Copper-Catalyzed Cleavage of Unstrained C–C Bonds for the Synthesis of 1-Acyloxy-2,2,6,6-tetramethylpiperidines from Cyclic or Acyclic Ketones

Abstract

A copper-catalyzed approach for the synthesis of 1-acyloxy-2,2,6,6-tetramethylpiperidines through the C–C bond cleavage of cyclic or acyclic ketones was developed. In this chemistry, a combination of CuCl₂·2H₂O, 1,10-phenanthroline monohydrate, and aniline was crucial for the formation of the desired products by the reaction of ketones with TEMPO. This research provides a new strategy for the further transformation of α-aryl cyclic or acyclic ketones.

Key words

copper catalysis - acyloxypiperidines - C–C bond cleavage - ketones - TEMPO

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