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Published on: June 10, 2021
Diazo Activation with Diazonium Salts: Synthesis of Indazole and 1,2,4-Triazole
Xuming Li1, Xiaohan Ye1, Chiyu Wei1
1The Department of Chemistry, University of South Florida, 4202 East Fowler Avenue, Tampa, Florida 33620, United States.
Abstract:
A donor/acceptor diazo activation strategy, processing via condensation using diazonium salts without the addition of any other catalysts or reagents, is reported. The diazenium intermediate was found to undergo cyclization to give indazoles in excellent yields. Alternatively, in the presence of nitriles, substituted 1,2,4-triazoles were obtained in good to excellent yields. This interesting diazenium route provides a new approach to achieve complex heterocycle synthesis under mild conditions.
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