Modular assembly of 4-trifluoromethyl substituted 2-imino-1,3-oxathioles via cobalt(II)-based metalloradical catalysis

Abstract

We report herein a cobalt(II) metalloradical-mediated cycloaddition of α-trifluoromethyl-α-diazoketone with isothiocyanate, which led to the modular formation of 4-trifluoromethylated 2-imino-1,3-oxathioles from easily accessible starting materials with high efficiency. Moreover, the high level of functional group compatibility of this protocol has allowed precise late-stage modifications of bioactive and drug-like molecules. Preliminary mechanistic experiments confirm that the catalytic process proceeds via a stepwise radical pathway involving α-Co(III)-alkyl radical intermediate.