Copper-catalyzed 1,2-carboesterification of 1,3-enynes via polarity-matched hydrogen atom transfer

Abstract

The selective and direct transformation and modification of C–H bonds have always been a difficult and hot topic in synthetic chemistry. In recent years, the HAT strategy has been one of the effective methods to achieve this type of reaction. However, the development of a method that can generate both electrophilic and nucleophilic radicals simultaneously, thereby enabling the selective HAT process of C–H bonds with different polarities, has not been well studied. Herein, we describe a Cu-catalyzed radical 1,2-carboesterification reaction of 1,3-enynes in which HAT processes can occur in diverse C–H substrates using electrically different radicals as hydrogen transfer agents. This novel method features a polarity-matched HAT strategy, readily available starting materials, a broad substrate scope, good functional group compatibility, and diverse transformations. Mechanistic studies suggest that this reaction proceeds through a radical-involved pathway.