TEMPO mediated oxidative annulation of aryl methyl ketones with amines/ammonium acetate for imidazole synthesis
作者:Furong Geng、Shaofeng Wu、Xinyang Gan、Wenjuan Hou、Jianyu Dong、Yongbo Zhou
DOI:10.1039/d2ob00828a
日期:——
A facile synthesis of 1H-imidazoles by direct oxidative annulation of aryl methyl ketones and primary amines has been developed in the presence of TEMPO under weakly acidic conditions. By replacing amines with ammonium acetate, 2H-imidazole skeletons were achieved for the first time from ketones. Substrates containing various functional groups, such as alkyl, aryl, naphthyl, halogen (F, Cl, Br, I)
在弱酸性条件下,在 TEMPO 存在下,通过芳基甲基酮和伯胺的直接氧化环化,开发了一种简便的 1 H-咪唑合成方法。通过用乙酸铵代替胺类,首次从酮类中获得了2 H-咪唑骨架。含有各种官能团的底物,如烷基、芳基、萘基、卤素(F、Cl、Br、I)、硝基、三氟甲基、磺酰基酯、呋喃基、噻吩基和吡啶基,很容易转化为所需的产物。通过咪唑的放大合成和 Sonogashira 偶联功能化验证了该方法的应用潜力。从机理上讲,α-TEMPO-烯胺加合物可以作为关键的反应中间体。