Asymmetric Synthesis of Chiral Cyclopropanes from Vinyl Sulfoxonium Ylides Catalyzed by a Chiral-at-Metal Rh(III) Complex.

A chiral-at-metal Rh(III) complex-mediated [2+1] cyclization of vinyl sulfoxonium ylides with α,β-unsaturated 2,2-acylimidazoles has been demonstrated for the first time. This work provides a practical approach for assembling 1,2,3-trisubstituted chiral cyclopropane with alkyl structural units, which had advantages such as a wide range of substrates, good functional group tolerance, and mild reaction conditions. In addition, further amplification experiments and transformation of cycloaddition products were carried out to highlight the practicality of the method.