Enzyme-Inspired Coordination Polymers for Selective Oxidization of C(sp 3 )–H Bonds via Multiphoton Excitation

作者：Hui‐Lin Huang, Xu Jing, Jiangtao Deng, Changgong Meng, Chunying Duan · 发表于：Journal of the American Chemical Society · 年份：2023 · DOI：10.1021/jacs.2c09348 · 被引用次数：64 · 研究领域：Metal-Catalyzed Oxygenation Mechanisms、Catalytic C–H Functionalization Methods、Oxidative Organic Chemistry Reactions

Nature’s blueprint provides the fundamental principles for expanding the use of abundant metals in catalysis; however, mimicking both the structure and function of copper enzymes simultaneously in one artificial system for selective C–H bond oxidation faces marked challenges. Herein, we report a new approach to the assembly of artificial monooxygenases utilizing a binuclear Cu 2 S 2 Cl 2 cluster to duplicate the identical structure and catalysis of the Cu A enzyme. The designed monooxygenase Cu-Cl-bpyc facilitates well-defined redox potential that initially activated O 2 via photoinduced electron transfer, and generated an active chlorine radical via a ligand-to-metal charge transfer (LMCT) process from the consecutive excitation of the in situ formed copper(II) center. The chlorine radical abstracts a hydrogen atom selectively from C(sp 3 )–H bonds to generate the radical intermediate; meanwhile, the O 2 •– species interacted with the mimic to form mixed-valence species, giving the desired oxidization products with inherent product selectivity of copper monooxygenases and recovering the catalyst directly. This enzymatic protocol exhibits excellent recyclability, good functional group tolerance, and broad substrate scope, including some biological and pharmacologically relevant targets. Mechanistic studies indicate that the C–H bond cleavage was the rate-determining step and the cuprous interactions were essential to stabilize the active oxygen species. The well-defined struc...