Acid activated Indian bentonite (AAIB) is an excellent catalyst for the esterification of long chain fatty acids with long chain alcohols. The ester constituents of spermaceti (whale wax) and an analogue of jojoba oil are obtained when the reactants with catalyst are exposed to microwave irradiation under solvent-free conditions. ne Indian bentonite is used for such a reaction for the first time. The procedure is essentially pollution-free as virtually no waste material is produced. Esters can also be synthesized by solvent-free alkylations of carboxylic anions under microwave irradiation. A few solvent-free alkylations of carboxylic anions have been reported using tetrabutylammonium bromide (TBAB) as a phase transfer catalyst under microwave irradiation.