The three-component reaction of dicarbomethoxycarbene, aldehydes, and β-nitrostyrenes: a stereoselective synthesis of substituted tetrahydrofurans

The Rh(II)-catalyzed reaction of dimethyl diazomalonate with aryl aldehydes and β-nitrostyrenes results in the formation of highly substituted tetrahydrofurans. The reaction may be considered to involve the Huisgen dipolar cycloaddition of the carbonyl ylide, generated from the dicarbomethoxycarbene and the aldehyde, to the β-nitrostyrene. The diastereoselectivity of the reaction may be attributed to the concerted nature of the carbonyl ylide cycloaddition