Chinese Journal of Organic Chemistry ›› 2021, Vol. 41 ›› Issue (10): 3844-3879.DOI: 10.6023/cjoc202106001 Previous Articles     Next Articles



周子杰a, 孔祥梅a, 刘天飞a,b,*()   

  1. a 南开大学元素有机化学国家重点实验室 天津 300071
    b 中国科学院上海有机化学研究所有机氟化学重点实验室 上海 200032
  • 收稿日期:2021-06-01 修回日期:2021-07-22 发布日期:2021-08-24
  • 通讯作者: 刘天飞
  • 基金资助:

Applications of Proton-Coupled Electron Transfer in Organic Synthesis

Zijie Zhoua, Xiangmei Konga, Tianfei Liua,b()   

  1. a State Key Laboratory of Elemento-organic Chemistry, Nankai University, Tianjin 300071
    b Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032
  • Received:2021-06-01 Revised:2021-07-22 Published:2021-08-24
  • Contact: Tianfei Liu
  • Supported by:
    Startup Fund from Nankai University

Proton-coupled electron transfer (PCET) reactions are a kind of unconventional redox reactions, which exhibit special reactivities and selectivities due to their unique interdependent electron-proton transfer mechanisms. There are three possible pathways of PCET processes, including stepwise electron transfer followed by proton transfer (ETPT), proton transfer followed by electron transfer (PTET), and concerted pathway in which electron and proton transfer synchronously (CEPT), avoiding intermediates with high energy. These reactions have been playing a key role in numerous areas in organic chemistry, inorganic chemistry, bioorganic chemistry, organometallic and material chemistry, including the redox processes in natural and artificial systems, such as the activation for small molecules. Recently, the application of PCET reactions in organic synthesis has received a great deal of attentions and interests. Being accompanied by the development of electrochemical methods and photocatalysts, more and more novel reactions in electrochemistry and photochemistry involve PCET processes have been reported. Applying these electrochemical and photochemical methods, the activation of X—H bond has been achieved via PCET processes, including C—H bond, N—H bond, P—H bond, S—H bond or O—H bond. Thus, based on these crucial processes, a number of vital structures and fundamental frameworks can be synthesized, and various synthetic building blocks and natural products have been attained. For example, pharmaceutical building blocks like 2°-piperidines can be cyanated at their α-position; substituted dimeric pyrroloindolines such as (–)-calycanthidine, (–)-chimonanthine, and (–)-psychotriasine have also been successfully synthesized via PCET mechanism. Moreover, not only the products of reduction of multiple bonds (C=Y bond such as C=C bond, C=N bond and C=O bond), but also the products of self/cross-coupling have been achieved via PCET mechanism. In this review, the recent applications and developments of PCET mechanism in organic synthesis are summarized, including new catalyst systems and new reagents, especially with electrochemical and photochemical methodologies. The future of this area has also been demonstrated from both experimental and theoretical aspects.

Key words: proton-coupled electron transfer, organic synthesis, radical reactions, functionalization