Diastereoselective michael initiated ring closure on vinyl sulfone-modified carbohydrates: a stereospecific and general route to alpha-substituted cyclopropanes.

Suitably designed vinyl sulfone-modified furanosides act as substrates for Michael initiated ring closure reactions yielding cyclopropanated carbohydrates. The strategy is general in nature and gives access to cyclopropanes with predefined chiralities on three consecutive carbons with varying substitutions at the alpha-position.