Silica-Supported Tetramethylguanidine: An Efficient Solid Base for Aldol-Type Coupling of Aldehydes with Ethyl Diazoacetate

Abstract

Silica-supported tetramethylguanidine catalyst was prepared and effectively used in the aldol-type coupling of aldehydes with ethyl diazoacetate to afford the corresponding α-diazo-β-hydroxy esters in good to excellent yields. The catalyst was quantitatively recovered from the reaction by a simple filtration and reused for a number of cycles with almost consistent activity.