Carboxylic acid

A type of organic compound with the general formula RCOOH. Many carboxylic acids occur naturally in plants and (in the form of esters) in fats and oils, hence the alternative name fatty acids. Carboxylic acids with one COOH group are called monobasic, those with two, dibasic, and those with three, tribasic. The methods of preparation are:

1. Oxidation of a primary alcohol or an aldehyde:
RCH₂OH + 2[O] → RCOOH + H₂O

2. Hydrolysis of a nitrile using dilute hydrochloric acid:

RCN + HCl + 2H₂O → RCOOH + NH₄Cl

The acidic properties of carboxylic acids are due to the carbonyl group, which attracts electrons from the C–O and O–H bonds. The carboxylate ion formed, R–COO–, is also stabilized by delocalization of electrons over the O–C–O grouping. Other reactions of carboxylic acids include the formation of esters and the reaction with phosphorus(V) chloride to form acyl halides.