Some Chemical Properties of Carboxylic Acids

Most of the reactions of carboxylic acids belong to one of four principal classes, depending on the point in the molecule where the reaction occurs. 

Reactions involving the O-H bond—these include acid dissociation and solvolytic reactions. 

Reactions at the carbonyl carbon—most of which involve attack by a nucleophile Nu on the carbonyl carbon with subsequent cleavage of a C-O bond. Examples are esterification, acyl chloride formation, and reduction with hydrides. 

Decarboxylation—these are reactions in which the R-C bond is broken in such a way that C02 is lost and R-H is formed. 

Substitution on the R group—substitutions for hydrogen or halogen at the 2-carbon are especially important. 

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