PRODUCTION OF GAMMA-ALKOXY-ALPHA-KETO-CARBOXYLIC ACID ESTERS

摘要

PURPOSE:To easily obtain the titled substance by silylating a pyruvic acid ester and reacting the resultant 2-(trialkylsiloxy)acrylic acid ester with an acetal or a ketal in the presence of a Lewis acid. CONSTITUTION:2-(Trialkylsiloxy)acrylic acid ester derived from a pyruvic acid ester and a chlorotrialkylsilane (preferably chlorotrimethylsilane) is made to react with an acetal or a ketal at -78-0 deg.C (usually 0 deg.C) for several min-several hr in the presence of a Lewis acid to obtain the titled substance. The Lewis acid is preferably boron trifluoride etherate and the reaction is carried out preferably by using dichloromethane as a solvent. The titled substance is useful as a synthetic intermediate for a constituent component of a physiologically active substance.