Zhao Xiu, Bai Leiyang, Li Jiayi, Jiang Xuefeng
Hainan Institute of East China Normal University, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, State Key Laboratory of Petroleum Molecular & Process Engineering, School of Chemistry and Molecular Engineering, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, P.R. China.
State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, P.R. China.
J Am Chem Soc. 2024 Apr 9. doi: 10.1021/jacs.3c13908.
The C-F bond is the strongest covalent single bond (126 kcal/mol) in carbon-centered bonds, in which the highest electronegativity of fluorine (χ = 4) gives rise to the shortest bond length (1.38 Å) and the smallest van der Waals radius ( = 1.47 Å), resulting in enormous challenges for activation and transformation. Herein, C-F conversion was realized via photouranium-catalyzed hydroxylation of unactivated aryl fluorides using water as a hydroxyl source to deliver multifunctional phenols under ambient conditions. The activation featured cascade sequences of single electron transfer (SET)/hydrogen atom transfer (HAT)/oxygen atom transfer (OAT), highly integrated from the excited uranyl cation. The *UO prompted water splitting under mild photoexcitation, caging the active oxygen in a peroxo-bridged manner for the critical OAT process and releasing hydrogen via the HAT process.
碳氟键是碳中心键中最强的共价单键（126千卡/摩尔），其中氟的电负性最高（χ = 4），导致键长最短（1.38 Å）和范德华半径最小（ = 1.47 Å），这给活化和转化带来了巨大挑战。在此，通过光铀催化未活化芳基氟化物的羟基化反应实现了碳氟转化，使用水作为羟基源在环境条件下生成多功能酚。该活化过程具有单电子转移（SET）/氢原子转移（HAT）/氧原子转移（OAT）的级联序列，由激发态的铀酰阳离子高度整合而成。*UO在温和的光激发下促使水分解，以过氧桥连的方式捕获活性氧用于关键的OAT过程，并通过HAT过程释放氢。
