Transition metal-catalyzed ring-opening, substitution, and cyclopropanation reactions via vinylcarbene complexes generated from O-propargyl thiocarbamates

We have developed various transition metal-catalyzed vinylcarbene transfer reactions, such as ring-opening, substitution, and cyclopropanation reactions, using O-propargyl thiocarbamates as carbene precursors. Platinum, ruthenium, rhodium, and gold complexes are effective for vinylcarbenoid formation. The highly nucleophilic nature and resonance effect of a thiocarbamoyl moiety readily permit the rearrangement of a thiocarbamoyl moiety from a propargylic position to an adjacent alkynyl carbon to give the intermediary vinylcarbene complexes.