Spin effect on redox acceleration and regioselectivity in Fe-catalyzed alkyne hydrosilylation  

作　　者：Peng He Meng-Yang Hu Jin-Hong Li Tian-Zhang Qiao Yi-Lin Lu Shou-Fei Zhu 

机构地区：[1]Frontiers Science Center for New Organic Matter,State Key Laboratory and Institute of Elemento-Organic Chemistry,Nankai University,Tianjin 300071,China

出　　处：《National Science Review》2024年第2期150-162,共13页国家科学评论（英文版）

基　　金：supported by the National Key R&D Program of China (2021YFA1500200);National Natural Science Foundation of China (22001129, 92256301, 92156006, 21971119 and 22221002);Program of Introducing Talents of Discipline to Universities (‘111’ project, B06005) of the Ministry of Education of China;Haihe Laboratory of Sustainable Chemical Transformations;Fundamental Research Funds for the Central Universities;New Cornerstone Science Foundation through XPLORER PRIZE

摘　　要：Iron catalysts are ideal transition metal catalysts because of the Earths abundant,cheap,biocompatible features of iron salts.Iron catalysts often have unique open-shell structures that easily undergo spin crossover in chemical transformations,a feature rarely found in noble metal catalysts.Unfortunately,little is known currently about how the open-shell structure and spin crossover affect the reactivity and selectivity of iron catalysts,which makes the development of iron catalysts a low efficient trial-and-error program.In this paper,a combination of experiments and theoretical calculations revealed that the iron-catalyzed hydrosilylation of alkynes is typical spin-crossover catalysis.Deep insight into the electronic structures of a set of well-defined open-shell active formal Fe(0)catalysts revealed that the spin-delocalization between the iron center and the 1,10-phenanthroline ligand effectively regulates the iron center’s spin and oxidation state to meet the opposite electrostatic requirements of oxidative addition and reductive elimination,respectively,and the spin crossover is essential for this electron transfer process.The triplet transition state was essential for achieving high regioselectivity through tuning the nonbonding interactions.These findings provide an important reference for understanding the effect of catalyst spin state on reaction.It is inspiring for the development of iron catalysts and other Earth-abundant metal catalysts,especially from the point of view of ligand development.

关 键 词：spin effect spin-delocalization spin crossover iron-catalysis alkyne hydrosilylation 

分 类 号：TQ426[化学工程]