N‐Heterocyclic Carbene/Cobalt Cooperative Catalysis for the Chemo‐ and Regioselective C−N Bond Formation between Aldehyde and Amines/Amides
作者:Asher M. Siddiqui、Anam Khalid、Arif Khan、Chandra S. Azad、Mohd. Samim、Imran A. Khan
DOI:10.1002/cctc.202000156
日期:2020.9.4
examples), tertiaryamides (31 examples), and imides (16 examples) by a Cobalt(II) catalyzed oxidative amide coupling in aqueous media. The Co(III)‐TMC was reacted with N‐Heteroatom Carbene to form active catalyst Co(II)NHC‐TMC in situ which involves in the coordination with Breslow's intermediate and SET for the activation of aldehyde and amides. The mechanism for activation of amide and amine differs
通过钴(II)在水性介质中催化氧化酰胺偶联反应构建各种仲(4个实例),叔酰胺(31个实例)和酰亚胺(16个实例)的新颖方法。Co(III)-TMC与N-Heteroatom Carbene反应形成原位活性催化剂Co(II)NHC-TMC ,该催化剂涉及与Breslow中间体和SET的配位,以活化醛和酰胺。酰胺和胺的活化机理分别基于基于SET的亲核加成和配体交换而不同。使用Fe(III)(EDTA)-H 2 O 2作为氧化剂可实现催化剂的再生。Co(II)TMC‐O 2的使用在该过程中也发现同样有效。发现该方法在存在同样敏感的邻-C-H键活化的情况下对NH活化具有区域选择性。发现胺比相应的酰胺更易受反应影响。
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