13.9: Preparation of Carboxylic Acids: Overview
There are various methods for the preparation of carboxylic acids. For example, oxidation of primary alcohols or aldehydes using strong oxidizing agents results in a carboxylic acid. Aldehydes can also be oxidized in the presence of mild oxidizing agents.
Alkyl benzenes, bearing at least one benzylic hydrogen, can be oxidized using KMnO4 or Na2Cr2O7 to yield benzoic acid exclusively. The reaction is carried out under vigorous conditions such as heat and high oxidant concentration.
When internal alkynes are treated with concentrated KMnO4 or, upon ozonolysis, undergo oxidative cleavage to yield carboxylic acids. In comparison, terminal alkynes release CO2 along with the generation of the acid.