Carboxylic acid and carboxylic acid derivatives Carboxylic acid and carboxylic acid derivatives Dr....

Carboxylic acidand carboxylic acid

derivatives

Dr. Nabila Al Jaber

Carboxylic acid R-COOH Ar-COOH Aliphatic (carboxylic cid) aromatic (benzoic acid)

1) replace ane by -ic acid

Nomenclature :

Common IUPAC Formula No. C

Formic acidAcetic acidPrpionic acidButyric acidvaleric acid

Salicylic acid

Benzoic acid

Methanoic acidEthanoic acidPrpanoic acidButanoic acidPentanoic acid

2-hydroxy ben. a

HCOOHCH3COOH

CH3CH2COOH

CH3(CH2)2COOH

CH3(CH2)3COOH

12345

OH

COOH

COOH

2) Longest continuous chain

CH3CH2CHCH2CH2COOH 4-Methyl hexanoic acid CH3

C-C-C-C-C-COOH

CH3CH2CHCH2CH2COOH γ-Methyl hexenoic acid CH3

CH3-CH-CH-COOHCH3CH3

commmone: -- Dimethyl butyric acidIUPAC: 2,3-Dimethyl butanoic a

CH3-CHBr-CHCl-CO2H

3-Bromo-2-chlorobutnoic acid

3) In cyclic ring ------ cycloalkane carb. a'

COOHCOOH

COOH

cyclopropanecarb.ac.

cyclobutanecarb.ac.

cyclopentanecarb.ac.

cyclohexanecarb.ac.

COOH

COOH 2-Cyclohexene carboxylic acid3

5) Aromatic acid by common name

CO2H CO2H

(comm.) Phthalic a'

(comm.) Terephthalic a'

CO2H

CO2H

CO2H

benzoic acid

OH

CO2H

Salycilic acidO- hydroxy benzoic acid

CH2CH2COOH

3-Phenyl-propionic acid

OH

HOOC

Hydroxy-phenyl-acetic acid

Physical properties

1] They form hydrogen 2] comp. 1-7 soli in H2O . 3] mor than 7 carbon less soli. (bec. R

increased)4] Aromatic acids insoluble. In H2O5] BP. Acid > Alcohol

Deac. gps inc. acidity Acti gps dec. acidity

COOH

NO2NO2

COOH

NO2

COOH COOH

CH3

> > >

inc. acidity

OHCOOH COOH OH

inc acidity

HCOOH > CH3COOH > CH3CH2COOH > CH3 CH2 CH2COOH

More acidity

Substitution with halogen :

CH3CH2COOH < CH2Cl-CH2COOH (more acidic)

CH3CH2COOH < CH2ClCOOH < CHCl2COOH < CCl3COOH

More acidity

Preparation of carboxylic acid

1] Oxidation

a) 1 alcohols & Aldehydes

CH3CH2OH KMnO4 / H+ CH3CHO CH3COOHheat

CH2OH CHO COOH

KMnO4 / H+

or K2Cr2O7 /H+

heat

Preparation of carboxylic acid

RCH2OH

Cu / Heat

or KMnO4 / H+

or CrO3 / pyridineR-CHO

K2Cr2O7 / H+RCOOH

b) of alkyl benzene

CH3 COOH

KMnO4 / H+

or K2Cr2O7 /H+OCH3 OCH3

COOHKMnO4 / H+

or K2Cr2O7 /H+

CH3

NO2 NO2

COOH

KMnO4 / H+

or K2Cr2O7 /H+

CH2CH2CH3

2)Hydrolysis of nitriles

RCN +H2O

R-COOH

RCOO

R-X + NaCNheat

OH

H+

(K,Na,..)

RCH2NH21)Li AL H4, ether

2)H3O or H2 / Pt amine

(K<Na..)

CH3CH2Cl1)NaCN

CH3CH2CN + H2O 2) Hheat

CH3CH2CO2H

CH2Cl

1)NaCN

CH2CN

2) H

heat

CH2CO2H

+ H2O

3] Carbonation of Grignard reagent:

R-Mg X R-COOMgX H3O RCOOHCO21) 2)

CH3-Mg Br CH3-COOMgBr2) H3O

CH3COOH+ Mg(OH)Br

1)CO2

Mg Br COOH

1)CO22) H3O+

Preparation of carboxylic acid

• Hofmann Reaction

• Collb’s Reaction

O

+ NaOHI2

OH

O

+ CHCl3

Reactions of acids

1)Salt formation:

it react with strong base & we can use CaOH, NaOH or KOH

RCOOH + KOH RCOOK + H2O

RCOOH + NaOH RCOONa + H2Osodi. acetate

reaction with weak base

RCOOH + NaHCO3 RCOONa + CO2 + H2O

Sodium bicarb. Can be used to distinguish between carboxylic acid and phenols

OH

+ NaHCO3NO reaction

Reactions of acids

2) Formation of Easter:

RCOOH R'-OH / H+heat R-COO-R' + H2O

OH

COOH

CH3CH2OH OHCOOC2H5H+ / heat

3) Formation of amide:

RCOOH NH3 or R-NH2 ,heat R-CONH2

CH3COOH heatCH3-CONH2

NH3 ,

Reactions of acids

4) Formation of acid anhydride:

2 RCOOH R-C-O-C-RO O

2 CH3CH2COOH CH3CH2-C-O-C-CH2CH3O OH2SO4

H2SO4

5) Formation of acid chloride:

2 RCOOH SOCl3 PCl3 R-C-ClO

2 CH3COOHO

or PCl5

SOCl3 PCl3or PCl5

CH3-C-Cl

,

,

2

2

Reactions of acids

Reactions of acids

Addition anti marco.

OH

O

HBrH2OOH

O

OH

O Br

HH

OH

H+

Nomenclature of carboxylic acid derivatives

When Oxygen of Carboxylic acid is replaced with Nu.------ Carb. a' deriv

OH

O

R

Nu

O

R Nu

O

Ar

R Cl

O

R OR'

O

R N

O OO

R-C-O-C-R

Acid chl. Ester AmideAcid anhydride

R O-(K or Na)

O

Salts

When Oxygen of Carboxylic acid is replaced with Nu.------ Carb. a' deriv

1] Salt:

H3C O- Na

O

Com. Sodium acetate

IU. Sodium etanoate

from Acet.a'.

from Ethan.a'.h

, K

2] Acid chloride

Cl

O

CH3CH2

(Com.) Proanyl chloride from propanoic a'(I) Propionyl chloride from propionic a'

I

Com.

Cl

O

Benzoyl chloride

3] Ester:The alkyl gp. Named 1st then the name of parent acid with ending –ate in place of -ic acid

OCH2CH3

O

CH3(Com.) Ethyl ethanoate from ethanoic a'

(I) Ethyl acetate from acetic a'

I

Com.

OCH3

O

H (Com.) Methyl formate from formic a'(I) Methyl methanoate from mthanoic 'a

O-CH3

O

Methyl benzoate Methyl salisylate

OCH3

O

OH

O-C-CH3

O

CH2-O-C-CH3

O

(I) Phenyl ethanoate(Com.) Phenyl acetate

(I) Benzyl ethanoate(Com.) Benzyl acetate

O-CH=CH2

O

CH3Vinyl acetate

4]Amides:

-oic acid or -ice a' by –amide .f 1 or 2 subst. on nitrogen we say N-subs. or N,N-disubs. (sub. Name 1st )

NH2

O

R NH2

O

ArOr

O

C-NH2Benzamide

NH2

O

CH3CH2Propanamide

C-NCH3

O

CH3C-N

CH3

C2H5

O

(I) N,N-Dimethyl benzamide(I) N,Ethyl-N-methyl benzamide

4] Acid anhydride:

replacing -acid with anhydride

O

C-O-C-R

O

R

O

C-O-C-R

O

Ar

O

C-O-C-CH3

O

CH3 Ethanoic anhydride

O

C-O-C-CH2CH3

O

CH3CH2(I) Propanoic anhydride (C) Propionc anhydride

R-CO-Cl > R-(CO)2O-R > RCO2R > RCO2H > RCONH2

Acid chloride Acid anhydride Ester Acid Amide

Order of reaction:

O

OO

Benzoic acid anhydride

O

O

O

Dihydro-furan-2,5-dione

Succinic anhydride

AMIDES

ESTERS

ANHYDRIDES

Overview Reaction

Reactions of acid derivatives

a) Acid chlorides:

R-C-ClO

R-C-OH + HClO

R-C-OR'O

R-C-NH2

O

R-C-NHR'O

R-C-NO

H2O/ H+

R'OH

NH3

R'NH2

R'2NH

+ HCl

+ HCl

+ HCl

R'

R' + HCl

Reduction:

Cl

O

R

1) Li Al H4 / ether

2) H3OR-CH2OH

B] Acid anhydride:

R-C-O-C-RO

R-C-OHO

R-C-OR'O

R-C-NH2

O

R-C-NHR'O

R-C-NO

H2O/ H+

R'OH

NH3

R'NH2

R'2NH

+ RCOOH

+ RCOOH

+ RCOOH

R'

R' + RCOOH

O

acid

Ester

Amid

2

O

O

R

O

ROH

COOH

O CH3

O

+CH3-COOHCOOH

acetyl salisilic acid + acetc acidCH3CH3

Reduction:

1) Li Al H4 / ether

2) H3O2 R-CH2OHO

O

R

O

R

C] Esters:

RCOOR' + H2O RCOOH + R'OHH+

RCOOR' + R''OH RCOOR'' + R'OHH+

RCOOR' + NH3 RCONH2+ R'OHH+

Reduction:

RCOOR' RCH2OH+ R'OH1)Li Al H4 / ether

2) H3O

CH3CH2CH2OH+ CH3OH1)Li Al H4 / ether

2) H3OCH3-CH2COOCH3

R-C-OO-R' 1) 2 R'' Mg X

2 ) H3O / H+R-C-R''

OH

R''

+ R' OH

d] Amide:R-C-NH2

OR-C-OH + NH3

O

R-C-NH2

OR-C-ONa + NH3

O

+ H2OH+

NaOH / heat

Reduction:

R-C-NH2

O

R-C-NHR'O

1) Li Al H4 / Ether2) H3O

1) Li Al H4 / Ether

2) H3OR-CH2NHR'

R-CH2NH2

R-C-NO 1) Li Al H4 / Ether

2) H3OR-CH2NR'2

R'

R'

Dehydration:O

P2O5

- H2OR-CN nitrileR-C-NH2

Hoffman degradation:

RCH2-C-NH2

O Br2/ NaOH

or NaOBrR-CH2NH2

OBr2/ NaOH

CH3NH2CH3-C-NH2