Direct Assembly of Polysubstituted Furans via C(sp3)-H Bond Functionalization by Using Dimethyl Sulfoxide as a Dual Synthon

An unusual I-2-mediated triple C(sp(3))-H functionalization reaction between aryl methyl ketones and dimethyl sulfoxide to form polysubstituted furans has been developed. In this transformation, dimethyl sulfoxide functions as a dual synthon via C(sp(3))-H functionalization with formation of two C-C bonds, one C-O bond, and one C-S bond in a one-step process. Iodine is crucial as promoter of the reaction, by which a number of ketones could be converted easily into 2,4,5-trisubstituted furans. This provides an extremely simple and expeditious approach to high-value-added, biologically significant O-heterocycles. Based on preliminary experiments, a plausible mechanism is proposed.