Copper-catalyzed Larock-type cyclization/debenzylation of yne-allylic esters with aliphatic amines
摘要
Herein, we describe a strategy for constructing pyrroles via a copper-catalyzed [4 + 1] annulation of yne-allylic esters and aliphatic amines. The key innovation of this approach is the development of copper-ammonium intermediates that facilitate selective C–N bond cleavage under mild conditions. This method demonstrates broad applicability, accommodating both aliphatic secondary amines and aliphatic primary amines, while exhibiting excellent tolerance toward a wide range of functional groups. Furthermore, the ease of subsequent transformations underscores its potential utility in the synthesis of bioactive compounds. Preliminary mechanistic investigations suggest the involvement of a copper-ammonium species, providing insight into the reaction’s underlying process.