Ru(II)-Catalyzed Skeletal Editing of Oxindole with Internal Alkyne To Synthesize C7-Alkylated Indole Derivatives
Sarbojit Das1, Raktim Saha1, Souvik Bhadra1
1Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302, India.
Abstract:
A Ru(II)-catalyzed skeletal editing of oxindole scaffolds was established to afford C7-alkyl acetate indole derivatives using internal alkyne and alkyl alcohol. The developed method is simple, efficient, and straightforward. The reaction was extended to substrates having wide chemoselective profiles. When unsymmetrical alkynes were used, promising regioselectivity was realized. A preliminary mechanistic study revealed that the reaction pathway proceeded by Ru(II)/Ag(I)-catalyzed amide cleavage and subsequent oxidative annulation.
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