An Electrocatalytic Approach to the Radical Difunctionalization of Alkenes

作者：Sauer, Gregory S.; Lin, Song^*

来源：ACS Catalysis, 2018, 8(6): 5175-5187.

DOI：10.1021/acscatal.8b01069

• electrocatalysis
• electrosynthesis
• electrochemistry
• alkene difunctionalization
• vicinal diamine
• dichlorination
• trifluoromethylation
• radical addition

Given its many distinct characteristics, electrochemistry represents an attractive approach to meet the prevailing trends in organic synthesis. In particular, electrocatalysis-a process that integrates electrochemistry and small-molecule catalysis has the potential to substantially improve the scope of synthetic electrochemistry and provide a wide range of useful transformations. Recently, we have demonstrated new catalytic approaches that combine electrochemistry and redox-metal catalysis for the oxidative difunctionalization of alkenes to access a diverse array of vicinally functionalized structures. This Perspective details our design principles underpinning the development of electrochemical diazidation, dichlorination, and halotrifluoromethylation of alkenes, which were built on foundational work by others in the areas of synthetic electrochemistry, radical chemistry, and transition-metal catalysis. The introduction of redox-active Mn catalysts allows the generation of radical intermediates from readily available reagents at low potentials under mild conditions. These transition metals also impart selectivity control over the alkene functionalization processes by functioning as radical group transfer agents. As such, our electrocatalytic difunctionalization reactions exhibit excellent chemoselectivity, broad substrate scope, and high functional group compatibility. Specifically, anodically coupled electrolysis, an approach that pairs two single electron oxidation events in a parallel manner, enables the development of regio- and chemoselective heterodifunctionalization of alkenes. The products of the new transformations we describe in this Perspective represent pertinent structures in numerous medicinally relevant compounds. We anticipate that the design parameters presented here are general and will provide a platform for the development of electrocatalytic systems for other challenging organic redox transformations.

• 出版日期2018-6