Deoxygenative Cyclopropanation of Aldehydes with Acyl-Stabilized Sulfur Ylides.

Herein, we described a novel [1+1+1] deoxygenative cyclopropanation between sulfur ylides and aldehydes, which is distinctive from traditional epoxidation reactions. The method offers a straightforward approach for the synthesis of highly stereoselective, functionalized, and structurally diverse tertiary cyclopropyl thioethers. The reaction demonstrates a broad substrate scope and excellent compatibility with various functional groups, rendering it particularly suitable for the late-stage modifications of pharmaceuticals and natural products, as well as the synthesis of structurally diverse compounds. Additionally, β,β-disubstituted enals can also engage in the deoxygenative cyclopropanation reaction, instead of undergoing classic cyclopropanation through a Michael addition reaction-induced cyclization with sulfur ylides, thus yielding synthetically important vinylcyclopropanes with excellent chemoselectivity and diastereoselectivity.