Wang Zhonghe, Zeng Le, He Cheng, Duan Chunying
State Key Laboratory of Fine Chemicals, Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian 116024, China.
ACS Appl Mater Interfaces. 2021 Jun 9;13(22):25898-25905. doi: 10.1021/acsami.1c03098. Epub 2021 May 27.
Hydrogen atom transfer (HAT) has become an attractive strategy for the activation of hydrocarbon feedstocks. Alcohols, as inexpensive and efficient hydrogen transfer reagents, have limited application in C-H functionalization due to the difficulty in the alkoxy radical acquisition. 9-Fluorenone moieties were incorporated into the metal-organic framework (MOF) as a photocatalyst; through the formation of hydrogen bonds between the carbonyl group of a ligand and alcohol, alkoxy radicals could be obtained by the visible-light-driven oxidation of 2,2,2-trichloroethanol proton-coupled electron transfer (PCET). Effectively photocatalyzed intermolecular coupling reactions between phenyl vinyl sulfone and aldehyde or cyclic ether were realized through the HAT pathway. Compared to homogeneous catalysts, the heterogeneous MOF photocatalyst improved the catalytic efficiency and could be recycled at least five times. The microenvironment of the Zn-OFDC channel was beneficial for the formation of hydrogen bonds and stability of alkoxy radicals.
氢原子转移（HAT）已成为一种用于活化烃类原料的有吸引力的策略。醇类作为廉价且高效的氢转移试剂，由于获取烷氧基自由基存在困难，在C-H官能化中的应用有限。9-芴酮部分被引入金属有机框架（MOF）作为光催化剂；通过配体的羰基与醇之间形成氢键，可通过2,2,2-三氯乙醇的可见光驱动氧化的质子耦合电子转移（PCET）获得烷氧基自由基。通过HAT途径有效地实现了苯乙烯基砜与醛或环醚之间的光催化分子间偶联反应。与均相催化剂相比，非均相MOF光催化剂提高了催化效率，并且可以至少循环使用五次。Zn-OFDC通道的微环境有利于氢键的形成和烷氧基自由基的稳定性。
