CF3 SO2 Na as a Bifunctional Reagent: Electrochemical Trifluoromethylation of Alkenes Accompanied by SO2 Insertion to Access Trifluoromethylated Cyclic N-Sulfonylimines

Abstract

An unprecedented electrochemical trifluoromethylation/SO₂ insertion/cyclization process has been achieved in an undivided cell in an atom-economic fashion. The protocol relies on tandem cyclization of N-cyanamide alkenes by using Langlois' reagent as a source of both CF₃ and SO₂ under direct anodically oxidative conditions, in which two C-C bonds, two C-X bonds (N-S and S-C), and two rings were formed in a single operation. This transformation enabled efficient construction of various trifluoromethylated cyclic N-sulfonylimines from readily accessible materials.

Keywords: alkenes; cyclization; electrochemistry; synthetic methods; trifluoromethylation.