乌普萨拉大学Leif Hammarstrom教授课题组在2021年1月6日出版的《美国化学会志》上发表综述，介绍了质子耦合电子转移反应（PCET）的研究进展。

质子耦合电子转移反应是自然界和人工系统中基础的能量转移反应，其在诸如催化和合成化学等领域中的地位愈发重要。质子和电子转移之间的相互依赖使得这一类反应机理非常丰富，包括各种串联和协同机理。区分不同的PCET机理以及了解为何某一机理占主导地位对于设计和优化运用PCET的反应至关重要。该综述为如何通过解读热力学和温度、压强、同位素依赖的动力学数据，从而区分串联和协同机理提供了一个实用化的指导。

在该文中，研究人员还提出了一个新的PCET分区示意图，以展示怎样通过改变热力学条件（ΔG_PT° and ΔG_ET°）和PCET系统的耦合强度来切换或消除某一种反应机理。此外，研究人员还讨论了以协同但非同步的PCET机理来理解有机反应现象的合理性，以及氢原子转移和其他协同PCET反应之间的区别。

最后，研究人员还展望了PCET研究目前的课题和未来的方向。

附：英文原文

Title: Proton-Coupled Electron Transfer Guidelines, Fair and Square

Author: Robin Tyburski, Tianfei Liu, Starla D. Glover, Leif Hammarstrm

Issue&Volume: January 6, 2021

Abstract: Proton-coupled electron transfer (PCET) reactions are fundamental to energy transformation reactions in natural and artificial systems and are increasingly recognized in areas such as catalysis and synthetic chemistry. The interdependence of proton and electron transfer brings a mechanistic richness of reactivity, including various sequential and concerted mechanisms. Delineating between different PCET mechanisms and understanding why a particular mechanism dominates are crucial for the design and optimization of reactions that use PCET. This Perspective provides practical guidelines for how to discern between sequential and concerted mechanisms based on interpretations of thermodynamic data with temperature-, pressure-, and isotope-dependent kinetics. We present new PCET-zone diagrams that show how a mechanism can switch or even be eliminated by varying the thermodynamic (ΔGPT° and ΔGET°) and coupling strengths for a PCET system. We discuss the appropriateness of asynchronous concerted PCET to rationalize observations in organic reactions, and the distinction between hydrogen atom transfer and other concerted PCET reactions. Contemporary issues and future prospects in PCET research are discussed.

DOI: 10.1021/jacs.0c09106

Source: https://pubs.acs.org/doi/10.1021/jacs.0c09106