Stereoselective synthesis of sulfonyl-substituted trans-2,3-dihydrofuran derivatives via reaction of arsonium Ylides with α,β-unsaturated ketones

Abstract

Trans-2,3-dihydrofuran derivatives 3 or 4 substituted with a sulfonyl group were prepared with high chemoselectivity and good yields by [1+4]-addition reaction of α,β-unsaturated ketones 1 with arsonium bromide 2 in CH2Cl2 in the presence of potassium carbonate at room temperature. The structures of the products were characterized by IR, MS, 1H NMR, elemental analysis and single crystal X-ray diffraction analysis. A mechanism for the formation of products was also proposed.