Electrochemical Difunctionalization of Alkenes

The electrochemical alkene difunctionalization reaction has become a powerful and sustainable tool for the efficient construction of vicinal difunctionalized structures in organic synthesis. Since only electrons are used as the redox agents, electrochemical alkene difunctionalization avoids the need for additional redox catalysts, metal catalysts, or chemical oxidants and does not generate chemical waste. Herein we summarize the latest contributions in the electrochemical difunctionalization of alkenes over the last 3-4 years. We discuss in detail the reaction features, scope, limitations, and mechanistic rationalizations of three categories of alkene difunctionalization methods: (1) electrochemical alkene difunctionalization terminated by nucleophiles, (2) electrochemical difunctionalization of alkenes terminated by radicals, and (3) electrochemical alkene difunctionalization terminated by functionality migration. 1 Introduction 2 Electrochemical Alkene Difunctionalization Terminated by Nucleophiles 2.1 Sulfonylative Difunctionalization of Alkenes 2.2 Sulfurizative/Sulfoxidative Difunctionalization of Alkenes 2.3 Azidotetrazolation of Alkenes 2.4 Trifluoromethylative Difunctionalization of Alkenes 2.5 Diarylation of Alkenes 3 Electrochemical Difunctionalization of Alkenes Terminated by Radicals 3.1 Direct Radical-Coupling-Enabled Alkene Difunctionalization 3.2 Metal-Mediated Radical Transfer Coupling Enabled Alkene Difunctionalization 3.3 Metalloid-Mediated Radical Transfer Coupling Enabled Alkene Difunctionalization 4 Electrochemical Alkene Difunctionalization Terminated by Functionality Migration 5 Summary and Outlook