A mild and efficient method for esterification and transesterification catalyzed by iodine

Iodine, was found to be a practical and useful Lewis acid catalyst for the esterification of carboxylic acids with alcohols. The high catalytic activity of iodine can be used for the transesterification of esters by different alcohols including tertiary alcohols and sterically hindered primary and secondary alcohols. The method presented is especially effective for simultaneous esterification and transesterification reactions.