Chatterjee Souvik, Azmi Sabnam, Bandopadhyay Nilaj, Paramanik Krishnendu, Sarkar Gayetri, Biswas Bhaskar, Das Hari Sankar
Department of Chemistry, University of North Bengal, Darjeeling 734013, India.
Org Biomol Chem. 2024 Nov 27;22(46):9072-9077. doi: 10.1039/d4ob01377h.
Carbon-halogen bond cleavage in aryl halides through single electron transfer (SET) is a crucial step in radical-based cross-coupling reactions. Accomplishing such cleavage using an organic system without the assistance of any transition metal-based catalyst is highly challenging. In recent years, combining organic molecules and a base has served as a unique system for SET-mediated carbon-halogen bond cleavage. Herein, we report the combination of simple benzylamine and potassium -butoxide as a super-electron-donor system for SET-mediated cleavage of aryl halides generating reactive aryl radicals, which subsequently react with arenes or heteroarenes and produce biaryl skeletons. The new methodology enables the arylation of arenes and heteroarenes with aryl iodides, or aryl bromides, upon excitation with heat or light. The broad substrate scope, mild reaction conditions and tolerance of common organic functional groups offer an efficient alternative route for direct C-H arylation reactions.
通过单电子转移(SET)实现芳基卤化物中碳-卤键的裂解是基于自由基的交叉偶联反应中的关键步骤。在没有任何过渡金属基催化剂辅助的情况下,使用有机体系完成这种裂解极具挑战性。近年来,将有机分子与碱相结合已成为SET介导的碳-卤键裂解的独特体系。在此,我们报道了简单的苄胺与叔丁醇钾的组合作为一种超电子供体体系,用于SET介导的芳基卤化物裂解以生成活性芳基自由基,这些自由基随后与芳烃或杂芳烃反应并生成联芳基骨架。这种新方法能够在加热或光照激发下,实现芳烃和杂芳烃与芳基碘化物或芳基溴化物的芳基化反应。广泛的底物范围、温和的反应条件以及对常见有机官能团的耐受性为直接C-H芳基化反应提供了一条有效的替代途径。