Synthesis of 2,3-Dihydropyrrolizines from Weinreb 3-(Pyrrolidin-2-ylidene­)propionamides or Weinreb N-Vinylprolinamides

Abstract

Weinreb 3-(pyrrolidin-2-ylidene)propionamides and Weinreb N-vinylprolinamides were used for the synthesis of 2,3-dihydropyrrolizines. The selective reaction of the carboxamide group with organometallic compounds allowed us to obtain a great variety of carbonyl intermediates, analogous to the Hantzsch and Knorr pyrrole synthesis, which were thermally cyclized.

Weinreb amides - cyclizations - amines, pyrroles - bicyclic pyrrolizines

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