ester function, the parent becomes alkanoic acid. Since ester carbon is includedin the main chain, two prefixes- methoxy and oxo have been used and arranged in alphabeticorder.

OCH3

OSO3H

4-methoxy-3-methyl-4-oxobutane-2-sulfonic acid

43

2

1

In this case, sulfonic acid has higher priority than ester, so the parent compound isalkanesulfonic acid. Since ester carbon is included in the longest chain, two prefixes namelymethoxy and oxo are used as explained before. Sulfonic acid group gets the lowest locant.

Example:

CH31 2

3

O

4

5

6

CH37

OHBrCl

H2N OH

3-aminopropan-1-ol(not 3-hydroxypropan-1-amine

12

3

4-bromo-2-chloro-6-hydroxyhept-5-en-3-one

��

In the 1st case, keto function(one) has highest priority, hence the compound is aketone. So the carbonyl carbon has got the lowest locant(3). All other groups appear assubstituents except the ene function which appears as co-suffix with the principal function-one. Note that here also the last letter e of ene has been deleted as it cannot face a vowel.In this case, both the locants of ene(5) and one(3) have to be written for them separatelyunlike aldehydes, carboxylic acid and its derivaties in which the suffix 1 is usually deleted.

In the 2nd case, since OH has the higher priority over NH2 group, the compound is

an alcohol(not amine). So the lowest locant has been assigned to the OH group. The NH2

function appears as a branch having prefix amino.

Example:

CNOH

I

1

2345

6

1'2'

3'

2-(2-hydroxy-1-methylpropyl)-3-iodo-4-methylhexanenitrile

2-chloro-5-bromohexane(wrong)2-bromo-5-chlorohexane

Br

Cl

In the first case longest carbon chain is C-6. The other direction would have givenshorter chain(C-5). Since nitrile is the principal functional group, it is an alkanenitrile. Thebranch at C-2 is complex and is named as usual by following the rules for naming complexbranches.In the second case, the set of locants are same on either direction(2,5) and hence thealphabetical priority of bromo decides the direction of numbering.

PRESENCE OF CARBON-CARBON MULTIPLE BONDS IN THE CHAIN(OLD RULE):

If the compound contains one or more carbon-carbon double or triple bonds alongwitha functional group of type C, then the chain bearing both the functional group and maximumnumber of double and triple bonds will be considered for naming the parent compound eventhough it may not be the longest continuous carbon chain. Look at this example.

CH3

5

4

3

2

1

O

OH

CH26

CH3

CH34

3

2

1

2

1

O

O CH3

CH3

34

CH25

5-isobutylhex-5-enoic acid isopropyl 2-(but-2-enyl]penta-2,4-dienoate

In the first example, the longest chain could have been C-8 starting from COOHcarbon. But the chain used for naming the parent compound is C-6, because in that chain theC=C is included. In the second example, the longer chain could have been C-6 starting fromthe carboxylate carbon. But the chain used for naming the parent compound is C-5, becausein that chain two C=C bonds are included while in chain containing C-6, one C=C is included.


Since there are two double bonds in the chain the multiplying prifex di is used with ene. Thee of ene is dropped as usual. The root word pent is suffixed with letter ‘a’ to make penta.

Note that, if the compound does not contain a double bond or a triple bond, thenlongest continuous carbon chain bearing the principal functional group is considered for namingthe parent compound. That longest chain may not also directly bear other functional groupsof lower priorities.

OH

3

2

1

4

3

2

1

O

OH

CH25

4-(3-hydroxypropyl)pent-4-enoic acid

CH36

5

4

3

2

1

O

OH

COOEt

4-(ethoxycarbonyl)hexanoic acid

In the first example, the chain containing C=C is selected for naming the parent(C-5),while the side chain containing OH group(a functional group having lower priority) has beenexcluded from the principal chain used for naming the parent. In the second example,COOEt(Et=ethyl)group has been excluded from the principal chain as the longest chain is C-6.

Conclusion: Maximum number of double and triple bonds are to be included in theprincipal chain even if this chain may not necessarily be the longest.

NEW IUPAC RECOMMENDATION FOR NAMING COMPOUNDSCONTAINING C-C MULTIPLE BONDS ALONGWITH HIGHER PRIORITYGROUP(S) -(TYPE C GROUPS):

Like the naming for simple alkenes and alkynes, IUPAC has recommended provisionallysimilar rules for naming compounds containing both type C functional group(s) as well asC-C multiple bonds.

1. The longest continuous carbon chain containing the highest priority group is selectedirrespective of whether C-C multiple bond remains within the chain or not. The doubleand triple bond may be excluded from the longest chain if situation arises. In sucha case, branch containing the multiple bonds are named as alkenyl, alkynyl or alkylideneor the like.

2. The direction of numbering should be such that the highest priority group gets thelowest locant.Let us rename the first three compounds given before.

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CH38

7

6

5

4

3

2

1

OH

OCH2CH3

CH36

5

4

3

2

1

O CH3

CH3O

CH2

7-methyl-5-methyleneoctanoic acid isopropyl 2-(prop-2-enylidene)hex-4-enoate

OH

7

6

5

4

3

2

1

O

OH

CH2

7-hydroxy-4-methyleneheptanoic acidIn the first case, the C=C is excluded from the longest chain and the parent is octanoic acidand the branch is methylene which is attached to C-5. Since methylene is a longer term thanmethyl, it is placed after methyl.

In the second example, the longest chain is C-6 and hence the parent is hexenoicacid. The branch becomes a alkenylidene group. Note that for a bivalent group idene issuffixed to yl. Since there is a C=C at C-2 of the branch, the root becomes prop-2-enyl andhence the whole bivalent group becomes prop-2-enylidene. The locant of oate(1) has beendeleted from the name of parent compound while ene appears as co-suffix with oate withits locant 4.

In the third example, the C=C has been excluded from the longest chain of C-7.=CH

2 group becomes the methylene branch at C-4 and hydroxy being the branch at C-7.

IMPORTANT: The longest chain containing the highest priority group always gives theparent compound whether or not this chain accommodates C-C double(s) or triplebond(s). The students are advised to use the new rules with caution as these are notofficially published.

SAQ III.1: Give the IUPAC names of the following compounds from their line structures.

(i)OH

(ii) COOH

(iii) OOH

(iv)

NH2

OH

Cl

Br

(v) CN

O

H (vi)

O

OH

SO 3 H

(vii) CH3

COOHO

O

CH3

CH3

CH3

CHO

CH3

(viii) Cl

O

SO3H


(ix)

OH

(x) H

S NH2

(xi)

SH

CH3

OH

(xii)

CH3

S CH3

CH3

OH

CH3

(xiii)

CH3

O

CH3

O

OH

(xiv) CH3

CH3

OCH3 CH3

CH3

NITRILE GROUP ALONGWITH A HIGHER PRIORITY GROUP:(EXCEPTION TO GENERAL RULE)

When -CN group is present in a compound along with another group having higherpriority, the carbon of -CN group is excluded from the principal chain used for naming theparent compound. This is valid both when CN carbon remains as a part of the longest chainas well as when it remains outside the longest chain. If CN remains in the main chain, thenthat carbon is not numbered as it is excluded from the principal chain giving the parentcompound. This is an exceptional case unlike the case of aldehyde, carboxylic acid and otherderivatives of carboxylic acid -CN group is always excluded from the principal chainand appears as a branch with the prefix cyano. See these examples.

C

O

OHN

2 13

4

4-cyano-2-methylbutanoic acidCN O

O12

3

45

6

sec-butyl 5-cyano-2-methylpentanoate

In the first case, the CN group is excluded from the principal chain of 4 carbon atomsalthough it is directly attached to it. In the second case also CN is excluded at C-5. Notethat if the group would have been -CHO(aldehyde) or other derivative of carboxylic acidinstead of CN in the second example, carbon atom of that functional group would have beenincluded in the principal chain, not CH

3 carbon. But, since the group is -CN, it is to be

excluded and CH3 group is to be included. This is an exceptional treatment given to cyanide

group by IUPAC.

SAQ III.2: Name the following.

(i)CH3

N

O

NH2

CH3

(ii) O

H

N

CH3

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POLYENES, POLYYNES AND ENYNES:

When a molecule contains more than one C=C double bonds, it is called a diene,triene, tetraene, pentaene and so on. depending on the number of double bonds present andin general, it is called a polyene. Similarly, when a molecule contains more than one triplebond, it can be a diyne, triyne, tetrayne etc. and in general, called polyynes. When amolecule contains both double and triple bonds, it is generally called enynes.

Rules for nomenclature:

(1) The correct longest carbon chain is one which contains maximum number ofdouble and triple bonds(OLD RULE).

(2) The multiplying prefixes di, tri, tetra, penta etc. are used with ene and yne dependingon the number of double and triple bonds present in the longest chain

(3) Lowest set of locants for enes and ynes is considered while choosing the direction ofnumbering.

(4) If the sets of ene/yne locants are same on either direction, then ene gets the lowestlocant.

(5) If the compound is a polyene or a polyyne(not an enye), and the sets of ene/ynelocants are same on either side, then lowest set of locants for the sustitutents decidesthe correct direction of numbering.

(6) The root word, prop, but, pent, hex etc. is suffixed with the letter a to make it propa,buta, penta, hexa etc. if they are followed by the terms di, tri, tetra etc. This isbecasue a consonant in the root (prop, but, pent etc) cannot face another consonantin di, tri etc. in the suffix. So by rule the letter a is suffixed to the root word. Forexample-butadiene, hexatriyne etc.not buttriene, hextriene etc.

(8) The locants of enes and ynes are prefixed before them. For example hexa-1,3,6-triene, buta-1,3-diyne etc.

(9) After the root word, ene comes first and then yne.

(10) When ene faces a yne, the last letter e of ene is dropped, as y is taken to be a vowelfor naming purpose. For example- hex-1-en-3-yne.

(11) If the branches contain double and triple bonds then they are named as alkenyl andalkynyl as explained before (but-2-enyl, prop-1-ynyl etc.).

(12) If chain of equal length containing same total number of enes and ynes compete forlongest chain selection, then the chain containing maximum number of enes gives thecorrect longest chain.

(13) If same number of total enes and ynes are present in two or more chains, then chaincontaining maximum number of carbon atoms gives the correct longest chain.

See these examples and again study the rules for a better understanding.


6

5

43

21

3-methylhexa-1,4-diene

110

98

76 5

4

32

5-ethyl-7,9-dimethylundeca-4,6-diene

11

76

54

3

2

1

4-isopropyl-6-methyl-3-propylhept-5-en-1-yne

1

23

4

but-1-en-3-yne

1

2

3

4

56

hexa-1,3-dien-5-yne

(I) (II)

(III)(IV) (V)

(I) Lowest set of locants for enes(1,4) gives the correct direction of numbering. The reversedirection would have given the set 2,5. Note that the letter a is suffixed to hex to makeit hexa which is used before diene.

(II) Lowest set of locants of enes (4,6) gives the correct direction. The letter a has beensuffixed to dec(deca).

(III) The lowest set of locants for enes and ynes are jointly found out because both ene andyne enjoy same priority. Here, yne gets lowest locant than ene. But while placing themin order, ene comes before yne. Note that the last letter e of ene has been deleted asit faces a vowel y. The root has not been suffixed with the letter a( not hepta) as it isnot facing di, tri, tetra etc. which begin with a consonant.

(IV) In this case, set of ene and yne locants are same on either side(1,3). In this case enegets precedence and the locant of ene should be lowest. Here also the last letter e ofene has been deleted.

(V) Here also the sets of locants are same on either side. So ene gets precedence. The roothex has been prefixed with the letter a(hexa) as it is facing diene. The last letter e ofdiene has been deleted as it is facing the vowel y.

More examples:

2

3

4

56

74

32

1

1'

2'

3'

4'

5' 5

2-(2-ethyl-3-methylpentyl)-3-methylpenta-1,3-diene

1

4-vinylhept-5-en-1-yne

In the first case the principal chain for naming is C-5 as it contains both the doublebonds. The other direction after C-2 would have given the longest chain(C-7), but accordingto old rule that is not the principal chain. Instead that part became a branched substituent(i.e a complex branch) and has been named as per rule.

In the second case the longest chain(C-7) containes one ene and one yne. So, wehad to exclude one ene from the main chain and is used as a substituent(vinyl).

��

12

34

56

7

1'2'

3'

4-(prop-1-enyl)hepta-1,4-dien

CH21

2

3

4

5

CH26

CH

CH3

CH3

CH3

3-ethynyl-4-neopentylhexa-1,5-diene

In the first case, there were two directions of getting the longest chain of C-7. Butwe chose the one as the correct longest chain which gives the lowest set of ene/ynelocants(1,4). The other direction would have given the set 1,5. Thus, the side chain attachedto C-4 becomes the alkenyl branch(prop-1-enyl).

In the second case, diene and enyne compete for the longest chain. In such case,according to rule(rule 12), ene is to be included in the main chain and yne to be excluded.So the parent compound is hexa-1,5-diene and there is ethynyl substituent at C-3. Note thatneopentyl can also be written as 2,2-dimethylpropyl. But neopentyl is the preferred name ofthe branch.

USE OF BIVALENT ALKYLIDENE GROUPS :

CH21

2 3

4 5

6 7

8 9 CH10

CH3

CH2

CH37

6

CH3

5

4

3

2

CH21

CH2

CH3

CH3

5-ethylidene-7-vinyldec-1-en-9-yne 3-sec-butyl-6-methyl-4-methylenehepta-1,5-diene

In the both cases, the longest chains containing maximum number of enes and ynesdo not contain the other C=C bearing group which is attached as a bivalent alkylidene groupor monovalent alkenyl or alkynyl group to the main chain.

SAQ.III.3: Write the IUPAC names of the following compounds.

(i)

CH3

CH3

CH3

CH

CH3

CH3

(ii) CH2

CH2

CH2

CH3

CH


(iii) CH2

CH

CH3

CH2CH3

CH3

(iv)

CH3 CH3

CH3

CH3

CH2

CH3

(v)CH3

CH3

CH3

CH3

CH2

NEW IUPAC RULES FOR NAMING POLYENES, POLYYNES AND ENYNES:

Like naming simple alkenes, alkynes and other functional compounds containing enesand ynes, the naming of polyenes/polyynes/enynes is done in similar manner according to theprovisional recommendations of IUPAC made in Janurary 2002.

1. The longest continuous carbon chain is found out irrespective of whether itaccommodates maximum number of multiple bonds or not. It may accommodate theminimum number of multiple bonds or even no multiple bonds in it if situtaion soarises. The branches containing C-C multiple bonds are named as alkenyl, alkynyl,alkylidene, alkenylidene, alkynylidene or the like.

2. Lowest set of locants rule is followed as usual for choosing the direction of numberingwithout giving any weightage to the branches containing the multiple bonds. Butmultiple bonds contained in the longest chain are given weightage as usual.

Examples:

CH37

6

5 4

CH

CH2

3

2 CH31

CH3

CH2

4

5

6

7

8

CH39

3

2

CH31

CH

4-ethynyl-2-methyl-4-vinylheptane(new name) 5-(prop-2-ynylidene)-4-vinylnona-2,7-diene(new)3-isobutyl-3-propylpent-1-en-4-yne(old name) 4-(but-2-enyl)-5-vinylocta-3,6-dien-1-yne(old)

In the first example, according to new rules, the longest chain does not contain anyof the multiple bonds. It is an alkane with vinyl and ethynyl as branches. According to oldrules both ene and yne are included in the principal chain of C-5 with propyl and isobutylas the branches. In the second example, according to new rules, the longest chain of C-9contains only two C=C bonds. Hence vinyl and prop-2-ynylidene are the branches of nonadiene.According to old rules, the longest chain is taken to be C-8 which contains maximum numberof multiple bonds(two double bonds and one triple bond) and more number of branches.

��

12

34

56

78

9

10

111'

2'

3' 4'

6-(2-methylbuta-1,3-dien-1-yl)undeca-2,4-dien-7-yne

In the above example, the chain containing four C=C would have been C-10, but thathas not been taken as the principal chain. Rather longest chain of C-11 containing threemultiple bonds(two double bonds and one triple bond) is taken as the principal chain.2-methylbuta-1,3-dien-1-yl group can be written as 2-methylbuta-1,3-dienyl by deleting 1 asthe locant of yl. Its name according to old rule is 5-(but-1-ynyl)-3-methyldeca-1,3,6,8-tetraene.

3. If two chains of same length compete for longest chain out of which one chainincludes one or more number of multiple bonds and the other excludes them orcontains less number of multiple bonds then the chain containing more number ofmultiple bond is taken as the correct longest chain even if that chain bears lessnumber of branches(violates branching rule). This is same as per the old rule.

CH37

6

5

4

3

2

CH21

CH3

CH3

CH3

(3-tert-butylhepta-1,5-diene)

In this case the longest chain of C-7 is available in two directions- one excluding oneC=C and the other including it. According to rule the one contanining C=C bond is taken ascorrect longest chain even if that is connected with less number of branches.

CAUTION: The students should name compounds according to new rules only whenrequired as these rules have not yet been published officially although they have beenrecommended by IUPAC since 2002. They should be familiar with both the systems.

COMPOUNDS CONTAINING TWO OR MORE IDENTICAL FUNCTIONALGROUPS:

1. POLYOL:

* Molecules containing more than one OH groups are called polyols eg. diol, triol,tetraol etc. Their IUPAC names are alkanediol, alkanetriol and so on. The letter e ofalkane is not to be deleted as it is facing a consonat in di, tri, tetra etc. The polyolis to be prefixed with its locants. Lowest set of locants for the ol functions decidesthe correct direction of numbering the longest chain. If this set tallies on two directions,then lowest set of locants for the branches decides the correct direction.

* The longest carbon chain holding maximum number of OH groups should be takenas the principal chain. For that purpose, the chain may not be the actual longestcontinuous carbon chain. If two chains having same length contain same maximum


number of OH groups then first lowest set of locants for ol functions is consideredwhich is followed by branching rule and finally the lowest set of locants for thebranches for choosing the direction of numbering.

(glycerol)(ethylene glycol)

propane-1,2,3-trio

CH2 CH CH2

OH OHOH

5-bromohexane-2,4-diol

65

43

21

ethane-1,2-diol

CH2 CH2

OH OH

OH OH

Br

OH

OH1

23

4

2-butylbutane-1,4-dio

In the first three examples, the longest chain holds all the OH groups. But in thefourth example, the chain holding both the OH groups is C-4 and it is taken as the principalchain for naming the parent compound. The names given inside parentheses are the commonor trivial names of the compounds which are accepted as systematic alternative names forthem by IUPAC.

CH36

5

4

3 CH3

2

1

OH

OHOH

3-(1-hydroxyethyl)hexane-1,4-diol

In the above example, the longest chain holds a maximum of two OH groups, so otherOH group remains in the branch called 1-hydroxyethyl. The longest chain(C-6) is availablein two directions. Both the chains also contain same number of branches(3). Hence, lowestset of locants for the ol functions(1,4) as against (2,4) decided the correct name.

POLYAMINES :

Compounds containing more than one amino groups are called polyamines. It can beprimary amino group(-NH

2), sec-amino group(-NHR) or tert-amino group(-NRR’). The rules

for naming such compounds are same as for polyols discussed before. See these examples.

CH31

2

3

4

5

6

7

CH38

NH2 CH3NH2

CH3

NH

1

2

3

CH3

NH

CH3

CH34

7-methyloctane-3,5-diamine N,N’,2-trimethylbutane-1,3-diamine

��

In the first example, both are primary amino groups while in the second example bothare sec- amino groups. That is why N,N’ locants were used in the second example. Lowestset of locants for amines has been considered in both the examples to choose the directionof numbering.

POLYONES

* Compound containing two or more keto functions is called a polyone eg. dione, trioneetc. The IUPAC name of such a compound is alkanepolyone eg. alkanedione,alkanetrione etc. with the locants of one preceding polyone(eg hexane-2,4-dione).The last letter e of alkane is not deleted because it is facing a cosonant in dione,trione etc. The lowest set of locants for the one functions holds good for decidingthe direction of numbering.

* The longest carbon chain containing maximum number of keto functions is taken asthe principal chain for naming the parent. Other keto function if any remains in theside chain(eg. 2-oxoethyl, 2-oxopropyl etc.)

CH3

5

CH36

4

3

2CH31

OO

CH3

CH31 2

34

5 CH3

OO

67

89

CH310

O

3-ethyl-5-methylhexane-2,4-dione 5-(1-oxoethyl)decane-2,7-dione or 5-acetyldecane-2,7-dione

In the first example, the longest chain of C-6 contains two C=O functions, sohexanedione is the parent compound. In the second example, the longest chain of C-10contains two C=O function. The other C=O remains outside the longest chain and is used asa substituent named as 1-oxoethyl(acetyl). The branch 1-oxoethyl is more popularly calledacetyl and has been accepted by IUPAC.

DIALS

Aldedyde(al) function appears at the terminal postions. Hence, there can be twoaldehyde groups in the longest chain. Only dial is possible and not beyound that. More CHOfunctions can remain outside the longest chain as branches. The IUPAC name of dial isalkanedial. The locants of al functions are usually deleted as they always appear at theterminal positions. The lowest set of locants for the other substituents linked with the chainis considered for naming. Note that the carbon atoms of both the aldehyde groups alwaysremain included in the main carbon chain.

H C

O

C

O

Hethanedial

(oxalaldehyde)

H C

O

CH2 C

O

Hpropanedial

(malonaldehyde)

H C

O

CH2 CH2 C

O

Hbutanedial

(succinaldehyde)


The names given inside parentheses, although trivial in their origin are more preferredas the systematic names by IUPAC.

H H

OO

123

45

2-methylpentanedial

Note that locants of al(two terminal carbon atoms in each case) are not used beforethe term dial. The lowest set of locants for the substituents has been considered whilechoosing the direction of numbering.

DICARBOXYLIC ACID:

If a molecule contains two COOH groups, it is a dicarboxylic acid and it is namedas alkanedioic acid. Since oic acids occupy the terminal positions, their locants are not usedin the name. Both the carboxyl carbon atoms are included in the main chain.

C C

O O

HO OHethanedioic acid

(oxalic acid)

HOOCCH2

COOH

propanedioic acid(malonic acid)

HOOC

CH2 CH2

COOH

butanedioic acid(succinic acid)

HOOC(CH2)3COOH

HOOC(CH2)4COOH

(pentanedioic acid/glutaric acid)

(hexanedioic acid/adipic acid)

5

43

2

1COOH COOH

2-ethyl-4-isopropylpentanedioic acid

In the last example, the branch ethyl gets precedence over isopropyl for the former’salphabetical seniority.

The names given inside parentheses, though trivial in origin are preferred names byIUPAC.

DIESTER, DIAMIDE, DI(ACID CHLORIDE) AND DINITRILE:

All the other derivatives of carboxylic acids containing two identical functional groupsare named as follows:

diester: dialkyl alkanedioate diamide: alkanediamide

di(acid chloride): alkanedioyl dichloride dintirile: alkanedinitrile

In all these cases the carbon atoms of the two functional groups are included in themain chain.

��

Examples

5 213

4

OO

OO

diisopropyl 2-methylpentanedioate

OH2N

NH2O

1

23

4

5

6

2-ethyl-5-methylhexanediamide

O

O

O

CH3 CH3

O

CH3

CH3

1-ethyl 5-isopropyl 2-methylpentanedioate

21 3

4

5Cl

O

Cl

O

3-ethyl-2-methylpentanedioyl dichloride

NC

CN12

34

5

6

2,4-dimethylhexanedinitrile

In the 3rd example, the diester contains two different alkoxy alkyl functions(-OR’). In sucha case the two alkyl groups(-OR’) are first arranged according to alphabetical order with thelocants of the carboxyl carbon prefixed before them.

COMPOUNDS CONTAINING THREE OR MORE IDENTICAL FUNCTIONALGROUPS SUCH AS AL(ALDEHYDE), OIC ACID, OATE, OYL CHORIDE, AMIDE,AND NITRILE:

Case-I: Longest chain bearing all functional groups:The continuous carbon chain can include the carbon atoms of the two functional

groups of the types mentioned above. If the third functional group(s) is(are) directly attachedto the main chain; then the carbn atoms of all the functional groups including those presentin the continous chain are excluded for determining principal chain for naming the parentcompound. The functional groups are used as suffixes according to the format given below.The parent compound becomes an alkane. The lowest set of locant rule for the functionalgroups and then for the substituents hold good in choosing the direction of numbering. Thelocants of the functional groups appear before the suffixes such as tricarboxylic acid,tricarboxylate etc.

alkane tricarboxylic acid(acid); trialkyl alkanetricarboxylate(ester);alkane tricarbaldehyde(aldehyde); alkanetricarbonitrile(nitrile);alkane tricarboxamide(amide); tricarbonyl trichloride(acid chloride)


5

213

4

OHO

O

OH

OOH

butane-1,1,2-tricarboxylic acid

O

OCH2CH3

O

CH3CH2O

OOCH2CH3

12

3

4

triethyl pentane-1,2,3-tricarboxylate

O 3

2

1

O

H

H

O H

propane-1,2,3-tricarbaldehyde

CH32

3

4

5

CH36

CN1

CN

CN

2-methylhexane-1,3,4-tricarbonitrile

1

O

Cl

O

Cl

O Cl

methanetricarbonyl trichloride

In the last example the set of locants 1,1,1 has been deleted since the parent alkaneis methane.

Case-II: Compound containing more than two identical functional groups out ofwhich two are included in the longest chain and other ones are not directly attachedto the main carbon chain:Look at the following example.

HOOCCOOH

COOH

1

2

3

4

5

6

7

4-carboxymethylheptanedioic acid

CN CN

CN

12

34

5

3-cyanomethyl-2-methylpentanedinitrile

When the third identical functional group is not directly attached to the longest carbonchain containing two other identical functional groups in the terminal positions, the naming isdone in the usual way, not like the previous case. In this case two functional groups areincluded in the longest chain to find the parent compound and the third which is not directlyattached to the longest chain is excluded from it. The group containing the third functionalgroup becomes a substituted alkyl group such as carboxymethyl, (2-carboxyethyl), cyanomethyl,(2-oxoethyl), (2-alkoxy-2-oxoethyl) etc. See some more examples

CH3CH2O OC

diethyl 3-methyl-5-(3-ethoxy-3-oxopropyl)octanedioate

3'

2'1'

1

23

45

6

78

COOCH2CH3

COOCH2CH32'

1'

2-methyl-3-(2-oxoethyl)hexanedial

1

23

4

56OHCCHO

CHO

Note the group (2-oxoethyl) can be named as formylmethyl in the first exampleabove and the group(3-ethoxy-3-oxopropyl) could be named as (2-ethoxycarbonylethyl) inthe second example above, but these latter ones are not the preferred names. Usually the

��

prefix formyl for aldehyde, alkoxycarbonyl for ester, halocarbonyl for acid halide, aminocarbonylfor amide groups are used only when the main carbon chain bears only the above mentionedgroups as substituents(not as substituted alkyl groups as given in the above examples) and thelongest chain includes another higher priority group than these.

SAQ III.4: Write the IUPAC names of the following.

(i)

H2N NH2

OO

O

NH2 (ii)

O

NH2

O

H

O

HO

(iii) O O

OOCH3

NH2NH2

(iv) O O

ONH2

NH2NH2

(v) O O

O

NH 2

OH

(vi) O

O

O

OO CH3

OHCl

(vii)OH

OH

OH

(viii)

O O O

CH3

CH3

CH3

(ix) NH

NH

CH3

CH3

(x)CH3

CHO

CHO

CHO

(xi)

O

C l

O

C l

O

C l

(xii) O

O O

O

CH3

CH3CH3

CH3

SAQ.III.5: Draw the structures of the following.

(i) ethyl 6-cyano-4-methyl-3-methylenehepta-4,6-dienoate(ii) methanetricarbaldehyde(iii) 2,3,4,5,6-pentahydroxyhexanal


(iv) 2,3,6-trimethyl-3-vinylocta-1,6-dien-4-yne(v) 3-(2-amino-2-oxoethyl)pentanediamide

PARENTHESIS METHOD OF WRITING STRUCTURAL FORMULA

The structures of organic molecules can be condensed by using the parenthesesformat. See these examples.

(CH 3)2CHC(CH 3)2COOH

H 3C

CH

H 3C

C

CH 3

CH 3

COOH COOH

p aren th esis fo rm u la c o nd e n sed stru c tu ra l fo rm u la

lin e stru c tu re

The two methyl groups put inside the first parenthesis are attached to the carbonatom shown adjacent to the first parenthesis. Similarly, the other two CH

3 groups put inside

the second parenthesis are directly attached to the carbon atom shown adjacent to the secondparenthesis. So, before naming the compound change the parenthesis formula to either linestructure or the condensed structural formula. Then name as usual. The name of the abovecompound is 2,2,3-trimethylbutanoic acid. See one more example.

C

H3C

H3C

CH 3

CH

CH 3

C

O

C

CH 3

CH 3

CH 2 CH 2 CH CH CO O CH

CH 3

CH 2 CH 3

(CH3)3 CCH(CH3)COC(C H3)2(CH2)2CHCHCOOCH(CH3)CH2CH3

sec-butyl 6,6,8,9,9-pentamethyl-7-oxodec-2-enoate

Three CH3 groups in the first parenthesis are attached to the carbon atom placed

adjacent to it. The subsequent CH3 group is attached to the carbon atom adjacent to it. Next

CO is a C=O. The subsequent two CH3 groups are also attached to the carbon atom adjacent

to them. (CH2)

2 means CH

2 groups are repeated two times in the main chain. Note that

(CH2)

n means CH

2 groups are repeated n times in the main carbon chain. This is because

CH2 group cannot remain outside the main chain as it is divalent (-CH

2-). The next CHCH

is CH=CH double bond. Simiarly in the alkyl group of ester function the CH3 in the parenthesis

is attached to to carbon adjacent to it. Note that you have to check the valency of carbonat every carbon and then decide whether it is C=C or C-C, C=O or C-O. The name of thecompound is sec-butyl 6,6,8,9,9-pentamethyl-7-oxodec-2-enoate.

SAQ III.6: Write the IUPAC names of the following from their condensed structures.

(i) (CH3)2CHCH(OH)CH(CHO)C(CH3)2CONH2 (ii) (CH3)3CNHCH(CH3)CH2CH3

(iii) CH3CH(CH3)OC(CH3)3 (iv) OHCCH(CH3)(CH2)3COC(CH3)2CCCH(CH3)2

��

NOMENCLATURE OF CYCLIC COMPOUNDS

1. The carbon atom of the ring attached to the highest priority group is numbered 1. Ifthere is a C=C double bond in the ring, then ene should get the lower locant. In theabsence of a C=C, lower locant or lower set of locants rule is applicable to choose thedirection of numbering in the ring.

2

3

1

4

6

5

OH

cyclohex-2-en-1-ol

2

3

1

4

6

5

OOH

CH3

6-methylcyclohex-2-ene-1-carboxylic acid

2

3

1

4

6

5

O

CH3

OH

4-hydroxy-2-methylcyclohexanone

In the 1st case the carbon atom of the cyclohexane ring attached to OH group isnumbered 1. The numbering direction is chosen in the manner so as to assign lowest locantto the ene. Same considerations have been given in the second example. Note that COOHgroup or in fact any other carbon bearing group like -CHO, -CONH

2, -CN etc. attached

to the ring are not included in the longest carbon chain. Therefore, they are suffixed ascarboxylic acid,(-COOH) carbaldehyde(-CHO), carboxamide(-CONH

2), carbonitrile(-CN) and

so on, in the manner done before in open chain(aliphatic) compounds. In the 3rd example,the locant of one has been deleted(cyclohexanone). When there is one suffix, the locant 1is not used but when there are two or more suffices, the locant 1 is used.

6

5

1

4

2

3

OCH3

H

2-ethylcyclohexanecarbaldehyde

2

3

1

4

6

5

O

ONH2

5-oxocyclohex-2-ene-1-carboxamide

2

3

1

4

6

5

N

O

H

5-formylcyclohex-2-ene-1-carbonitrile

2

3

1

4

6

5

OCl

OH

6-hydroxycyclohex-3-ene-1-carbonyl chloride


In all the structures containing C=C, the ene has been given the lowest locantirrespective of the position of the other functional groups like OH, CHO, CO etc. attchedto the ring. In the last example, the name could have been 2-hydroxycyclohex-4-ene-1-carbonyl chloride if OH group would have received the lowest locant. But this is wrong inthe naming of ring compuonds. If C=C is present, priority would be given to that. If thereis no C=C, then lowest set of locant rule comes into force. Look at these examples.

6

5

1

4

2

3

OO

OH

CH3

O

methyl 2-hydroxy-5-oxocyclohexanecarboxylate

3

4

2

5

1

6

OH NH2

3-aminocyclohexanol

3

2

1

CH3

CH3 CH3

1-isopropyl-3-methylcyclohexane

In the first example, C-1 is assigned to the carbon bearing ester group. Lowest setof locants assigns C-2 to OH group. In the second example, the carbon bearing OH groupgets C-1 as it is senior to NH

2 group. In the third example, both the branches are alkyl and

the set of locants are same on either direction. So alphabetical priority is considered to givelowest locant to isopropyl(C-1).

NAMING COMPOUNDS CONTAINING BOTH CYCLIC(ALICYCLIC) ANDACYCLIC(ALIPHATIC OR OPEN CHAIN) PARTS:

RULES :

1. If the principal functional group is attached to the aliphatic part, then the parentbecomes aliphatic compound. This remains valid even if the cyclic part contains moreno of carbon atoms.

2. If the principal group occurs in two or more carbon chains that are not attacheddirectly to one another but are separated by, for instance, a ring or hetero atom(eg.N, O, S etc), then that chain is chosen as parent for nomenclature which carries thelargest number of the principal groups. If the numbers of these groups in two or morechains are the same, then greater number of carbon atoms in a chain is considered.If that tallies then lowest set of locants is taken into consideration.

CH2CH2CH2HO

OH

OHCH2CH

1-[4-(3-hydroxypropyl)cyclohexyl]ethane-1,2-diol

3' 2'

1'4'3'' 2'' 1'' 12

3-cyclohexylbutanoic acid

12

34

CO O H

��

In the first case, -COOH group is attached to the aliphatic(open chain) part. Therefore theparent compound is butanoic acid.

In the second case, there are two aliphatic portions in between the ring structure. Theone containing 2 OH groups was considered for parent name(ethane-1,2-diol). The sustituentat C-1 of the parent compound is named following the rules for naming a complex branch.The main branch cyclohexyl is substituted at the 4 position by 3-hydroxypropyl group. Notethat there are three numbering systems i.e one for the parent chain, the other for the mainbranch(cyclohexyl) and the third for the sub-branch of the main branch.

3. If the principal group occurs only in the cyclic ring, then that ring forms the parentfor nomenclature.

4. If the functional groups occur both in aliphatic chain and in cyclic ring, the parentfor nomenclature is that portion in which the highest priority group occurs in largernumbers. In otherwords, the part containing highest priority functional group gives thename of the parent compound irrespective of number of other functional groups oflower priority occurs in the other part. If the highest priority groups are the samein the two portions then the cyclic ring is considered for naming the parent compound.

OH

2

1

2-ethylcyclohexanol(2-ethylcyclohexan-1-ol) 1-(3-hydroxycyclohexyl)ethane-1,2-diol

3'

1 '

2 '

1 2

CH CH2 OH

OHHO

NH2

O

O NH2

2-(8-amino-8-oxooctyl)cyclohexanecarboxamide

CH3

OH

NH2

NH2

1-(2,4-diaminocyclohexyl)propan-1-ol

In the first case the functional group -OH is present in the cyclic ring, so the parentis cyclohexanol. Note that the parent cyclohexanol could have been cyclohexan-1-ol. Sincenumbering of the ring has started from the carbon which bears OH group, the locant of olmust be 1. In such case, the locant 1 is usually dropped in cyclic systems.

In the second case, more number of -OH groups are present in the aliphaticpart, so the parent is ethane-1,2-diol, not cyclohexanol.

In the third case, the both the ring and aliphatic portions contain the same group(amide),then the ring is considered for naming the parent compound although the aliphatic part hasgreater number of carbon atoms.

In the fourth case the highest priority functional group is present in the aliphatic part,so the parent becomes aliphatic even though there are greater number of functional groupsof lower priority in the cyclic part.


More examples:

CH2

O

O

C CH2 CH3

O5

432

1

4-(2-oxobutyl)cyclopentane-1,2-dione

OHC CH2 (CH2)7 CHO

4-(9-oxononyl)cyclohexanecarbaldehy

4,5-dichloro-2[4-chloro-1-(hydroxymethyl)-5-oxohexyl]cyclohexanecarboxylic acid

1

23

4

5

6Cl

Cl

CO OH

OHO

Cl 3

2

1

4

5

6

OH

OH

COOH

(2,3-dihydroxycyclohexyl)acetic acid

In the first example there are two keto functions in the cyclic part, so cyclic partbecame the parent compound. In the second example, both the parts contain the samealdehyde(CHO) group, hence the cyclic part is taken for naming the parent even though theacyclic part contains more number of carbon atoms. In the third example, the cyclic partcontains the highest priority group among the two parts. So cyclic part became the parentcompound. The locant of carboxylic acid(1) has been dropped. In the fourth example, thehighest priority group is present in the acyclic part hence the parent became acetic acid. Thelocant of (2,3-dihydroxycyclohexyl) is 2 which has been dropped because there is only oneposition(2) in acetic acid for bearing a substituent.


(i)

CH3

OH

(ii)

ONH2

O

OH (iii)

CH3

O

O

OH

(iv)

CH3

OH

(v)

OHCH 3

CH3

CH 3

(vi)

CH3

COOH

OH

(vii)

CH3

CH3

CH3

NH2

(viii)

CH3

CH3

��

NOMENCLATURE OF AROMATIC COMPOUNDS:

Benzene and related compounds are called aromatic compounds.

CC

CC

C

C

H

H

H

H

H

H

(BENZENE)

Benzene is a six membered ring containing alternate C-C single bonds and C=Cdouble bonds. Each carbon is attached with one H atom. In the line structure(middle) the Cand H atoms are not shown. Benzene can also be shown by a graphic formula(last structure)in which a circle is drawn inside a hexagon. This is called the resonance hybrid structureof benzene. Benzene and aromatic compounds are cyclic compounds like alicyclic compoundssuch as cyclohexane, cyclopentane etc. but they exhibit completely different properties.

Monosubstituted Benzene:

* All the six H atoms in benzene are equivalent. If any one H atom is replaced by anyother group, we call it a monosubstituted benzene. The IUPAC names of somecommon monosubstitued benzenes are given below.

CH3Cl OH NO2

toluene(methylbenzene)

chlorobenzene phenol nitrobenzene

NH2

aniline(hydroxybenzene) (aminobenzene)

1 2

CHO COOH COCH3

benzaldehyde benzoic acid acetophenone(1-phenylethanon

CN COCl CONH2 COONa

benzonitrile benzoyl chloride benzamide sodium benzoate methylbenzonate

COOCH3

OCH3 O

methoxybenzene(anisole)

benzophenone(diphenylmethanone)

The names given within parentheses are the alternative names which are less preferred.Note that the substituent can be attached to any carbon atom of the ring as all the 6 carbonatoms are equivalent. Conventionally, we attach a group at the uppermost or upper rightpositions.


* If the substituent contains one or more carbon atoms which bears the functionalgroup or in otherwords the functional group is not directly attached to the benzenering, then it is named as phenyl substituted aliphatic compound. Note that if a caronbearing functional group like -CHO, -COOH, -COOR, -CONH

2, -CN etc is directly

attached to the ring then the compound gets an aromatic namen as given before.

OH

phenylmethanol

COOH

phenylacetic acid

OH

triphenylmethanol

SAQ III.8: Write the IUPAC names of the following compounds.

CH2CH3 CHH3C CH3

COCH2CH3

I

OCHCH3 COOCH(CH3)2

(i) (ii) (iii) (iv) (v) (vi)

(vii)


(i)Cl

(ii)NH2

(iii) O

O

CH3

(iv)CN

(v)

CH3

CH3

CH3

CHO

DISUBSTITUTED BENZENE

When two substituents are attached to the benzene ring at two different carbon atoms therecan be three position isomers.

X

Y

X

Y

X

Y

12

11

2 2

3 3

43

4

5 55

6 6 6

4

1,2- or ortho 1,3- or meta 1,4- or para

(i) 1,2- or ortho(o-)disubstituted benzene: When the two substituents are attached toany two adjacent carbon atoms, then it is called 1,2- or ortho or in short o- disubstitutedbenzene. When two groups are same(X), then you can assign C-1 to any of the twocarbon atoms of the ring to which substituents are attached, so that the other carbonatom will be C-2. But when the groups are different(X and Y), then C-1 is assigned tothat carbon of the ring which bears the higher priority functional group.

��

(ii) 1,3- or meta(m-)disubstituted benzene: When the two substituents are attached to1st and 3rd carbon atoms, it is called 1,3- or meta or m- disubstituted benzene. Note that,like o-disubstituted compound, you can assign C-1 to any carbon atom if the twosubstituents are same(X). But, if they are different(X and Y), then C-1 is assigned tothat carbon which bears the higher priority functional group.

(iii) 1,4- or para(p-)disubstituted benzene: When the two substituents are attached to 1stand 4th carbon atoms, it is called 1,4- or para or p-disubstituted benzene. Note that, likeo- and m-disubstituted compounds you can assign C-1 to any carbon atom if the twosubstituents are same(X). But if they are different(X and Y), then C-1 is assigned tothat carbon which bears the higher priority functional group.

Note that, when X and Y are different the parent of the aromatic compound is determinedaccording to the higher priority group.

PRIORITY ORDER AMONG FUNCTIONAL GROUPS:

The priority order among the functional groups(type C) upto -NH2 group is same as

given for aliphatic compounds before.

-COOH >-SO3H > -COOR’ > COCl > CONH

2 > -CN > -CHO > -COR > -OH > -NH

2

Note that like for the aliphatic compounds there is no relative priority among groupslike -OR(alkoxy), -R(alkyl), -X(halo), -NO

2(nitro), alkenyl and alkynyl which belong to the

type-A category. When there are two groups from this category then C-1 is assigned tothat carbon atom of benzene ring which bears the alphabetically senior group.See the following examples.

COOH

HO

salicylic acid(2-hydroxybenzoicacid/ o-hydroxybenzoicacid)

CN

OHC

12

3

4

3

21

4-formylbenzonitrile(p-formylbenzonitrile)(not 4-cyanobenzaldehyde)

NH2

HO1

2

3-aminophenol(m-aminophenol)(not 3-hydroxyanilin

CH3

1-methyl-3-vinylbenzene(3-vinyltoluene)

CH3

Cl1-chloro-3-methy l benzen

CH2CH3

OCH3

1-ethy l-4-methoxybenzen

The prefix o-(for ortho), m-(for meta) and p-(for para) can be used in place oflocants 2, 3 and 4- respectivly with respect to C-1. In the first case the higher priority groupis -COOH, so the carbon atom of benzene ring attached to -COOH group has been numbered1. Then direction of numbering is chosen according the lower set of locants rule. Its commonname(salicylic acid) is the preferred IUPAC name. In the 2nd and 3rd examples, -CN and


-OH groups have higher priorites over -CHO and -NH2 groups respectively(refer priority

order given before). In the 4th, 5th and 6th examples, the branches do not have any relativepriority among them and so the alphabetically senior group has been numbered C-1.

* When two groups are identical, the multiplying prefix di- is used with the name ofthe substituent eg. 1,2-dinitrobenzene, 1,3-dihydroxybenzene etc. Carbon bearingfunctional groups eg. -COOH, -CHO, -CN etc. are to be expressed as suffixes like1,2-dicarboxylic acid, 1,3-dicarbaldehyde, 1,4-dicarbonitrile of the parent benzene andnot as derivatives of benzoic acid, benzaldehyde and benzonitrile respectively. Thecommon names of some compounds have been accepted as preferred IUPAC names.The beginnners are advised to familiarise both the systematic and preferred names.

OH

OH

OH

OH

OH

OH

COOH

COOH

pyrocatechol(1,2-dihydroxybenzene/o-dihydroxybenzene)

resorcinol(1,3-dihy droxybenzene/o-dihy droxybenzene)

hydroquinone(quinol/1,4-dihy droxybenzene/p-dihy droxybenzene

phthalic acid(benzene-1,2-dicarboxy licacid)

COOH

COOH

COOH

COOH

CH3

CH3

CH3

CH3

isophthalic acid(benzene-1,3-dicarboxylic acid)

terephthalic acid(benzene-1,4-dicarboxylic acid)

o-xylene(1,2-dimethylbenzene/o-dimethylbenzene)

m-xylene(1,3-dimethylbenzene/m-dimethylbenzene)

CH3

CH3

NH2

NH2

NH2

NH2

NH2

NH2

p-xylene(1,4-dimethylbenzene/p-dimethylbenzene)

benzene-1,2-diamine(1,2-diaminobenzene/o-pheny lenediamine)

benzene-1,3-diamine(1,3-diaminobenzene/m-pheny lenediamine)

benzene-1,4-diamine(1,4-diaminobenzene/p-pheny lenediamine)

* If out of the two substituents, one contains one or more carbon atoms which beara higher priority functional group, it is named as a substituted aliphatic compound.However if the higher functional group is directly attached to the benzene ring, thenit is named as a substituted aromatic compound. If the aliphatic and aromatic partspossess identical functional group, then the compound is named as aromatic.Theseset of rules are same for any compound containing both acyclic and cyclic parts aswe had discussed before.

��

OH

CHO

(4-hydroxyphenyl)acetaldehyde

OH

CH3

CH3

CH3

4-(2,2-dimethylbutyl)phenol

HOOC

COOH

4-(carboxymethyl)benzoic acid

1

2

3

NH2

OH

(3-aminophenyl)methanol

2

1

OH

1

CH32

CH3

NH2

2-(1-amino-1-methylethyl)phenol

OH

phenylmethanol

SAQ III.10: Write any one IUPAC name of the following aromatic compounds.

OC H2CO OH

Cl

Cl

COCl

CONH2

NO2O2N

CH3

NH2

Cl

O2N

COOH

SO3H

CH2CH3

Cl

NO2

NO2

Cl Cl CH(CH3)2

NO2

CN

COCH3

Br

I

CHO

CHO

CONH2

H2NOC

COOC2H5

CN

C2H5

CH3

SAQ III.11: Write the preferred IUPAC names of the following compounds.

(i) CH3

CHO

N

CH3 CH3

(ii)

NH2

CH3

CH3

(iii)

CN

CH3

CHO

(iv)

CHO

COOH

CH3

(v)NO2

CH3

COOH


TRI- AND POLY- SUBSTITUTED BENZENE :

(i) When benzene ring is attached with more than 2 substituents, then the functionalgroup(type C) having the highest priority gets the lowest locant(1). The parent nameof the compound(eg. phenol, benzoic acid, aniline etc) is assigned accordingly. Thenumbering direction is chosen while keeping the lowest set of locants rule in mind.If all the substituents belong to type-A category having no relative priority then lowestset of locants is considered for naming the compound. Alphabetical seniority of thegroups is not considered for the purpose of assigning the lowest locant as wewere doing for disubstituted benzenes. See these examples.

OH

COOH

CH3

Br

BrBr

NO2

NO2O2N

NH2

BrBr

Br CHO

COCH3

NCCONH2

OHHO

5-hydroxy-2-methylbenzoic acid

1,2,3-tribromobenzene 1,3,5-trinitrobenzene

4-acetyl-2-formylbenzonitrile 2,6-dihydroxybenzamide

65

4

32

1

6

5

4

32

1

3

21

2,4,6-tribromoaniline

65

4

3

2

1

6

5

4

32

16

4

3

21

5

In the 2nd and 3rd examples the three groups are identical. So lowest set of locantsrule has been followed. In all other examples, there is one or more substituents belongingto type C. In such case, the carbon atom of benzene ring bearing the highest priority grouphas been numbered 1. Then the lowest set of locants is considered for choosing the directionof numbering.

O2N

CH3 Cl

4-chloro-2-methyl-1-nitrobenzene(correct)5-chloro-2-nitrotoluene(wrong)

O2N

H2N Cl

5-chloro-2-nitroaniline(correct)2-amino-4-chloro-1-nitrobenzene(wrong)

3

2

4

1

5

4

32 1

In the 1st example, -CH3, -NO

2 and -Cl have no relative priority as they belong to

type A category and hence lowest set of locants decides the correct name. But in the 2ndexample, -NH

2 group belongs to type C functional group and the other two belong to type

A. Hence, the locant of amine(parent compound is aniline) has been 1 and then lowest setof locants is considered for choosing the direction of numbering. In the example below onlylowest set of locants has been considered as all the branches belong to type A.

CH2CH3

OC H3

Cl

2-chloro-4-ethy l-1-methoxy benzene

1

2

34

(not 3-chloro-1-ethy l-4-methoxy benzen

��

SAQ III.12: Name the following compounds.

COOCH3

CH3

NO 2 CHOO2N

COCH3

O2N

CH3 C2H5 COOCH3

COOCH3

Br I

Cl

OC2H5

Cl

CH3

H3C

H3C

NO2

NH2O2N NO 2

NO 2

COCl

Cl

COOH

POLYNUCLEAR AROMATIC COMPOUNDS:

Compounds containing more than one benzene ring fused at the ortho or 1,2 positonsare called polynuclear or condensed aromatic compounds. A few examples are given below.

or

1

2

3

45

6

7

8

1

2

3

45

6

7

8

10

(napthalene)

or

1

23

45

6

7

8 9

98

7

6

5 4

32

110

(anthracene)

When two benzene rings are fused, it is called naphthalene. The IUPAC rules fornumbering the carbon atoms in the rings have been shown. The carbon atoms at the fusionpositions(ortho) are not counted while numbering. Similarly when three benzene rings arefused, it is called anthracene. The two pairs of carbon atoms present at the fusion pointsare not counted while numbering. After completing the numbering of one terminal ring(eitherclockwise or anticlockwise), the carbon atoms of the other terminal ring are numberedbypassing the middle ring. The middle ring is numbered at the last(9 and 10). The numberingin naphthalene and anthracene can also start from the left terminal ring in the same way asthe right terminal ring. Condensed aromatic compounds containing 4, 5 rings are calledtetracene and pentacene respectively. Condensed aromatic systems having greater numberof rings also exist but their discussion will not be made here.Examples:

OH

COOH

CHO

CH3

3

2

12

1

6

5 4

3

1

2-naphthol1-naphthoic acid 6-methyl-1-naphthaldehyde

NH2

H5C2

6-ethyl-2-naphthylamine

2

1

65 4


4

2

321

2

1

CN

CH3CH3

COOH SO3HNH2

1

6

5

3

5 4

7

8

1-methyl-2-naphthonitrile5-methylanthracene-1-carboxylic acid 8-aminonaphthalene-1-sulfonic acid

Note that lowest set of locant rule is not applicable in condensed system. Althoughthe highest priority group will get the lowest locant, the numbering procedure will remain thesame as shown before.

SAQ.III.13: Name the following compounds.

Cl

OH

CONH2

CH3

OH

CH3

Cl

ClCOOH

NH2HO

HETEROCYCLIC COMPOUNDS:Cyclic compounds containing atoms like O, N or S besides carbon atoms in the ring

are called heterocyclic compounds. A few simple heterocyclic compounds and their numberingsystems are given below with their line structures.

4 3

52

O1

4 3

52

NH1

4 3

52

S1

2

N1

3

6

5

4

furan pyrrole thiophene pyridine

NH

O

5

4

6

O1

2

3

O1

2

3

4

5

6

piperidine tetrahydrofuran(THF) 2H-pyran 4H-pyranAll the other positions than the O, N or S are occupied by carbon atoms which are

attached to required number of H atoms. In the last two examples, 2H and 4H signify thepresence of saturated carbon atom(sp3 hybridised) at the positions 2 and 4 respectively.Pyran contains one O atom, five carbon atoms and two C=C in a six membered ring. Thereare two isomeric pyrans(2H and 4H). More discussion on naming heterocyclic compoundswill not be made here.

��

NOMENCLATURE OF BICYCLIC COMPOUNDS:

The compounds in which two rings are fused with each other having one or moresides(C-C bonds) in common to both the rings are called bicyclic compounds. In thesecompounds the two rings share at least two carbon atoms. The number of shared carbonatoms can also be more than 2.

Bridgehead carbon atoms:

Any carbon atom which is connected with 3 or 4 other carbon atoms is called abridgehead carbon atom. In bicyclic compound bridgehead carbon atom is connected with3 other carbon atoms. There are two bridgehead carbon atoms in a bicyclic compound.

bridgehead carbon

bridgehead carbon

bridges

In the 1st example two 4-membered rings are fused at the 1,2 positions. In the 2ndexample, one 8 membered ring is fused with with another 6 membered ring at the 1,2,3positions. In the 3rd example, two 3-membered rings are fused at the 1,2 positions. Thebridgehead carbon atoms are shown in the diagramme by arrow marks. Each bridgeheadcarbon atom is connected with 3 other carbon atoms.

BRIDGES:

With respect to the bridgehead carbon atoms there are three bridges. The carbonchain connecting the bridgehead carbon atoms is called a bridge. There are threebridges in a bicyclic compounds which have been shown in the diagramme. Note that abridge can be merely a covalent bond connecting the bridgehead carbon atoms as you cansee in the 1st and 3rd examples given above. In such a bridge there is no carbon atom.

Definition of a bicyclic compound:

A bicyclic compound is one which can be converted to an open chain acycliccompound by making cleavage(scission or breakage) of covalent bonds two times. Thediagramme below shows how successive cleavages for two times converts a bicyclic compoundinto an open chain compound.

1st cleavage 2nd cleavage

open chain

NAMING BICYCLIC COMPOUNDS:(i) There is a main ring and a main bridge. The two longer bridges alongwith the

bridgehead carbon atoms constitute the main ring. The other bridge becomes themain bridge. In the above example the two terminal bridges are longer while theinternal bridge is the shortest consisting of a covalent bond only(no carbon atom).Hence the main ring contains six carbon atoms including the bridgeheads. The internalbridge which is excluded from the main ring becomes the main bridge.


(ii) The name of the compound contains three parts as shown belowbicyclo[x.y.z]alkane

The three numbers x, y and z separated by full stops are written in decreasing orderwithin square bracket. These numbers determine the size or the number of carbon atomspresent in the three bridges. The bridgehead carbon atoms are not included in these numbers.If a bridge does not contain any carbon atom( i.e when it is merely a covalent bond), thisnumber is taken to be 0.

(iii) All the carbon atoms including the bridgehead ones are considered for the name ofparent alkane.

bicyclo[2.2.0]hexane bicyclo[5.3.1]undecane

532 12

0

bicyclo[1.1.0]butane

1 10

Naming substituted bicyclic compounds:

(iv) The numbering of the bicyclic compound starts from one bridgehead carbon atom viathe longest bridge to the other bridgehead carbon atom. Then the numbering iscontinued around the main ring upto the last carbon atom which appears before the1st bridgehead. After that the numbering is continued with the carbon atoms of themain bridge(shortest bridge). Note that the carbon atom of the main bridge closer toC-1 gets the lowest number among all the carbon atoms of the main bridge. Notealso that the main bridge containing no carbon atom(only covalent bond) does not getany more number after the end of the main ring.

(v) The numbering starts from that bridgehead which gives lower locant to any functionalgroup, multiple bond or any substituent present in the longest bridge. If there is nobranch in that bridge then lower locant is received by a branch in the shorter andshortest bridges. The priority order remains the same as for other compounds expectingthe inclusion of carbon-carbon multiple bonds in this case.

-COOH >-SO3H > -COOR’ > COCl > CONH

2 > -CN > -CHO > -COR > -OH

> -NH2 > C C > C C

(Note that in aromatic compounds alkenyl and alkynyl groups are excluded from thebenzene ring while in bicyclic compounds C-C multiple bond can remain as a part of the ring.In such a case ene and yne have their precedence over all other type A groups)

Substituents are written before the prefix bicyclo. The suffix ane of alkane changesto ene or yne if there is double or triple bond. The suffix -ol, -one, -al, -oic acid etc. canbe used in place of ‘e’ of alkane if there is a functional group. The locants of the functionalgroups are to be used as usual like the nomenclature in aliphatic compounds. See theseexamples.

5 4

6 1

3

2

CH3

5-methylbicyclo[2.2.0]hex-2-ene

2 1

3

4

5 6

7

11

10

8

9

CH3

3-methylbicyclo[5.3.1]undec-8-ene

3

1

4 2CH3

4-methylbicyclo[1.1.0]but-1-ene

��

CH 3

23

4

5

6

78

9

1

10

6-m ethylb icyclo[5 .2 .1]dec-3-ene

OC H3

O2N

HO

2

1

4 5

6

7

8

3

9

4- methoxy-2-nitrobicyclo[3.2.2]nonan-6-olIn the 1st example, since two bridges are of same length(2 carbon atoms) the

direction of numbering which gives lowest locant to ene has been chosen. In the 2ndexample, the numbering starts from the bridge head which gives lower locant to ene(8). Hadwe started the numbering from the other bridge-head, the locant of ene would have beengreater(9). In the 3rd example, two bridges are of same length ( 1 carbon atom) so ene getspriority over methyl substituent. In the 4th example, ene gets the lower locant as it has higherpriority over methyl group. In the 5th example, the main ring contains the highest priority-OH group in the shorter bridge. Although numbering is first completed in the longest bridgeaccording to rule, it is done in such a direction(clockwise)that the -ol(alcohol) gets the lowerlocant(6). Numbering in anticlockwise direction whould have given the locant 7 to the -olfunction.

SAQ III.14:Write the names of the following bicyclics.

(i) (ii) (iii) CH3 (iv)

CH3

(v) (vi)

CH3

(vii)

NH 2

(viii) NH2

COOH (ix)

NH2

(x)

OHC

NOMENCLATURE OF SPIRO COMPOUNDSThe compounds in which two rings share one common carbon atom are called

spirocompounds.

The IUPAC name of such compounds is as follows.

spiro[x.y]alkane

x and y are chain lengths in the two rings or the number of carbon atoms in the two ringswhich link to the common atom(called spiro atom), which are separted by full stop. Notethat the spiro atom is excluded in these numbers. The numbers are written in increasing ordereg. [4.5] unlike that followed in bicyclic compounds(decreasing order). While naming theparent alkane the total number of carbon atoms in the compound is counted.


4

3

2

1

5

6 7

8

10 9

spiro[4.5]decane

Note that ring sizes are 4 and 5 on the two sides of the common or spiro atom whichare written in increasing order with full stop in between them.

(iii) Naming substituted spirocompounds: The numbering starts in the smaller sizering from the carbon atom adjacent to the spiro atom and proceeds around the smallerring back to spiro atom and then proceeds around the second ring(larger size ring).While going from the smaller ring towards the larger ring the lowest set of locantsrule is kept in mind. If there is a C=C, then ene should get the lower locant comparedto alkyl or other type A groups.

2

1

3

4 5

8 7

6

CH3

8-methylspiro[2.5]oct-4-ene

9

8

7

65

4

10

3

1

2

CH3

1-ethylspiro[3.6]dec-6-ene

8

7

9

6

5

4

1

3

2

spiro[4.4]nona-2,7-diene

SAQ III.15: Name the following spiro compounds.

(i)

CH3

CH3

(ii)- CH3

CH3

(iii)

CH3

(iv) Cl (v) CH3

ALTERNATIVE NAMING PROCEDURE FOR ETHERS AND 20 AMINES

Ethers:(OXA System)

1. Oxygen atom in ether is treated like a carbon atom in finding out the longest continuouschain including the oxygen atom. In otherwords, the oxygen atom is counted like acarbon atom in determining the the name of parent alkane. The ether group(oxygenatom) is indicated by the prefix oxa with its locant placed before it. Lowest set oflocants rule is followed while choosing the direction of numbering. Note that ethergroup (O atom) does not enjoy any priority as functional group.

��

CH36

5

O4

3

2

CH31

CH3

(2-methyl-4-oxahexane)

Note that IUPAC does not have a fixed procedure for naming ethers, although the onediscussed before(alkoxyalkane) is the preferred name. The oxaalkane procedure ofnaming ether is simpler, although used to a lesser degree of preference.

SAQ III.16: Write the names of the ethers as oxaalkanes. Also give their otherpreferred names as alkoxyalkanes.

(i)

CH3

O CH3

CH3

CH3

CH3

(ii) CH3

CH3

CH3

CH3

O

CH3

CH3

CH3

(iii) CH3

O

CH3

CH3

CH3

CH3

Cyclic ethers:When oxygen atom remains as a part of a ring, it is a cyclic ether. The systematic names

of these ethers and their alternative names according to oxa system are given below.

O

oxirane

O

oxetane

O

oxacyclopentane(tetrahydrofuran or THF)

O

O

1,4-dioxacyclohexane(1,4-dioxane)(oxacyclopropane) (oxacyclobutane)

Note that oxirane is also commonly called ethylene oxide or epoxyethane.

Sec-amines (AZA System)

Like oxygen atom in ether, the nitrogen atom in a sec-amino group( NH) is counted likea carbon atom in finding out the longest continuous chain. The prefix aza is used for the aminofunction with its locant before it.

CH35

4

NH3

2

1

O

OH

3-azapentanoic acid [ 2-(ethylamino)acetic acid/N-ethylglycine]

SAQ III.17: Draw the structure of the following compounds.Also give their preferred names.(i) 5-aza-3,4-dimethyloctan-2-one (ii) azacyclohexan


SUBSTITUTED OXIRANES(EPOXYALKANES), IMINES, LACTONES,LACTAMS, IMIDES, KETENES

1. Substituted oxirane: The O atom of oxirane is always numbered 1. Alphabetical seniorityof alkyl groups decides the correct direction of numbering. These are also named asepoxyalkanes, the locants of the epoxy are to be prefixed to it.

H 3C CH CH CH 2 CH 3

O

(2 ,3 -ep ox yp en tan e)

1

23

2 -e th yl-3 -m eth ylox iran e

2. Imines: =NH is called imine group. It is a bivalent group. The name of imine is alkan-x-imine where x is the locant of imine.

H 3C CH 2 CH 2 CH NH

butan -1 -im ine

H 3C CH 3

NHprop an-2-im in e

3. Lactones: Cyclic esters are called lactones. Butyrolactone, valerolactone, caprolactoneare a few examples of lactones.

H 2C

H 2C

H 2C C

O

OH 2C

CH 2

H 2C C

O

CH 2

O

H 2C

CH 2

H 2CC

O

CH 2

CH 2

O

-bu tyrolacton e -valerolactone -caprolactone

4. Lactams: Cyclic amides are called lactams. Butyrolactam, valerolactam, caprolactam arefew examples of lactams.

H 2C

H 2C

H 2C C

O

NHH 2C

CH 2

H 2C C

O

CH 2

NH

H 2C

CH 2

H 2CC

O

CH 2

CH 2

NH

-butyrolactam -valerolactam -caprolactam

5. Ketenes: R-CH=C=O are called ketenes. Such compounds are named according to IUPACrule.

Example: CH3-CH=C=O prop-1-en-1-one

6. Imides: Imides contain -CO-NH-CO- group. It is analogous to acid anhydride except-O-in anhydride is replaced by -NH- in imide. They are named according to IUPAC rules.

CH3-CO-NH-CO-CH

3N-acetylacetamide.

��

PRACTICE QUESTIONS

SET-I: Write the IUPAC names of the following compounds.

(a) CH3 CH C CH3

CH3

CH3OH(b)

H3C C C C

CH3

CH3

CH3 (c) ClCH2CH

CH3

CH

CH3

CH2CH3

(d) H3C CH

CH3

C CH CH3

CH3 (e) H3C CH

CO CH3

CHCH3

CH3

(f) H3C CHCH2

CH3

CH

CH3

C

O

O CH2 CH3

(g) H3C CH2 CH

CO H

C

CH3

CH3

CH3(h)

H3C C

CH3

CH3

C

O

Cl(i)

H3C C

CH3

CH2 C

O

NH2

CH

CH3

CH3

(j) H3C C

CH3

CH3

NH CH

CH3

CH3

SET-II: Write the IUPAC names of the following compounds.

(a) (CH3)2CHCH(CH3)C(CH3) CH2 (b) (CH3)3COH (c) (CH3)3CCH2NH2

(d) (CH3)3CC(CH3)2COOCH3 (e) CH3CH(CH3)C(CH3)2CHO (f) CH3CH(C2H5)COOCH(CH3)2

(g) (CH3)3C C

O

O C

O

C(CH3)3(h) (CH3)2CHOCH2CH3 (i) (CH3)2CHCH2C CC(CH3)3

(j) (CH3)3CCN

SET-III: Write the IUPAC names of the following.

(a) O

(b) (c) OH

(d)

H3CCH3C

H3C

C

O

O Ca

2


(e) N (f)

CO H

(g) CO

NH(h)

Br

(i) H

O

O CH3

(j) Br

O

(k) CH3SCH2CH3

(l) (CH3)2CHCH(SH)C(CH3)3 (m) (CH3)

3CCH

2NCS

SET-IV: Draw the structural formual of the following.

(a) 2,3-dimethylbutan-2-ol (b) 2,2-dimethylpentanal(c) 3-ethyl-2,3-dimethylpentanoic acid (d) N-ethyl-N,2-dimethylpropan-2-amine(e) 2-methylbutanoyl chloride (f) ethyl 2-methylpropanoate(g) 2-ethoxy-3-methylbutane (h) 3,3-dimethylpentan-2-one(i) 2-methylbut-2-ene (j) acetic 2-methylpropanoic anhydride

SET-V : Write the IUPAC names of the following compounds.

(a)

CH3 CH3

CH3

CH3

CH3

CH3

(b) CH3

CH3 CH3

CH3CH3

CH3 (c) (CH3)2CHCH2OH

(d) (CH3)3CCH2CHO (e)

CH3

CH3

OH

CH3

CH3

CH3

(f) CH3CHCHCH2OC(CH3)3

(g) (CH3)2CHCH2COOC(CH3)3 (h) CH3CH2CH(CH3)CH2CH(CH2CH3)CH2CH2CH3

(i)CH2 C CH(CH3)2

CH2CH3

SET-VI: Give the structure for the following.(a) cyclohexanecarbaldehyde (b) hexa-1,4-diyne(c) 5-methylhept-5-en-1-ol (d) cyclopent-2-en-1-amine(e) bicyclo [2.2.2]octane-2,5-dione (f) 2,3-dimethyloctanedioic acid(g) 4-tert-butyl-2-methyloctane (h) 3-methyl-6- (prop-1-enyl) cyclohex-1-ene(i) 5-(1,2-dimethylpropyl)undecane (j) propane-1,2,3-tricarboxamide(k) 7-methylbicyclo[4.1.0]hept-2-ene (l) 2-phenylethanol(m) 4,4-diemthylpentan-2-one (n) 1-isopropyl-2-methylpropyl thiocyanate

Set-VII : Write the IUPAC names for the following structural formulae.

(a)CH3 CH

CH3

CH

Cl

C

O

CH CH3

CH2 CH3(b)

CH

CH3

OH

O

Cl (c)CH3

OH

OH

NH2O

��

(d) (CH3)3C CH2 CH

CO2H

NH2(e) CO NHCH2CH3

Br (f)

CH3 CHO

CH3 OH

CH3

(g)

CH2 CHO

OHCH3

(h)

OH

CH3NH2

(i) CH3CH2NH CH2CH2 C CH2CH3

CH3

CHO

(j) CH3

COOH

CH3 CH3

CH3

(k)

O

CH3

Cl

(l)O

CH3

NH2

(m)CH2

CH3CH3

CH3

(n)CH3

CH3

OH

OH

OH

CH3

(o) (CH3)2CHCOCH2CH3

SET VIII : Draw structural formula for each of the following compounds.

(a) 1-cyclopentyl-2,2-dimethylpropan-1-one (b)Ethyl cyclobut-2-enecarboxylate(c) p-chlorobenzoic acid (d)sec-butyl 4-methylpent-3-enoate(e) 4-methoxybut-2-ynoic acid (f) N-methyl-N-phenylacetamide(g) 2,4,6-tribromononanenitrile (h)4-methylcyclohex-2-en-1-one(i) tetraisopropylammonium chloride (j) (allyloxy)methylbenzene(k) diethyl 6-(3-isopropoxy-3-oxopropyl)- (l) 4-methoxy-2-methylhex-1-ene 2-methylundecanedioate(m) (4-formyl-3-hydroxy-2-methylhex- (n) 4-ethoxy-2,3-dimethyl 3-enenitrile -5-oxopentanoic acid(o)

SET IX: Write the IUPAC names of the following structures.

(a) CH3CH2CHC

CH3

CCH3

(b) C6H5CH2OCH2CH(CH3)2

(c) OHC(CH2)3CO2H (d) CH2COCl

(e) (CH3)3CCH(CH3)CH2NHCH3 (f) CH2Cl

(g) CH3CH(CH3)CHCHCO2C(Cl)(CH3)CH2CH3 (h) (CH3)3CCH CCH2CH(CH3)CO2H

Br


(i)

CH CH2

NO2

(j)

CH3

(k) (CH3)2CHNHCH2CH(CH3)(CH2)2CO2CH2CH(CH3)2 (l) NCCONH2

(m)

O

OH

O

OH(n)

O

CH3

CH3

(o)

CH3

(p)CH3

NCCH3

CH3

SET-X: Draw the structural formula of the following compounds.

(a) 5,6-diethyl-2,3,7-trimethylnonan-3-ol (b) isobutyl 3-phenylbutanoate(c) 4-isopropyl-3-phenylcyclohexanone (d) 3-(1,2-dimethylpropyl)-4-ethylphenol(e) 3-nitroaniline (f) 2-isopropoxypropane(g) 7-methylspiro[2.4]hept-4-ene (h) N,3,3-trimethylpentanamide(i) 6-methylocta-1,3,5-triene (j) 5-(1-cyanoethylidene)-6-methyloct-3-ynoic acid(k) 4,4-diethylcyclohexa-2,5-dien-1-one (l) 3-bromo-4-cyclopropylcyclobutane-1,2-diol

SET-XI: Write the IUPAC names for the following compounds.

(a) (CH3)2C CHC(Cl) CHCH CHCO2H (b)

(CH3)3CCCH2CH2CH(CH3)2

OH

CH2CHCH2CH3

OH

(c) CH3C(CH

3)

2CH(C

6H

5)COCH

3(d) H

2NCH

2CH(OH)CH

2CH

2CH

2NH

2

(e)

C2H5

CO2C2H5

OCH3

(f) O

OH

(g) C6H5CC

O

CH

Cl

C6H5

(h) [(CH3)3C]3CH

��

(i)

O

C2H5CH3

I

(j) OH

ClO

(k) CH3CH2C

O

O C

O(l) (CH3)3CCOO

(m)

COOH

COOH(n) CH2 CH2 OH3C Na

(o)CH2 CH S NaH3C

CH3(p) CH3

OCN

CH3

CH3

SET-XII: Draw the structures for the following names.

(a) phenyl 2-methylbut-2-enoate (b) 3-aminohept-5-enamide(c) 4-(4 chlorophenyl)pentanoic acid (d) 4-(N,N-dimethylamino)butan-2-ol(e) 4-amino-2,2-dimethyl-4-oxobutanoic acid (f) 1,1,3-triphenylprop-2-en-1-ol(g) 3,3-dimethylhex-4-yn-2-one (h) 2-methylcyclohexane-1,3-dione(i) 6-methylcyclohex-1-ene-1-carbonitrile (j) 3,4-dimethylphenol(k) 2-iodo-1-methoxy-4-methylbenzene (l) potassium ethanethiolate

(m)

SET-XIII: Write the IUPAC names for the following compounds.

(a) CH2(OH)CH(OH)CH2(OH) (b) H3C C

CH3

Br

CH2 COOH

(c) ClCH2CH2Cl (d) H3C CH

Cl

C

Cl

Cl

CH2OH

(e) HO C

O

C

O

OH(f)

H3C CH CH CH CH3

Br

(g) H3C CH CH CHO (h) H3C C CH2 C CH3

O O


(i) CH3

CH3

Cl

O

Cl

(j) CH2 CH C CH CH2

Br

(k) CH3

CH3

CH3

Br

Cl

(l) Cl CH2 C CH C

CH3

CH3

O

(m) H3C C C CH CH CH3

OH

CH3

(n) CH3O CH(CH3)CH CHCOOCH(CH3)2

(o) CH3 CO

CH2 COOH (p) HOOC(CH2)4COOH

(q) H3C CH

CHO

CH CH C

O

Cl(r) CH3CH(OH)CH(CH3)COCH3

(s) PhCH2CH(CH3)COOCH(CH3)CH2CH3 (t) CH2 CH CH2 CH2

Cl

NH2

(u)CH3CH(CH3)CHCH(CH3) C(CH3) CH2

CH CH2(v)

CH CH2OH

Cl

(w) H C

O

CH2 CH C

O

H

CHO(x) (CH3)3CCH(CH3)NHCH(CH3)2

(y) H3C CH

OCH(CH3)CH2CH3

C

CH3

CH CH

NH2

CN(z)

O OH

OH

��

SET-XIV: Write the IUPAC names of the following compounds.

(a) CH3

N

CH3CH3

OH

CH3

COOEt

COOH

(b)

HOOC

O

CH3

COOH

(c) CH3

CH3

(d)

CH3

(e) O

O

O

C H 3

(f)

O

O

CH3O

OH

(g)

OH

CH3

NH

CH3

CH3

(h)

(i)

CH3 CH3

CHO

OH

(j)

CH2

NH2EtOOC

(k) NHCH3

(l)

CH3

N

CH3

CH3

CH3

O

CH3

(m)

NH2

OH

CH3

(n)

NH2

CH3

(o)

CH3

CH3

CH3

CH3


SET XV: Write the IUPAC names of the following.

(i) CH3

CH2

CH3

(ii)

CH2

CH3

O

OH

(iii) CH2

CH2 O

NH

CH3

CH3

(iv)

CH3

CH3

OH

CH3

(v) CH3

Cl Cl

(vi)

NO2

Br

CH3

(vii)

OH

NH2

(viii)CH2

CH3

NCH3 CH3

(ix) H

O

O

CH3

CH3

COOH (x)

CH3

CH3

NH

CH3

CH3

CH3

CH3

(xi)

OH

(xii) CH3

CH(xiii)

OHCCHO

CHO

��

(xiv)

O

OH

(xv) O

CH3 CH3

CH3

SET-XVI:

(a)

CH3 CH3

CH3

CH3 (b)

CH2

CH

CH3

(c)

CH2

CH3

CH3

CH2

CH3

CH3

CH3

(d)PhOOC

COOPh

COOPh

CH3

(e)

COOHCH3

COOMe

(f)

CH3

O CH3

(g)

OCH3

(h)

BrBr

Br

Cl

(i)COOEt

CH3

CH3 CH3

O

CH3CH3

OH

(j)O

COOEt

(k)

OO

CH3

(l)

CH2

SO3HCH3

CH2

(m)

O

O

O

(n)CH3

CH3

NCO


RESPONSE TO SAQs

SAQ.III.1:

(i) pent-4-en-2-ol (ii) 2-methylhex-3-ynoic acid

(iii) 5-hydroxyhexan-3-one (iv)3-amino-2-bromo-5-chloroheptan-4-ol

(v) 2-methyl-5-oxopentanenitrile (vi)2-methyl-3-sulfobutanoic acid

(vii) 7-tert-butoxy-6-formyl-3,5-dimethyl- (viii) 6-chloro-4-methyl-6-oxohex- 7-oxohept-4-enoic acid 1-yne-3-sulfonic acid

(ix) 2-(prop-1-enyl)hexan-1-ol(new); (x) 3-aminopropane-1-thiol 2-butylpent-3-en-1-ol(old)

(xi) 4-sulfanylbutan-2-ol (4-mercaptobutan-2-ol) (xii)7-(isopropylthio)octan-4-ol

(xiii) 4-(3-oxobutyl)hept-5-enoic (xiv)3-(3-ethyl-4-methylpentyl) acid(old); 7-oxo-4-(prop-1-enyl) hept-4-en-2-one(old) octanoic acid(new) 3-(but-1-enyl)-6-ethyl-7-methyloctan-

-2-one(new)SAQ.III.2:

(i)5-cyano-3,4-dimethylpentanamide (ii)3-methyl-5-oxopentanenitrile

SAQ.III.3:(i) 4-ethynyl-2-methyl-5-(1-methylbut-1-enyl)undec-2-en-8-yne(ii) 3-ethynyl-4-methyl-5-methylenehepta-1,6-diene(iii) 3-ethynyl-4-isopropenyl-6-methyldeca-1,3,6-trien-8-yne(1-methylvinyl can beused in place of isopropenyl)(iv) 6-methyl-7-(1-methylethylidene)-4-vinylundeca-2,5,9-triene(v) 6-ethyl-4-methylene-5-(prop-1-enyl)dodeca-7,9-dien-2-yne

SAQ.III.4:

(i) 3-(2-amino-2-oxoethyl)-2,3-dimethylpentanediamide(ii) 3-(2-amino-2-oxoethyl)-6-oxohexanoic acid)(iii) methyl 7-amino-2-(3-amino-3-oxopropyl)-7-oxoheptanoate(iv) heptane-1,3,7-tricarboxamide(v) 4-(aminocarbonyl)-7-oxoheptanoic acid(vi) 9-chloro-5-formyl-6-(methoxycarbonyl)-9-oxononanoic acid(vii) propane-1,2,3-triol(glycerol)(viii) 2-methylnonane-3,5,7-trione(ix) N,N’-dimethylbutane-1,4-diamine(x) pentane-1,1,3-tricarbaldehyde(xi) 3-(2-chloro-2-oxoethyl)hexanedioyl dichloride(xii) 5-ethyl 1-isopropyl 2-methylpentanedioate

(When two alkoxy(OR’) parts of diester are different, each alkyl group is prefixed with thelocant of carboxyl carbon to which the alkoxy group is attached)

��

SAQ.III.5:

(i) CH27

6

5

4

3

2

1

O

O CH3

CN CH3

CH2

(ii) CHO

OHC

OHC

(iii)

O

H

OH

OH

OH

OH

OH

(iv)

CH38

7

6 5 4 3 2

CH21

CH2

CH3CH3CH3

(v)

5

4

3

2

1

O

NH2

O

NH2

1

2

O

NH2

SAQ.III.6:(i) 3-formyl-4-hydroxy-2,2,5-trimethylhexanamide(ii) N-tert-butylbutan-2-amine(iii) 2-isopropoxy-2-methylpropane(iv) 2,7,7,10-tetramethyl-6-oxoundec-8-ynal

SAQ.III.7:(i) 3-(6-methylcyclohex-1-enyl)propan-1-ol(ii) 3-[2-(aminocarbonyl)cyclohexyl]propanoic acid(iii) 4-(3-formylcyclopentyl)-2-methylbutanoic acid(iv) 1-cyclopentylethanol(v) 2-(2,3-dimethylbutyl)cyclobutanol(v) 3-(5-hydroxycyclohex-2-enyl)-2-methylpropanoic acid(vi) 2-(2,2-dimethylbutyl)cyclopropanamine(vii) 1-ethyl-2-propylcyclohexane

SAQ.III.8:(i) ethylbenzene (ii) isopropylbenzene(cumene)(iii) propiophenone(1-phenylpropan-1-one) (iv) ethoxybenzene(v) isopropylbenzoate (vi) iodobenzene(vii) 1,2,3-trimethylbutylbenzene

SAQ III.9:(i) (chloromethyl)benzene(Cl is not a functional group) (ii) 1-phenylmethanamine(iii) methyl 2-phenylacetate (iv) phenylacetonitrile(phenylethanenitrile)(v) 2,3-dimethyl-3-phenylbutanal


SAQ III.10:

3-methylaniline(m-toluidine), 1-chloro-2-nitrobenzene(o-nitrochlorobenzene),3-sulfobenzoic acid, 1-chloro-4-ethylbenzene, 1,2-dinitrobenzene, 1,3-dichlorobenzene, 1-isopropyl-2-nitrobenzene, 4-acetylbenzonitrile, 3-(aminocarbonyl)benzoyl chloride, 1,3-dinitrobenzene,1-bromo-3-iodobenzene, benzene-1,3-dicarbaldehyde, benzene-1,2-dicarboxamide, ethyl 4-cyanobenzoate, 1-ethyl-4-methylbenzene, 2,4-dichlorophenoxyacetic acid

SAQ III.11:

(i) 3-[2-(dimethylamino)phenyl]butanal (ii)2-(2-methylprop-1-enyl)aniline(iii) 3-(1-methyl-2-oxoethyl)benzonitrile (iv)2-(2-formylphenyl)propanoic acid(v) 3-methyl-4-(2-nitrophenyl)but-2-enoic acid

SAQ III.12:

methyl 2-methyl-5-nitrobenzoate, 3-acetyl-5-nitrobenzaldehyde, 4-ethyl-2-methyl-1-nitrobenzene, dimethyl phthalate, 1-bromo-3-chloro-5-iodobenzene, 2-chloro-4-ethoxy-1-methylbenzene, 3,4-dimethyl-2-nitroaniline, 1,2,4-trinitrobenzene, 2-chloro-5-chlorocarbonylbenzoic acid

SAQ.III.13:

3-chloro-1-naphthol, 6-methyl-1-naphthamide, 4-methyl-9-anthrol, 9,10-dichloroanthracene-1-carboxylic acid, 7-amino-2-naphthol

SAQ.III.14:

(i) bicyclo[1.1.1]pentane (ii)bicyclo[2.2.2]oct-2-ene (iii)7-methylbicyclo[4.2.1]non-3-ene(iv)9-ethylbicyclo[3.3.2]decane (v)bicyclo[4.4.2]dodec-11-ene (vi) 8-methylbicyclo[5.2.0]non-2-ene (vii)bicyclo[5.3.1]undec-4-en-2-amine (viii)5-aminobicyclo[4.2.1]non-2-ene-7-carboxylic acid(ix)bicyclo[3.2.2]non-2-en-6-amine (x)bicyclo[3.1.1]hept-2-ene-6-carbaldehyde

SAQ III.15:

(i) 1,4-dimethylspiro[2.7]deca-5,8-diene (ii) 6-isopropylspiro[3.5]non-1-ene(iii) 4-methylspiro[2.2]pent-1-ene (iv)1-chloro-5-ethylspiro[3.3]heptane(v) 4-methylspiro[4.8]trideca-1,7,9-triene

SAQ III.16:

(i) 4-ethyl-2,5-dimethyl-3-oxahexane(3-isopropoxy-2-methylpentane) (ii) 4-tert-butyl-3,5-dimethyl-2-oxaheptane(3-tert-butyl-2-methoxy-4-methylhexane)(iii) 3,3,5-trimethyl-4-oxaoctane([2-tert-pentoxypentane or 2-(1,1-dimethylpropoxy)pentane]

SAQ III.17 : (i)

CH3

NH

CH3

CH3

O

CH3

(ii)

NH

(3-methy-4-(propylamino)pentan-2-one) (piperidine)

��

ANSWER TO PRACTICE QUESTIONS

SET-I:(a) 3,3-dimethylbutan-2-ol (b) 4,4-dimethylpent-2-yne(c) 1-chloro-2,3-dimethylpentane (d) 3,4-dimethylpent-2-ene(e) 3,4-dimethylpentan-2-one (f) ethyl 2,3-dimethylpentanoate(g) 2-ethyl-3,3-dimethylbutanal (h) 2,2-dimethylpropanoyl chloride(i) 3,3,4-trimethylpentanamide (j) N-isopropyl-2-methylpropan-2-amine

SET-II:(a) 2,3,4-trimethylpent-1-ene (b)2-methylpropan-2-ol(c) 2,2-dimethylpropan-1-amine (d)methyl 2,2,3,3-tetramethylbutanoate(e)2,2,3-trimethylbutanal (f)isopropyl 2-methylbutanoate(g)2,2-dimethylpropanoic anhydride (h)2-ethoxypropane(i)2,2,6-trimethylhept-3-yne (j)2,2-dimethylpropanenitrile

SET-III:(a)3-ethyl-4-methylheptan-2-one (b)2-ethyl-3-isopropyl-4-methylhex-

1-ene(old);4-isopropyl-3-methyl- 5-methyleneheptane(new)

(c)2,2-dimethylpentan-3-ol (d)calcium 2,2-dimethylpropanoate(e)N-ethyl-N,2-dimethylpropan-1-amine (f)2,3,3,4,4-pentamethylpentanal(g)4-ethyl-N-isopropyl-5-methylhexanamide (h)4-bromo-2,2,3,5-tetramethylhexane(i)ethyl formate(ethyl methanoate) (j)2,2,3-trimethylbutanoyl bromide(k)methylthioethane(methylsulfanylethane) (l)2,2,4-trimethylpentane-3-thiol

(m)1-isothiocyanato-2,2-dimethylpropane

SET-IV:

(The line structures are drawn. The readers are advised to convert these to structuralformula by attaching C and H atoms wherever required)

(a) CH34

3

2

CH31

OH

CH3CH3

(b) CH35

4

3

2

CHO1

CH3

CH3

(c) CH35

4

3

2

COOH1

CH3

CH3

CH3

(d)CH31

2

CH33

N

CH3CH3

CH3

(e) CH34

32

1

O

Cl

CH3

(f)CH33

2

1

O

O CH3

CH3


(g) CH34

3

2

CH31

O

CH3

CH3

(h) CH35

4

3

2

CH31

O

CH3CH3

(i)CH3

CH3

CH3

(j) CH32

1

O

O

1

O

2

CH33

CH3

SET-V :

(a)5-(1,2,2-trimethylpropyl)nonane (b)3,4-diethyl-2,6-dimethylheptane(c)2-methylpropan-1-ol (d)3,3-dimethylbutanal(e)2-isopropyl-3,4-dimethylpentan-1-ol (f)1-(tert-butoxy)but-2-ene(g)tert-butyl 3-methylbutanoate (h)5-ethyl-3-methyloctane(i)2-methyl-3-methylenepentane[2-ethyl-3-methylbut-1-ene(old)]

SET-VI:

(a) CHO (b)CH36

5

4

3

2

CH1

(c) CH37

6

5

4

3

2

1

OHCH3

(d)

4

3

5

2

1 NH2

(e) 5

6

4

13

2

7

8

O

O (f)HOOC1

2

3

4

5

6

7

COOH8

CH3

CH3

(g)CH31

2

3

4

5

6

7

CH38

CH3

CH3CH3

CH3

(h)1

6

2

5

43

CH3

CH3

(i)

CH31

2

3

4

5

6

7

8

9

10

CH311

1

2

CH33

CH3

CH3

(j)3

2

1

O

NH2

O NH2

O

NH2

��

(k)

2

3

4

5

1

6

7 CH3

(l)2

1

OH

(m)CH31

2

3

4

CH3

CH3

CH35

O

(n) CH3CH3

SCN

CH3CH3

Set-VII:

(a) 3-chloro-2,5-dimethylheptan-4-one (b) 4-hydroxy-5-methylhept-2-en- 6-ynoyl chloride

(c) 3-ethyl-3,5-dihydroxypentanamide (d) 2-amino-4,4-dimethylpentanoic acid

(e) 3-bromo-N-ethyl-3-methylpentanamide (f) 3-(1-hydroxyethyl)-5-methylheptanal

(g) 3-hydroxy-4-methylpent-4-enal (h) 3-amino-5-ethylphenol

(i) 2-ethyl-4-(ethylamino)-2-methylbutanal (j) 3,6,9-trimethyldeca-2,4,6,8-tetraenoic acid

(k) 4-chloro-2-ethylcyclopentanone (l) 5-amino-2-methylcyclohex-2-en-1-one

(m) 5-(1-methylethylidene)deca-1,6-dien-8-yne (n) 3-(1-hydroxy-1-methylethyl)heptane- [5-isopropylidenedeca-1,6-dien-8-yne] 1,5-diol

(o)2-methylpentan-3-one

SET VIII:

(a)

1

2

CH3

O

CH3

CH33 (b)

1 2

4 3

EtOOC

(c)

COOH

Cl

(d)CH35

4

3

2

1

O

O

CH3

CH3

CH3

(e)4 3 2 COOH

1

OCH3

(f) CH3

O

NCH3

Ph


(g)CH39

8

7

6

5

4

3

2

CN1

BrBrBr

(h)

6

1

5

4

2

3

O

CH3

(i)N

CH(CH3)2

CH(CH3)2(CH3)2CH

CH(CH3)2

+

Cl-

(j)

O

CH2

(k)

COOEtEtOOC

CH3

OO

i-Pr

(l)

CH36

5

4

3

2

CH21

CH3O

CH3

(m)

CNCHO

CH3

OH

CH3 (n)OHC COOH

O

CH3

CH3

CH3

SET IX :

(a) 4-methylhex-3-yne (b) isobutoxymethylbenzene(since ether group does not have any precedence as functional group, the compound is named as aromatic)

(c) 5-oxopentanoic acid (d) cyclopropylacetyl chloride(e) N,2,3,3-tetramethylbutan-1-amine (f) chloromethylcyclohexane(g) 1-chloro-1-methylpropyl 4- (h) 4-bromo-2,6,6-trimethylhept-4-enoic acid methylpent-2-enoate(i) 1-nitro-4-vinylbenzene (j) 6-methylcycloocta-1,4-diene(k) isobutyl 5-(isopropylamino)-4 (l) 5-cyano-2,3-dimethylpent-3-enamide -methylpentanoate(m) octa-3,5-diynedioic acid (n) isopropoxycyclopentane(o) 1-methylcyclohexa-1,3-diene (p)2-isocyano-3-methylbutane

SET-X:

(a) CH3

CH3

OH

CH3

CH3

CH3CH3

CH3

(b)CH34

3

2

1

O

O

CH3

CH3

��

(c)5

6

1

2

4

3

O

CH3 CH3

Ph (d)

2

3

1

4

6

5

OH

1

2

CH3

CH3

CH33

CH3

(e)

NH2

NO2

(f)

CH3

CH3

O

CH3

CH3

(g)

CH3

(h) CH3 5

4

3

2

1

O

NHCH3

CH3

CH3

(i) CH38

7

6

5

4

3

2

CH21

CH3

(j)

CH32

1

5 4 3 2

COOH1

6CH3

7

CN

CH38

(5-sec-butyl-6-cyanolhept-5-en-3-ynoic acid)

(k)

O

CH3

CH3

(l)

3 2

4 1

OH

OH

Br

SET-XI:

(a)5-chloro-7-methylocta-2,4,6-trienoic acid (b)5-tert-butyl-8-methylnonane-3,5-diol(c)4,4-dimethyl-3-phenylpentan-2-one (d)1,5-diaminopentan-2-ol(e)ethyl 6-ethyl-2-methoxycyclohex-3- (f)2-isopropoxypentan-3-ol ene-1-carboxylate(g)3-(3-chlorophenyl)-1,2- (h)3-tert-butyl-2,2,4,4-tetramethylpentane diphenylprop-2-en-1-one(i)2-ethyl-3-iodo-6-methylcyclohexanone (j)4-chloro-5-hydroxypentan-2-one(k)cyclopropanecarboxylic (l)cyclohexyl 2,2-dimethylpropanoate propanoic anhydride(m) cyclohex-3-ene-1,2-dicarboxylic acid (n)sodium propan-1-olate(o)sodium butane-2-thiolate (p)1-ethyl-2-methylpropyl cyanate

SET-XII:

(a) CH3

O

OPh

CH3

(b)CH37

6

5

4

3

2

1

O

NH2

NH2


(c)CH35

43

2COOH1

Cl

(d)CH31

2

3

4

N

CH3

CH3

OH

(e) 4

3

2

COOH1NH2

CH3 CH3O(f) 1

2

3

OH

Ph

Ph

Ph

(g)CH31

2

3

4

5

CH36

O

CH3CH3

(h)5

6

4

1

2

3

O

O

CH3

(i)

CN

CH3

(j) CH3

CH3

OH

(k)

OCH3

CH3

I

(l)CH3CH

2SK

SET-XIII:

(a)glycerol(propane-1,2,3-triol (b)3-bromo-3-methylbutanoic acid(c)1,2-dichloroethane (d)2,2,3-trichlorobutan-1-ol(e)oxalic acid(ethanedioic acid) (f)4-bromopent-2-ene(g)but-2-enal (h)pentane-2,4-dione(i) 1-chloro-4-(chloromethyl)-5- (j)3-bromopenta-1,2,4-triene methylhexan-2-one(k)3-bromo-2-chloro-5-methyloctane (l)1-chloro-4-methylpent-3-en-2-one(m)2-methylhex-4-yn-3-ol (n)isopropyl 4-methoxypent-2-enoate(o)3-oxobutanoic acid (p)hexanedioic acid(q)4-methyl-5-oxopent-2-enoyl chloride (r)4-hydroxy-3-methylpentan-2-one(s)sec-butyl 2-methyl-3-phenylpropanoate (t)3-chloro-4-cyclopropylbutan-1-amine(u)4-isopropyl-2,3-dimethylhexa-1,5-diene (v)2-chloro-2-cyclohexylethanol(w)ethane-1,1,2-tricarbaldehyde (x)N-isopropyl-3,3-dimethylbutan-2-amine(y)2-amino-5-sec-butoxy-4-methylhex- (z)6-hydroxycyclohex-2- 3-enenitrile ene-1-carboxylic acid

SET-XIV:

(a) 9-(dimethylamino)-5-(3-ethoxy-3-oxopropyl)-8-(hydroxymethyl)-6-(prop-1-enyl)dec-7-enoic acid

(b) 7-methyl-6-oxooct-4-en-2-ynedioic acid (lowest set of locants for the functional group)(c) 3,9-dimethylbicyclo[4.3.1]decane(d) 4-methylbicyclo[2.2.2]oct-1-ene(e) ethyl 2-oxocyclopentanecarboxylate

��

(f) 2-(ethoxycarbonyl)cyclopentanecarboxylic acid(g) 4-(isopropylamino)-2-methylcyclohexanol(h) spiro[2.2]pentane(i) 4-hydroxy-2-isopropylbenzaldehyde(j) ethyl 3-amino-5-vinylbenzoate(k) butan-1-imine (=NH group is called imine group)(l) N-isopropyl-N,2-dimethylpropanamide(m) 5-amino-2-methylphenol(n) 2-(4-ethylphenyl)ethanamine(o) 3-sec-butyl-1,1-dimethylcyclopentane

SET XV:(i) 4-(but-2-enyl)octa-1,3,6-triene(old),5-(prop-2-enylidene)nona-2,7-diene(ii) 4-(pent-3-enyl)octa-5,7-dienoic acid(old); 4-(buta-1,3-dienyl)non-7-enoic acid(iii) N,2-dimethyl-3-methylenehex-5-enamide(iv) 4-(but-2-enylidene]-2-ethylnona-5,7-dien-1-ol(v) (1,3-dichloropentyl)benzene(vi) 1-bromo-4-ethyl-2-nitrobenzene(vii) 2-aminocyclobutanol(viii) N,N-diethylbut-3-en-2-amine(ix) 2,2-dimethyl-4,5-dioxopentanoic acid(x) N-(1,2,3,4-tetramethylpentyl)hexan-1-amine(xi) cyclohex-2-en-1-ol(xii) hex-4-en-1-yne(xiii) 3-(2-oxoethyl)hexanedial [ 3-(formylmethyl)hexanedial](xiv) 3-(cyclopenta-1,4-dien-1-yloxy)propan-1-ol(xv) 1,7,7-trimethylbicyclo[2.2.1]heptan-2-one

SET XVI:(a) 3-ethyl-5-methylheptane (b)4-methylhex-1-en-5-yne(c)7-ethylidene-3-methyl-5-(1-methylprop- (d)diphenyl 2-methyl-4-(2-oxo-2-2-enyl)-6-vinylundeca-2,4,8-triene phenoxyethyl)heptanedioate(e)4-(2-methoxy-2-oxoethyl)heptanoic acid (f)1-methoxy-4-methylbenzene

(p-methylanisole)(g)3-methoxycyclopentene (h)1,3,5-tribromo-2-chlorobenzene(i)ethyl 5-ethyl-4-(2- hydroxyvinyl)-6-methyl-2-(1-methylprop-1-enyloxy)heptanoate(new);ethyl 4-(1-ethyl-2-methypropyl)-6-hydroxy-2-(1-methylprop-1-enyloxy)hex-5-enoate(old)(j)ethyl 2-oxocyclopentanecarboxylate (k)3-methylbicyclo[2.2.2]octane-2,6-dione(l)3-(buta-1,3-dienyl)-6-methyleneoctane-1-sulfonic acid(new);3-(3-methylenepentyl)hepta-4,6-diene-1-sulfonic acid(old)(m)2,2-dimethylpropanoic 2-ethyl-3,3-dimethylbutanoic anhydride(n)1-isocyanato-3-methylbutane

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IUPAC NOMENCLATURE OF COMPOUNDS CONTAINING MORE …theuranium.org/content-images/organic-nomenclature-III.pdf · associated with greater number of functional groups is taken as the