Preparation of Cyclic N-tert-Butylsulfonyl Enamines by Rh(II)-Mediated Ring Expansion of α-Diazoesters

Abstract

The anion derived from ethyl diazoacetate adds to N-tert-butylsulfonyl ketimines to give β-tert-butylsulfonylamino α-diazo­esters, which are further transformed into cyclic enamines by treatment with Rh₂(OAc)₄, through 1,2-C-C bond migration of a Rh(II) carbene intermediate.

Key words

diazo compounds - Rh(II) carbene - 1,2-C-C bond migration - ring expansion

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