Liang Kangjiang, Li Tao, Li Na, Zhang Yang, Shen Lei, Ma Zhixian, Xia Chengfeng
Key Laboratory of Medicinal Chemistry for Natural Resource (Ministry of Education and Yunnan Province), State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, School of Chemical Science and Technology, Library of Yunnan University, Yunnan University 2 North Cuihu Road Kunming 650091 China
Chem Sci. 2020 Jan 10;11(8):2130-2135. doi: 10.1039/c9sc06184c.
Disclosed herein is a photochemical Heck-type arylation of vinylphenols with non-activated aryl and heteroaryl halides under visible light irradiation. Preliminary mechanistic studies suggested that the colored vinylphenolate anions acted as a strong reducing photoactivator to directly activate (hetero)aryl halides without the need for any sacrificial reductants. The photochemically generated aryl radicals coupled with another molecule of vinylphenol to afford the Heck-type arylation product in a regiospecific and stereoselective manner. The developed photochemical arylation protocol showed exceptional functional group tolerance and was successfully applied in the challenging late-stage modification of natural products without any protection-deprotection procedures.
本文公开了在可见光照射下,乙烯基酚与未活化的芳基和杂芳基卤化物进行光化学Heck型芳基化反应。初步机理研究表明,有色的乙烯基酚酸根阴离子作为一种强还原性光活化剂,可直接活化(杂)芳基卤化物,而无需任何牺牲性还原剂。光化学产生的芳基自由基与另一分子乙烯基酚偶联,以区域特异性和立体选择性的方式得到Heck型芳基化产物。所开发的光化学芳基化方法具有出色的官能团耐受性,并成功应用于天然产物具有挑战性的后期修饰,无需任何保护-脱保护步骤。