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Visible-Light Photocatalytic Functionalization of Isocyanides for the Synthesis of Secondary Amides and Ketene Aminals.

ABSTRACT: A new visible light-induced photocatalytic protocol enabling the formation of secondary amides from electron-poor organic bromides and isocyanides was developed. In addition, the in situ interception of ketenimine intermediates with nitrogen nucleophiles such as amines, hydrazines, and TMSN₃ afforded, in a one-pot two-step procedure, valuable scaffolds such as ketene aminals, pyrazolones, and tetrazoles. Mechanistic evidence confirmed a radical pathway where isocyanides acted as radical geminal acceptors generating key imidoyl radical species.

SUBMITTER: Cannalire R

PROVIDER: S-EPMC8015228 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Visible-Light Photocatalytic Functionalization of Isocyanides for the Synthesis of Secondary Amides and Ketene Aminals.

Cannalire Rolando R Amato Jussara J Summa Vincenzo V Novellino Ettore E Tron Gian Cesare GC Giustiniano Mariateresa M

The Journal of organic chemistry 20201019 21

A new visible light-induced photocatalytic protocol enabling the formation of secondary amides from electron-poor organic bromides and isocyanides was developed. In addition, the in situ interception of ketenimine intermediates with nitrogen nucleophiles such as amines, hydrazines, and TMSN3 afforded, in a one-pot two-step procedure, valuable scaffolds such as ketene aminals, pyrazolones, and tetrazoles. Mechanistic evidence confirmed a radical pathway where isocyanides acted as radic ...[more]

PMID: 33074674

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