Organic Chemistry,5th Edition L.G.Wade,Jr. Chapter 20 Carboxylic Acids Jo Blackburn Richland College,Dallas,TX Dallas County Community College District ©2003，Prentice Hall
Chapter 20 Carboxylic Acids Jo Blackburn Richland College, Dallas, TX Dallas County Community College District © 2003, Prentice Hall Organic Chemistry, 5th Edition L. G. Wade, Jr
Introduction The functional group of carboxylic acids consists of a C=O with -OH bonded to the same carbon. Carboxyl group is usually written -COOH. Aliphatic acids have an alkyl group bonded to -COOH. Aromatic acids have an aryl group. Fatty acids are long-chain aliphatic acids. > Chapter 20
Chapter 20 2 Introduction • The functional group of carboxylic acids consists of a C=O with -OH bonded to the same carbon. • Carboxyl group is usually written -COOH. • Aliphatic acids have an alkyl group bonded to -COOH. • Aromatic acids have an aryl group. • Fatty acids are long-chain aliphatic acids. =>
Common Names Many aliphatic acids have historical names. Positions of substituents on the chain are labeled with Greek letters. -C-C-C-C一C-C OH 8 Ph CI O CH:CH2CH2CHCH2COOH CH3CH2CHC-OH β-phenylcaproic acid a-chlorobutyric acid Chapter 20 3 =>
Chapter 20 3 Common Names • Many aliphatic acids have historical names. • Positions of substituents on the chain are labeled with Greek letters. CH3 CH2 CHC Cl OH O -chlorobutyric acid CH3 CH2 CH2 CHCH2 COOH Ph -phenylcaproic acid =>
IUPAC Names Remove -e from alkane(or alkene) name,add -oic acid. The carbon of the carboxyl group is #1. CIO H CH:CH-CHC-OH Ph-c=C H COOH 2-chlorobutanoic acid trans-3-phenyl-2-propenoic acid (cinnamic acid) => Chapter 20
Chapter 20 4 IUPAC Names • Remove -e from alkane (or alkene) name, add -oic acid. • The carbon of the carboxyl group is #1. CH3 CH2 CHC Cl OH O 2-chlorobutanoic acid Ph C H C H COOH trans-3-phenyl-2-propenoic acid (cinnamic acid) =>
Naming Cyclic Acids Cycloalkanes bonded to -COOH are named as cycloalkanecarboxylic acids. Aromatic acids are named as benzoic acids. COOH COOH CH(CH3)2 OH 2-isopropylcyclopentanecarboxylic acid -hydroxybenzoic acid (salicylic acid) => Chapter 20 5
Chapter 20 5 Naming Cyclic Acids • Cycloalkanes bonded to -COOH are named as cycloalkanecarboxylic acids. • Aromatic acids are named as benzoic acids. COOH CH(CH3 ) 2 2-isopropylcyclopentanecarboxylic acid COOH OH o-hydroxybenzoic acid (salicylic acid) =>