Ni-Catalyzed Reductive Coupling of Alkynes and Amides to Access Multi-Functionalized Indoles
Kwan Hong Min1, Naeem Iqbal1, Eun Jin Cho1
1Department of Chemistry, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, Republic of Korea.
Abstract:
A nickel-catalyzed reductive coupling of alkynes and amides, followed by base-free transmetalation, proceeded selectively in the presence of an uncommon bidentate primary aminophosphine ligand to access highly functionalized indoles comprising biologically important trifluoromethyl groups and challenging electron-rich alkenyl groups at the 2- and 3-positions, respectively. Indole molecules were installed within natural products or drug molecules under mild conditions, and a trifluoromethylated analogue of a drug molecule (pravadoline) was also synthesized.
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