文献类型：期刊文献

英文题名：Gold(I) or Gold(III) as Real Intermediate Species in Gold-Catalyzed Cycloaddition Reactions of Enynal/Enynone?

作者：Zhang, Caiyun[1,2];Wang, Gendi[1,2];Zhan, Licheng[1,2];Yang, Xueyan[1,2];Wang, Jiwei[1,2];Wei, Yin[3];Xu, Sheng[1,2];Shi, Min[1,2,3];Zhang, Jun[1,2]

机构：[1]East China Univ Sci & Technol, Sch Chem & Mol Engn, Feringa Nobel Prize Scientist Joint Res Ctr, Key Lab Adv Mat, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Sch Chem & Mol Engn, Feringa Nobel Prize Scientist Joint Res Ctr, Joint Int Res Lab Precis Chem & Mol Engn, Shanghai 200237, Peoples R China;[3]Chinese Acad Sci, State Key Lab Organometall Chem, Shanghai Inst Organ Chem, Shanghai 200032, Peoples R China

年份：2020

卷号：10

期号：12

起止页码：6682

外文期刊名：ACS CATALYSIS

收录：;EI(收录号：20203309033684);WOS:【SCI-EXPANDED(收录号:WOS:000543663800010)】；

基金：Financial support from the National Natural Science Foundation of China for financial support (21671066) is greatly acknowledged.

语种：英文

外文关键词：gold(I) catalysis; gold(III) catalysis; cycloaddition; enynal/enynone; reaction intermediates

摘要：Metal bound isobenzopyrylium species are proposed as reactive intermediates in transition-metal-catalyzed [3 + 2] or [4 + 2] cyclizations of o-alkynylbenzaldehydes (enynals) or o-alkynylarylketones (enynones). Because of their high reactivity, isolation and structural characterization of such intermediates have remained elusive. Herein, we report the isolation of such gold(I)and gold(III)-bound isobenzopyrylium intermediates, and two of them have been characterized by X-ray diffraction analysis. When reacting with reaction partners, such as styrene and phenyl acetylene, the Au(I) intermediate exhibited a reaction rate much faster than that of the Au(III) species. A degradation pathway of active Au(III)-carbene intermediate was observed, leading to release of Au(I) species and consequent formation of a dichloride compound. In other related catalytic reactions, the Au(I) intermediate could react well with a range of cyclization partners, whereas the Au(III) intermediate did not work. The above observations indicate that Au(I) species is probably the real catalyst in such gold-catalyzed transformations of o-alkynylbenzaldehydes and o-alkynylarylketones.