To provide a method for producing a (thio)ester condensate by catalytic esterification between equimolar amounts of a carboxylic acid and an alcohol or by catalytic thioesterification between a carboxylic acid and an equimolar or small excess amount of a thiol, thus hopeful as an industrial method needing mass synthesis from the standpoint of green chemistry.
This method for producing a (thio)ester condensate comprises the following process: a direct condensation reaction is made between a carboxylic acid and an equimolar amount of an alcohol or a small excess amount of a thiol in a nonpolar solvent such as toluene in a deoxygenation atmosphere under reflux while heating in the presence of a (poly)condensation catalyst consisting of a tetravalent hafnium compound represented by hafnium (IV) chloride, especially hafnium (IV) chloride.(THF)2 or hafnium (IV) t-butoxide to synthesize the objective monomeric (thio)ester or poly(thio)ester; wherein it is preferable that in making the reflux under heating using the nonpolar solvent, the azeotropic water is eliminated from the reaction system.
YAMAMOTO TAKASHI
