A mild and convenient one-pot two-step synthesis of hydroxyiminodihydrobenzofurans mediated by silica gel under microwave activation conditions

A convenient one-pot two-step procedure for the synthesis of hydroxyiminodihydrobenzofurans assisted by microwave irradiation in presence of silica gel is described herein. Cyclic 1,3-dicarbonyl compounds reacted smoothly with various nitroolefins to furnish hydroxyiminodihydrobenzofuran derivatives as the mixture of E and Z isomers. Clean reaction conditions, no work-up procedure, easy isolation and good yields of the products are the salient features of the methodology. (C) 2010 Elsevier Ltd. All rights reserved.