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Introduction to Organic Chemistry

Chem Olympiad Imine-Carbonyl

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Page 1: Chem Olympiad Imine-Carbonyl

Introduction to Organic Chemistry

Page 2: Chem Olympiad Imine-Carbonyl

NomenclatureWriting form: Prefix – parent – locant – SuffixSteps:1. Parent hydrocarbon2. Number the atoms in main chain3. Identify and number substituents4. Write the name as a single word5. (cycloalkane– chair conformation)

Page 3: Chem Olympiad Imine-Carbonyl

Number of “C” atoms Word root

1 meth

2 Eth

3 Prop

4 But

5 Pent

6 Hex

7 Hept

8 Oct

9 Non

10 Dec

Page 4: Chem Olympiad Imine-Carbonyl

Functional Group Representation

Alkane C-C single bond

Alkene C-C double bond

Alkyne C-C triple bond

Carboxylic acid -COOH

Alcohol -OH

Page 5: Chem Olympiad Imine-Carbonyl

Nomenclature

13 24

13 24

2, 3-dimethybutane

Page 6: Chem Olympiad Imine-Carbonyl

Questions:

Cyclobutane

1-bromo-1-chlorobutane

2,2-dimethylpentane

Page 7: Chem Olympiad Imine-Carbonyl

1,1- dimethylcyclopentane

1,4-dimethylcyclohexane

Page 8: Chem Olympiad Imine-Carbonyl

Lines• Bonds to atoms above the plane of the drawing

(coming out, toward the viewer) are shown with a bold wedge ( ), with the narrow end of the wedge starting at the stereogenic center.

• Bonds to atoms below the plane (going in, away from the viewer) are shown with hash wedges ( ).

Page 9: Chem Olympiad Imine-Carbonyl

Sawhorse representation and Newman projection

Sawhorse representation Newman Projection

Views C-C bond from an oblique angle Views C-C bond directly end-on

Indicated spatial relationships by showing all the C-H bonds

Carbon atoms are represented by a circle

Available: http://image.wistatutor.com/content/hydrocarbons/newman-projections.gif

Page 10: Chem Olympiad Imine-Carbonyl

Staggered and eclipsed

Sawhorse projection

Newman projection

Page 11: Chem Olympiad Imine-Carbonyl

Stability

Page 12: Chem Olympiad Imine-Carbonyl

Skeletal structures

Cyclohexane

Propene

Page 13: Chem Olympiad Imine-Carbonyl

Benzene

Page 14: Chem Olympiad Imine-Carbonyl

Benzene and phenyl• The benzene ring• All aromatic compounds are based on benzene, C6H6, which has a ring of

six carbon atoms and has the symbol:• Each corner of the hexagon has a carbon atom with a hydrogen attached.

• The phenyl group• A hydrogen is removed from a benzene ring, C6H6. Like a methyl or an

ethyl group, a phenyl group is always attached to something else (not carbon).

Page 15: Chem Olympiad Imine-Carbonyl

Benzene-1,4-dicarboxylic acid

2-hydroxybenzoic acid

2,4,6-trichlorophenol

Page 16: Chem Olympiad Imine-Carbonyl

Functional group

• A group of atoms whose bonding is the same from molecule to molecule.

• Imparts similar chemical and physical properties to the molecules which contain them.

Page 17: Chem Olympiad Imine-Carbonyl

Imine Functional Group

Also called Schiff Base=NH

Page 18: Chem Olympiad Imine-Carbonyl

Imine

• Carbon–nitrogen double bond• Nitrogen attached to a hydrogen atom (H) or

an organic group.• The carbon has two additional single bonds

Page 20: Chem Olympiad Imine-Carbonyl

• Related to ketones and aldehydes by replacement of the oxygen with an NR group

• When R = H, the compound is a primary imine • When R is hydrocarbyl, the compound is a

secondary imine

Imines

Page 21: Chem Olympiad Imine-Carbonyl

R2C=NR'

• When R3 is OH, the imine is called an oxime

• When R3 is NH2 the imine is called a hydrazone

Page 22: Chem Olympiad Imine-Carbonyl

Aldimines and ketimines• A primary imine in which C is attached to both

a hydrocarbyl and H is called a primary aldimine

• A secondary imine with such group is called a secondary aldimine

Page 23: Chem Olympiad Imine-Carbonyl

• A primary imine in which C is attached to two hydrocarbyls is called a primary ketimine

• A such group is called a secondary ketimine.

Page 24: Chem Olympiad Imine-Carbonyl
Page 25: Chem Olympiad Imine-Carbonyl

Naming Imines

• Imines are systematically named by adding the word imine after the name of the corresponding aldehyde or ketone

• CH3CHNH

• ethanal imine (from ethanal, CH3CHO) • Btw, is this a primary/secondary

aldimine/ketamine?

Page 26: Chem Olympiad Imine-Carbonyl

Naming Imines

• (CH3)2CNH• Propanone imine • Ethanal methyl imine• CH3CHNCH3

Page 27: Chem Olympiad Imine-Carbonyl

Nitrile

–C≡N

Page 28: Chem Olympiad Imine-Carbonyl

Nitriles

• any organic compound that has a –C≡N functional group

• Inorganic compounds containing the -C≡N group are not called nitriles, but cyanides

Page 29: Chem Olympiad Imine-Carbonyl

Naming Nitriles

• 2 ways of naming nitriles

Page 30: Chem Olympiad Imine-Carbonyl

Cyano substituent style

- The root name is based on the longest chain with the -C≡N as a substituent.

- Chain is numbered so as to give the -C≡N group the lowest possible locant number

- E.g.

1-cyanopropane

Page 31: Chem Olympiad Imine-Carbonyl

Nitrile Style

• The nitrile suffix is used in a very similar manner to carboxylic acids

• Faced with same compound, CH3CH2CH2C≡N• Functional group is a -C≡N, therefore suffix = -

nitrile• Hydrocarbon structure is an alkane therefore –

Longest chain is C4• Butanenitrile

Page 32: Chem Olympiad Imine-Carbonyl

Naming Nitriles (nitrile style)

• Benzonitrile

• Cyclopentanecarbonnitrile

Page 33: Chem Olympiad Imine-Carbonyl

Naming Nitriles

• Butanedinitrile

• 2-methyl-1-propanenitrile• Bonus! How do you name this?

Page 34: Chem Olympiad Imine-Carbonyl

Nitro Functional Group

RNO2

Page 35: Chem Olympiad Imine-Carbonyl

Nitro Functional Group• O-N=O• central nitrogen atom is involved in both a

double bond and a single bond• Highly explosive, various impurities or

improper handling can easily trigger a violent exothermic decomposition (aka an explosion)

• An example is nitroglycerin

Page 36: Chem Olympiad Imine-Carbonyl

Nitro R-NO2

• Aromatic nitro compounds.• Trinitrotoluene (TNT)- A pale yellow, solid organic nitrogen

compound used chiefly as an explosive, prepared by stepwise nitration of toluene

Page 37: Chem Olympiad Imine-Carbonyl

Reactions: Reduction

• Nitro compounds are reduced to amines• RNO2 + 3 H2 → RNH2 + 2 H2O

Page 38: Chem Olympiad Imine-Carbonyl

Naming Nitro Compounds

• Simply name the -NO2 as a nitro substituent

Page 39: Chem Olympiad Imine-Carbonyl

Naming Nitro Compounds

• Nitromethane• Guess how Nitrobenzene looks like?

Page 40: Chem Olympiad Imine-Carbonyl

Thiol Functional Group

Page 41: Chem Olympiad Imine-Carbonyl

Thiols

• Organosulfur compound that contains a carbon-bonded sulfhydryl (-C-SH or R-SH) group

• Have a foul smell• Structurally similar to an alcohol but contains

a sulfur atom in place of the oxygen atom normally found in an alcohol.

• Among the odorous principles in the scent of skunks and of freshly chopped onions

Page 42: Chem Olympiad Imine-Carbonyl

Synthesis

• Reaction of related alcohol with hydrogen sulphide

• CH3OH + H2S → CH3SH + H2O

Page 43: Chem Olympiad Imine-Carbonyl

Naming Thiols

• Sulfur analogues of alcohols• Named the same way too• The root name is based on the longest chain

with the -SH attached.• The chain is numbered so as to give the thiol

unit the lowest possible number. • The thiol suffix is added after the hydrocarbon

suffix : e.g.  -ane + -thiol = -anethiol or -ene + thiol = -enethio

Page 44: Chem Olympiad Imine-Carbonyl

Naming Thiols• CH3CH(SH)CH3

• Propan-2-thiol or 2-propanethiol

• 1-Butanethiol

• Cyclopentanethiol

Page 45: Chem Olympiad Imine-Carbonyl

Naming Thiols

• 4-methylpentan-2-thiol

Page 46: Chem Olympiad Imine-Carbonyl

Sulphide Functional Group

Also known as Thioether

Page 47: Chem Olympiad Imine-Carbonyl

Sulphides

• S atom bonded to two C atoms via s bonds• R-S-R• Named the same way as oxygen cousins,

ethers• Like many other sulfur-containing compounds,

volatile thioethers characteristically have foul odors

Page 48: Chem Olympiad Imine-Carbonyl

Naming Sulphides: "Simple" thioethers

• "Simple" thioethers• If both groups are simple alkyl groups, then

the thioether is usually named as alkyl alkyl thioether

• Alkyl groups are listed in alphabetical order• If the two alkyl groups are the same, then it's

a dialkyl thioether• CH3-S-CH3 Dimethylsulphide

• CH3CH2SCH3

Ethyl Methyl Sulphide

Page 49: Chem Olympiad Imine-Carbonyl

Intermediate Thioethers

• If one of the groups is more complex then the thioether group is usually treated as an alkylthio- (i.e. R-S-) substituent.

• The more complex group (i.e. longer chain, more branched, other substituents) defines the root

• CH3CH2CH2SCH3

1-methylthiopropane

Page 50: Chem Olympiad Imine-Carbonyl

Complex Thioethers• If both groups are complex then the ether can

be named using –thio• E.g. CH3SCH2CH2CH3

• Hydrocarbon structure is an alkane Functional group is an thioether, therefore prefix = -thio-

• The longest continuous chain (including the S)  is 5 therefore root = pent

• Numbering from the left as drawn to make the thio group locant 2-

• 2-thiopentane

Page 51: Chem Olympiad Imine-Carbonyl

Examples (Simple)

• Butyl ethyl sulphide

Page 52: Chem Olympiad Imine-Carbonyl

Disulphides

Page 53: Chem Olympiad Imine-Carbonyl

Disulphide bond

• Covalent bond, usually derived by the coupling of two thiol groups

• Also known as sulphide bridge

Page 54: Chem Olympiad Imine-Carbonyl

Disulphide Bond

• Play an important role in the folding and stability of proteins

• E.g. two-amino-acid peptide cystine• Composed of two cysteine amino acids joined

by a disulfide bond

Page 55: Chem Olympiad Imine-Carbonyl

Ever wondered why hair doesn’t seem to decompose along with dead bodies?

• Over 90% of the dry weight of hair comprises proteins called keratins from the amino acid cysteine

• Hair has a high disulfide content• The robustness conferred in part by disulfide

linkages• Recovery of virtually intact hair from ancient

Egyptian tombs