Esterification of carboxylic acids by tributyl borate under solvent- and catalyst-free conditions
A new method for esterification of mono- and dicarboxylic acids by tributyl borate has been reported. The esterification reactions have been cleanly carried out in the absence of any solvent under catalyst-free conditions. Boric acid is the only side product, which precipitates during the reaction and can be re-used in the production of tributyl borate. Important mono- and dibutylesters, which have found wide applications as plasticizers and ester base lubricants, were prepared by this manner.