School of Metallurgical and Chemical Engineering, Jiangxi University of Science and Technology, 86 Hongqi Road, Ganzhou 341000, China.
Org Biomol Chem. 2019 Apr 24;17(17):4335-4341. doi: 10.1039/c9ob00320g.
A TBAB-catalyzed oxidative 6-endo-dig oxy-cyclization of 2-alkynylbenzamide is described herein for the synthesis of isocoumarin-1-imines. The transformation proceeds regioselectively and provides the final products with high efficiency and a broad reaction scope. Interestingly, an array of isobenzofuran-1-imines is also achieved under standard conditions when N-phenyl 2-trimethylsilylethynylbenzamides are used as substrates. Mechanism studies show that 3-bromomethenisobenzofuran-1-imine is a pivotal intermediate, which goes through C-O bond migration and debromination to offer the final isocoumarin-1-imines.
本文描述了一种 TBAB 催化的 2-炔基苯甲酰胺的氧化 6-endo-内型环氧化反应，用于合成异香豆素-1-亚胺。该转化具有区域选择性，以高效率和广泛的反应范围提供最终产物。有趣的是，当使用 N-苯基 2-三甲基甲硅烷基乙炔基苯甲酰胺作为底物时，在标准条件下也可以获得一系列异苯并呋喃-1-亚胺。机理研究表明，3-溴亚甲异苯并呋喃-1-亚胺是一个关键中间体，它经历 C-O 键迁移和脱溴化作用生成最终的异香豆素-1-亚胺。
