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Ultrasound-assisted bromination of indazoles at the C3 position with dibromohydantoin† † Electronic supplementary information (ESI) available. See DOI: https://doi.org/10.1039/d2ra06867b

ABSTRACT: Bromoaryl compounds have attracted great attention in organic chemistry, especially for the synthesis of pharmaceutical intermediates. Herein, we demonstrated a novel and efficient bromination protocol of indazoles via C–H bond cleavage to give site-specific 3-bromide products that could be further employed as synthetic blocks to prepare drugs. The reaction used DBDMH as a bromine source, tolerated a wide range of indazoles, and finished in 30 min under mild, ultrasound-assisted conditions. Besides, preliminary mechanistic studies revealed that this approach was not a radical process. Bromoaryl compounds have attracted great attention in organic chemistry, especially for the synthesis of pharmaceutical intermediates.

SUBMITTER: Ying S

PROVIDER: S-EPMC9773018 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature

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