Chapter 16 Carboxylic Acids and Esters 16 1

Carboxylic Acids A carboxylic acid § contains a carboxyl group, which is a carbonyl group (C═O) attached to a hydroxyl group (—OH) § has the carboxyl group on carbon 1 General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 2

Some Typical Carboxylic Acids General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education,

Guide to Naming Carboxylic Acids General, Organic, and Biological Chemistry Copyright © 2010 Pearson

Example of Writing IUPAC Names for Carboxylic Acids To write the IUPAC names of a carboxylic acid STEP 1 Replace the e in the alkane name with oic acid. CH 4 Methane HCOOH Methanoic acid CH 3—CH 3 Ethane CH 3—COOH Ethanoic acid STEP 2 Locate and name substituents, counting from the carboxyl carbon as carbon 1. General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 5

Common Names for Simple Carboxylic Acids The common names of simple carboxylic acids § are formic acid (1 C), acetic acid (2 C), propionic acid (3 C), and butyric acid (4 C). § Examples: HCOOH CH 3—COOH Methanoic acid Ethanoic acid (formic acid) (acetic acid) General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 6

Common Names for Carboxylic Acids The common names of carboxylic acids § use letters , , or to indicate locations of substituents 3 -Methylbutanoic acid ( -methylbutryic acid) General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 7

Alpha Hydroxy Acids Alpha hydroxy acids (AHAs) § occur naturally in fruit, milk, and sugarcane § are used in skin care products General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 8

Common Carboxylic Acids Methanoic acid (formic acid) Ethanoic acid (acetic acid) General, Organic, and

Aromatic Carboxylic Acids Benzoic acid § is the aromatic carboxylic acid § locates substituents by assigning 1 to the carbon attached to the carboxyl group § has common names that assign prefixes ortho-, meta-, and para- for 2 substituents ortho (o) 1, 2 location meta (m) 1, 3 location para (p) 1, 4 location General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 10

Aromatic Carboxylic Acids (continued) General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education,

Learning Check Give the IUPAC and common names for each of the following: A.

Solution Give the IUPAC and common names for each of the following: A. Ethanoic acid (acetic acid) 2 -Methylpropanoic acid ( -methylpropionic acid) B. C. 2 -Bromobenzoic acid (o-bromobenzoic acid) General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 13

Learning Check Give the IUPAC and common names for the following: A. B. C.

Solution A. Propanoic acid (propionic acid) B. 3 -Methylbutanoic acid ( -methylbutyric acid) C. 3 -Bromobenzoic acid (m-bromobenzoic acid) General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 15

Preparation of Carboxylic Acids Carboxylic acids are prepared § by oxidizing primary alcohols or aldehydes § from the oxidation of ethanol, which produces ethanoic acid (acetic acid) General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 16

Learning Check What alcohol would be used to prepare the following: 1. Butanoic acid

Solution What alcohol would be used to prepare the following: [O] 1. Butanol butanal butanoic acid [O] 2. 1 -Propanol propanal propanoic acid General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 18