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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Cobalt(II)-Catalyzed [4+2] Annulation of Picolinamides with Alkynes via C-H Bond Activation
Yongqi Yao1, Qifu Lin1, Wen Yang1
1Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education, School of Chemistry, South China, Normal University, Guangzhou, 510006, P. R. China.
Abstract:
A cobalt(II)-catalyzed [4+2] annulation of picolinamides with alkynes via C-H bond activation has been developed. The operationally simple annulation reaction allows for the synthesis of acyl-substituted 1H-benzoquinoline bearing multiple aromatic rings (up to 96 % yield) without co-oxidant or other oxidation factors under mild conditions. Several control experiments were carried out. This practical [4+2] annulation provides an efficient route to access highly functionalized compounds.
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