Microwave-assisted dealkoxycarbonylation of alpha-mono- and alpha,alpha-disubstituted beta-keto- and alpha-cyanoesters mediated by a silica gel bed

A new alternative protocol for the classical Krapcho reaction is reported herein, involving a microwave-assisted method, which replaces the typical aprotic polar solvent with a silica gel support along with the addition of only a few mL of DMF to enhance the effects of microwave irradiation. This experimental procedure was successfully applied to several alpha-mono-and alpha,alpha-disubstituted beta-ketoesters and alpha-cyanoalkylesters, allowing rapid isolation of the corresponding ketones and nitriles with moderate to high yields in short reaction times.