武汉大学郭勉团队近日研究了非血红素铁配合物催化烯烃的光诱导硫氰酸化的合成方法和机理见解。相关论文于2025年6月17日发表在《中国化学》杂志上。

众所周知，高价铁配合物Fe-X会将其X基团转移到碳自由基物种上，形成R-X键。为了利用铁催化剂的这种能力，在自由基引发剂的存在下，研究组开发了一种新型的光诱导铁催化体系，用于烯烃的双官能化。然而，反应机理的细节尚不清楚，特别是催化翻转过程中光催化剂和铁催化剂的转变。 

研究组扩展了光驱动的非血红素铁配合物催化苯乙烯底物硫氰酸根反应。该方案显示出广泛的底物范围和高效率。使用各种光谱学（如紫外-可见光谱、质谱、瞬态吸收光谱和X射线吸收光谱）进行的详细机理研究揭示了光催化剂[IrIII（ppy）₃]和基团转移催化剂[FeII（bpmen）]²⁺的转变。实时光谱结合机理实验表明，[IrIV（ppy）₃]⁺和[FeIII（bpmen）]³⁺是反应循环中涉及的关键中间体。

附：英文原文

Title: Photo-induced Thiocyanation of Alkenes Catalyzed by Non-heme Iron Complexes: Synthetic Methodology and Mechanistic Insights

Author: Cece Wang, Yingji Liu, Haozhe Dong, Mian Guo

Issue&Volume: 2025-06-17

Abstract: High valent iron complexes Fe-X have been known to transfer their X group toward carbon radical species to form R–X bond. To utilize this capability of iron catalyst, novel photo-induced iron catalysis system had been developed in the difunctionalization of alkenes in the presence of radical initiator. However, the details of the reaction mechanism are still unclear, especially the transformations of the photocatalyst and the iron catalyst during the catalytic turnover. Herein, we expanded the photo-driven non-heme iron complex catalyzed thiocyanation of styrene substrate. This protocol exhibited broad substrate scope and high efficiency. Detailed mechanistic studies using various spectroscopies, such as UV-vis, mass spectrometry, transient absorption spectroscopy and X-ray absorption spectroscopy, revealed the transformations of photocatalyst [IrIII(ppy)3] and group transfer catalyst [FeII(bpmen)]2+. Real-time spectroscopies combined with mechanistic experiments demonstrated that [IrIV(ppy)3]+ and [FeIII(bpmen)]3+ were the key intermediates involved in the reaction cycle.

DOI: 10.1002/cjoc.70133

Source: https://onlinelibrary.wiley.com/doi/10.1002/cjoc.70133