Abstract The title carbenes 5 can be generated either from diazo compounds 9 by copper- catalyzed catalysis or from chloro (organylthio) methylsilanes 12 by base-induced α- elimination. This is confirmed by [2+ 1] cycloadditions with alkenes to give the cyclopropanes 4a–d and 14. Product 4a is identical with the product obtained from carbanion 1c, phenyloxirane, and styrene, for which a carbene intermediate 5a had been ...
