Native Amide-Directed C(sp3)-H Alkynylation Using an Electron-Deficient Iridium Catalyst with Pyridone Ligand
Shunsuke Kimura1, Tomoaki Kobayashi1, Yuki Hirata1,2
1Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
Abstract:
The direct functionalization of C(sp3)-H bonds assisted by native carbonyl functional groups is a promising strategy for the streamlined synthesis of complex molecules. Here, we report native amide-directed C(sp3)-H alkynylation reactions using an electron-deficient iridium catalyst and an electron-deficient pyridone ligand. Under the optimized conditions, the C(sp3)-H alkynylation of terminal methyl groups and internal methylene groups of cyclobutane carboxamides afforded the desired products in moderate to good yields.
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