PhOCH, H Organic Chemistry,5th Edition L.G.Wade,Jr. COOH insctive Chapter 21 Carboxylic Acid Derivatives Jo Blackburn Richland College,Dallas,TX Dallas County Community College District ©2003，Prentice Hall
Chapter 21 Carboxylic Acid Derivatives Jo Blackburn Richland College, Dallas, TX Dallas County Community College District © 2003, Prentice Hall Organic Chemistry, 5th Edition L. G. Wade, Jr
PhOCH, H Acid Derivatives COOH All can be converted to the carboxylic acid by acidic or basic hydrolysis. Esters and amides common in nature. R8xR8oQRR8。gR8 ,R一C=N RCOX (RCO)20 RCOOR RCONH2 RCN Chapter 21 2
Chapter 21 2 Acid Derivatives • All can be converted to the carboxylic acid by acidic or basic hydrolysis. • Esters and amides common in nature. => R C O X R C O O C O R' R C O O R R C O NH2 R C N RCOX (RCO)2O RCOOR RCONH2 RCN
H Naming Esters COOH inactive Esters are named as alkyl carboxylates. Alky/from the alcohol,carboxylate from the carboxylic acid precursor. CH3 0 CH:CHCH2OCCH; HCOCHa isobutyl acetate 2-methylpropyl ethanoate benzyl formate benzyl methanoate Chapter 21 3
Chapter 21 3 Naming Esters • Esters are named as alkyl carboxylates. • Alkyl from the alcohol, carboxylate from the carboxylic acid precursor. isobutyl acetate 2-methylpropyl ethanoate CH3CHCH2OCCH3 CH3 O HCOCH2 O benzyl formate benzyl methanoate =>
H Cyclic Esters COOH Reaction of-OH and -COOH on same molecule produces a cyclic ester,lactone. To name,add word lactone to the IUPAC acid name or replace the -ic acid of common name with -olactone. H3C 4-hydroxy-2-methylpentanoic acid lactone a-methyl-y-valerolactone CH3 => Chapter 21 4
Chapter 21 4 Cyclic Esters • Reaction of -OH and -COOH on same molecule produces a cyclic ester, lactone. • To name, add word lactone to the IUPAC acid name or replace the -ic acid of common name with -olactone. O O H3 C CH3 4-hydroxy-2-methylpentanoic acid lactone -methyl--valerolactone =>
Amides COOH Product of the reaction of a carboxylic acid and ammonia or an amine. Not basic because the lone pair on nitrogen is delocalized by resonance. :0: H H H CN H H Bond angles around N are close to120°. Chapter 21 5
Chapter 21 5 Amides • Product of the reaction of a carboxylic acid and ammonia or an amine. • Not basic because the lone pair on nitrogen is delocalized by resonance. H C O N H H H C O N H H _ + Bond angles around N are close to 120. =>
PhOCH, H Classes of Amides ·1°amide has one C-N bond(twoN-H) ·2°amide or M-substituted amide has two C-N bonds (one N-H). ·3°amide or M,W-disubstituted amide has three C-N bonds(no N-H). > Chapter 21 6
Chapter 21 6 Classes of Amides • 1 amide has one C-N bond (two N-H). • 2 amide or N-substituted amide has two C-N bonds (one N-H). • 3 amide or N,N-disubstituted amide has three C-N bonds (no N-H). =>
Naming Amides COOH ·For1°amide,drop-icor-oic acid from the carboxylic acid name,add -amide. ·For2°and3°amides,the alkyl groups bonded to nitrogen are named with N- to indicate their position. O CH3 N-ethyl-N,2-dimethylpropanamide CH:CHC-N-CH2CH3 N-ethyl-N-methylisobutyramide CH3 => Chapter 21
Chapter 21 7 Naming Amides • For 1 amide, drop -ic or -oic acid from the carboxylic acid name, add -amide. • For 2 and 3 amides, the alkyl groups bonded to nitrogen are named with Nto indicate their position. CH3 CHC N O CH2 CH3 CH3 CH3 N-ethyl-N,2-dimethylpropanamide N-ethyl-N-methylisobutyramide =>
H Cyclic Amides COOH Reaction of-NH2 and-COOH on same molecule produces a cyclic amide,lactam. To name,add word lactam to the IUPAC acid name or replace the -ic acid of common name with -olactam. 4-aminopentanoic acid lactam -H y-valerolactam CH3 => Chapter 21 8
Chapter 21 8 Cyclic Amides • Reaction of -NH2 and -COOH on same molecule produces a cyclic amide, lactam. • To name, add word lactam to the IUPAC acid name or replace the -ic acid of common name with -olactam. N O CH3 H 4-aminopentanoic acid lactam -valerolactam =>
PhOCH,C Nitriles CH H COOH cylated .-C=N can be hydrolyzed to carboxylic acid,so nitriles are acid derivatives. Nitrogen is sp hybridized,lone pair tightly held,so not very basic.(pK about 24). acetonitrile propyne Cnapter21 9
Chapter 21 9 Nitriles • -CN can be hydrolyzed to carboxylic acid, so nitriles are acid derivatives. • Nitrogen is sp hybridized, lone pair tightly held, so not very basic. (pKb about 24). =>
PhOCH, CH Naming Nitriles COOH For IUPAC names,add -nitrile to the alkane name. Common names come from the carboxylic acid.Replace -ic acid with -onitrile. Br C≡N CH:CHCH-CH2CH2CN 5-bromohexanenitrile -bromocapronitrile Cyclohexanecarbonitrile => Chapter 21 10
Chapter 21 10 Naming Nitriles • For IUPAC names, add -nitrile to the alkane name. • Common names come from the carboxylic acid. Replace -ic acid with -onitrile. CH3 CHCH2 CH2 CH2 CN Br 5-bromohexanenitrile -bromocapronitrile C N Cyclohexanecarbonitrile =>