5.10 Structure of Esters An ester is a carboxylic acid with the acidic H replaced with an R group

5 4 3

5.11 Preparation of esters Esters are produced from the condensation of a carboxylic acid and alcohol

Preparation of esters movie D:\Movies\ester acid esterification.mov

Fig Naming esters Alcohol name + acid root “ate” Esters have an alcohol part and an acid part NAME:

Table 5.4 Esters that are used as flavoring agents

5.13 Common Esters 1.Alcohol 2.Acid

5.14 Isomerism in Carboxylic acids and esters Constitutional isomers exist between carboxylic acids and esters Constitutional isomers exist between esters

Table 5.5 Boiling points of compounds with similar molecular weights 5.15 Physical properties of esters

Fig Ester-water hydrogen bonding

→Fig Methyl and ethyl esters of unbranched-chain carboxylic acids at room temperature and pressure. Carboxylic Acids, Esters, and Other Acid Derivatives cont’d

5.16 Reactions of Esters Hydrolysis Reactions 1. Acid hydrolysis

2. Base hydrolysis (saponification) Movies\ester base hydrolysis.mov

5.17 Sulfur analogs of esters E.g., Acetyl coA 5.18 Polyesters…..skip

5.19 Acid anhydrides Acid anhydrides can be organic or inorganic or both 1. Organic 2. Inorganic

3. Organic and inorganic 1,3-bisphosphoglycerate Mixed anhydride bond Phosphate ester bond Glyceric acid

5.20 Esters of inorganic acids Custom Medical Stock Photo