PRODUCTION OF PIVALOYLACETIC ESTER

摘要

PURPOSE:To obtain a pivaloylacetic ester from pinacolone and a dialkyl carbonate in high yield and at a low cost by raising the reaction temperature by using a hydrocarbon solvent having a relatively high boiling point in the presence of an excessive amount based on pinacolone of a metal alcoholate and further distilling away a formed alcohol. CONSTITUTION:Pinacolone is reacted with a dialkyl carbonate in a hydrocarbon solvent (especially preferably an alkyl-substituted aromatic hydrocarbon) having a relatively high boiling point in the presence of an excessive amount by an equivalent ratio based on pinacolone of a metal alcoholate (especially preferably sodium methoxide) while distilling away a formed alcohol to give a pivaloylacetic ester. The amount of the metal alcoholate is preferably 1.5-2 equivalent based on 1 equivalent of pinacolone and the reaction temperature is preferably about 90-120 deg.C. The pivaloylacetic ester is a very important compound as an intermediate for synthesizing a photographic material. By this method, the objective compound can be produced by a simple one-stage reaction in high yield and at a low cost by using the inexpensive metal alcoholate and the inexpensive solvent.