Organophotoredox-mediated Formal [3+2]-Cycloaddition of 2H-Azirines with Aryldiazonium Salts: Direct Access to Trisubstituted 1,2,4-Triazoles

Poornima Mishra; Prashant Kumar; Oj Shikhar Srivastava; Namrata Rastogi

doi:10.1002/asia.202300007

Organophotoredox-mediated Formal [3+2]-Cycloaddition of 2H-Azirines with Aryldiazonium Salts: Direct Access to Trisubstituted 1,2,4-Triazoles

Chem Asian J. 2023 Apr 3;18(7):e202300007. doi: 10.1002/asia.202300007. Epub 2023 Feb 28.

Authors

Poornima Mishra^{1

2}, Prashant Kumar¹, Oj Shikhar Srivastava¹, Namrata Rastogi^{1

2}

Affiliations

¹ Medicinal & Process Chemistry Division, CSIR-Central Drug Research Institute, Sec. 10, Jankipuram Extension, Sitapur Road, P.O. Box 173, Lucknow, 226031, India.
² Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India.

PMID: 36852773
DOI: 10.1002/asia.202300007

Abstract

The present work documents an organophotoredox-mediated formal [3+2]-cycloaddition of 2H-azirines with aryl diazonium tetrafluoroborate salts to furnish 1,3,5-trisubstituted 1,2,4-triazoles. The reaction furnishes a regioisomeric mixture of 1,2,4-triazoles in case of unsymmetrically substituted azirines. It is noteworthy that aryl radical generation from diazonium salt under visible light photoredox conditions could be successfully avoided by carefully selecting the reaction conditions.

Keywords: 1,2,4-triazoles; 2H-azirines Organophotocatalytic; aryldiazonium salts; cycloaddition.

Abstract

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