基于钴催化吲哚酰胺与二炔和单炔的[4+2]环化反应合成γ-咔啉酮  

Cobalt-Catalyzed [4+2] Annulation of Indole Carboxamide with Diynes and Monoacetylene: Direct Access to γ-Carbolinones

作　　者：贝文峰 潘健 冉冬梅 刘伊琳 杨震 冯若昆 Bei Wenfeng;Pan Jian;Ran Dongmei;Liu Yilin;Yang Zhen;Feng Ruokun(Zhejiang Key Laboratory of Alternative Technologies for Fine Chemicals Process,College of Chemistry and Chemical Engineering,Shaoxing University,Shaoxing,Zhejiang 312000)

机构地区：[1]绍兴文理学院化学化工学院、浙江省精细化学品传统工艺替代技术研究重点实验室,浙江绍兴312000

出　　处：《有机化学》2023年第9期3226-3238,共13页Chinese Journal of Organic Chemistry

基　　金：浙江省自然科学基金(LQ15B020002);绍兴市科技计划(2018C10017);国家级大学生创新创业训练计划(202110349018);国家级大学生创新创业训练计划(202210349010);浙江省教育厅科研计划(Y202043097)。

摘　　要：采用廉价易得的过渡金属钴盐为催化剂, 实现了3-吲哚甲酰胺与炔烃的C—H/N—H活化环化反应, 制备了一系列γ-咔啉酮类化合物. 实验表明反应的最佳条件为: 10 mol%乙酰丙酮钴为催化剂, 1.0 equiv.乙酰丙酮锰为氧化剂, 2.0 equiv.特戊酸钠为碱, 三氟乙醇为溶剂, 120 ℃搅拌24 h. 该方法具有良好的底物适用性, 各种芳基或烷基取代的1,3-丁二炔均可以在标准条件下与3-吲哚甲酰胺反应, 并以中等到良好的收率得到3-炔基取代的γ-咔啉酮类化合物. 此外, 当使用端炔和内炔作为环化试剂时, 反应也可以以较好的产率和较高的选择性得到目标产物. 该反应使用廉价金属钴和锰为催化体系, 不需要额外配体和吲哚氮保护基团, 为合成具有广泛应用价值的γ-咔啉酮类化合物提供了一种有机合成方法.A cobalt-catalyzed annulation of the C(sp2)—H/N—H bond of 3-indolecarboxamides with alkynes assisted by 8-aminoquinoline is reported for the preparation of γ-carbolinones. The research results indicated that under the optimal reaction conditions, the isolated yield was up to 90% with Co(acac)2 (10 mol%) as catalyst, Mn(acac)3 (1.0 equiv.) as oxidant, NaOPiv (2.0 equiv.) as base, trifluoroethanol (2.0 mL) as solvent at 120 ℃ for 24 h. The protocol has a broad scope for alkynes. Both 1,4-diarylbuta-1,3-diynes and dialkyl diynes could react with N-(quinolin-8-yl)-1H-indole-3-carboxamide, giving the desired products in moderate to good yield. It was noteworthy that terminal and internal alkynes were found to be applicable to this transformation, affording the γ-carbolinones in good yield and high selectivity. This method has the advantages of applying cheap and commercially available cobalt and manganese salts as the catalytic system, requiring no additional ligands and indole nitrogen protecting groups, providing a new method for the synthesis of γ-carbolinone compounds with wide application value.

关 键 词：钴催化 吲哚甲酰胺 炔烃 [4+2]环化 γ-咔啉酮 

分 类 号：O626[理学—有机化学]