Green Oxidation of Indoles Using Molecular Oxygen over a Copper Nitride Nanocube Catalyst. Issue 30 (8th August 2022)

• Record Type: Journal Article
• Authors: Xu, Hang; Yamaguchi, Sho; Mitsudome, Takato; Mizugaki, Tomoo
• Is Part Of: European journal of organic chemistry. Volume 2022:Issue 30(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-08-08
• Subjects: Indoles -- Molecular oxygen -- Nanocube -- Trimerization -- Witkop oxidation; Chemistry, Organic -- Periodicals; Organic compounds -- Synthesis -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1002/ejoc.202200826
• Languages: English
• ISSNs: 1434-193X

Abstract

Abstract: Oxidative transformation of indoles is a promising approach for synthesizing valuable nitrogen‐containing compounds; however, conventional methods use toxic oxidants and additives. Herein, we report for the first time the catalytic oxidative trimerization and the oxygenative cleavage (Witkop oxidation) of indoles using molecular oxygen under additive‐free conditions accomplished by a copper nitride nanocube (Cu3 N NC) catalyst. The Cu3 N NC catalyst exhibits excellent activity to produce various indolin‐3‐ones and 2‐ketoanilides with high functional group tolerance. Owing to this excellent catalytic performance, the Cu3 N NC catalyst is distinguished from the conventional copper catalysts, demonstrating the high catalytic potential of metal nitride in organic synthesis. Abstract : A green, sustainable, and highly efficient method for the oxidative transformation of indoles was established over a copper nitride nanocube (Cu3 N NC) catalyst. This is the first report on the additive‐free trimerization and Witkop oxidation of indoles using molecular oxygen, which will greatly contribute to the oxidative functionalization of indoles in academic and practical aspect.