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Updated: Jun 8, 2025
![[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)
[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
Photocatalytic One-Pot Three-Component Reaction for the Regioselective Synthesis of Bromo-Substituted Pyrazoles
Zhiying Zhang1, Yinyin Li1, Yatang Wang1
1Jiangxi Provincial Key Laboratory of Synthetic Pharmaceutical Chemistry, Gannan Normal University, Ganzhou 341000, China.
Abstract:
A photocatalytic three-component cascade reaction of readily available enaminones, hydrazines, and CBr4 for the synthesis of bromo-substituted pyrazoles in one pot has been demonstrated. This strategy involves intermolecular C-N/C-Br bond formation and represents an efficient approach to the construction of 4-bromo-substituted pyrazoles with high regioselectivity, broad substrate scope, good functional group tolerance, convenient operation, and mild reaction conditions. Mechanistic investigations show that this reaction proceeds via intermolecular cyclization of enaminones with hydrazines, followed by a regioselective bromination of pyrazoles using CBr4 as a "Br" source.
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