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Updated: Oct 14, 2025

Preparation of N-2-alkoxyvinylsulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines
Published on: January 3, 2018
Synthesis of multi-substituted 1,2,4-triazoles utilising the ambiphilic reactivity of hydrazones
Haruo Matsuzaki1, Norihiko Takeda1, Motohiro Yasui1
1Kobe Pharmaceutical University, Motoyamakita, Higashinada, Kobe 658-8558, Japan. masa-u@kobepharma-u.ac.jp.
Abstract:
The synthesis of N-alkyl-1H-1,2,4-triazoles from N,N-dialkylhydrazones and nitriles via formal [3+2] cycloaddition including the C-chlorination/nucleophilic addition/cyclisation/dealkylation sequence was developed. This sequential reaction utilising the in situ generation of hydrazonoyl chloride based on the ambiphilic reactivity of hydrazones afforded a variety of multi-substituted N-alkyl-triazoles in high yields. The synthetic utility of multi-substituted triazoles was also demonstrated by further transformations.
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