Synthesis of Polysubstituted Pyrroles via (2 + 2 + 1) Cyclization of Enone Oxime Ethers with Alkynes and Diaziridinone
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Updated: Jan 13, 2026

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Qing-Ying Zeng1,2, Yun-Qian Zhang3,2, Xiao-Ya Cheng4
1School of Pharmaceutical Science and Technology, Hangzhou Institute of Advanced Study, Hangzhou 310024, China.
Abstract:
Herein, we report an efficient palladium-catalyzed (2 + 2 + 1) cyclization strategy for the synthesis of polysubstituted pyrroles from enone oxime ethers, alkynes, and diaziridinone. This transformation is proposed to proceed through a cascade process involving C-C bond cleavage, migratory insertion of alkyne into the C-Pd bond, C-H activation, and subsequent amination with diaziridinone. Notably, this protocol enables the direct incorporation of bioactive fragments into the pyrrole skeleton, highlighting its synthetic utility in medicinal chemistry applications.
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