Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry & Molecular Engineering, East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, P. R. China.
Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, P. R. China.
Chemistry. 2022 Mar 1;28(13):e202103306. doi: 10.1002/chem.202103306. Epub 2022 Feb 9.
Coinage metal-promoted 5-exo and 6-endo selective cyclization of 2-(1-alkynyl)benzaldimines has been studied. It was found that, under gold catalysis, 2-(1-alkynyl)benzaldimines exclusively underwent 5-exo-dig cyclization processes, followed by oxidation to form N-aryl 3-methyleneisoindolin-1-ones. In contrast, in the presence of base and under activation of AgOTf, switching of 5-exo to 6-endo cyclizations of 2-(1-alkynyl)benzaldimines was observed, exclusively giving N-aryl or N-alkyl substituted isoquinolinium salts. The two key reaction intermediates, exocyclic vinyl-Au and the endocyclic vinyl-Ag species have been isolated and characterized, and a study of their reactivities confirms the plausible mechanisms. Reactions of the resultant 3-methyleneisoindolin-1-ones with benzyne afforded structurally important isoindolinone-based benzocyclobutenes. Additionally, several interesting transformations of the resultant isoquinolinium salts have been investigated.
已研究了硬币金属促进的 2-(1-炔基)苯亚胺的 5-endo 和 6-exo 选择性环化反应。研究发现，在金催化下，2-(1-炔基)苯亚胺仅经历 5-exo-内型环化过程，随后氧化形成 N-芳基 3-亚甲基异吲哚-1-酮。相比之下，在碱的存在下并在 AgOTf 的活化下，观察到 2-(1-炔基)苯亚胺的 5-exo 到 6-endo 环化的转换，仅得到 N-芳基或 N-烷基取代的异喹啉鎓盐。已分离和表征了两个关键反应中间体，即外消旋乙烯基-Au 和内消旋乙烯基-Ag 物种，并对它们的反应性进行了研究，证实了合理的机理。所得的 3-亚甲基异吲哚-1-酮与苯炔的反应得到了结构重要的基于异吲哚酮的苯并环丁烯。此外，还研究了所得异喹啉鎓盐的几种有趣的转化。
