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Updated: May 26, 2026

Preparation of N-(2-alkoxyvinyl)sulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines
Published on: January 3, 2018
Gold-catalyzed three-component annulation: efficient synthesis of highly functionalized dihydropyrazoles from
Yamato Suzuki1, Saori Naoe, Shinya Oishi
1Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan.
Abstract:
Polysubstituted dihydropyrazoles were directly obtained by a gold-catalyzed three-component annulation. This reaction consists of a Mannich-type coupling of alkynes with N,N'-disubstituted hydrazines and aldehydes/ketones followed by intramolecular hydroamination. Cascade cyclization using 1,2-dialkynylbenzene derivatives as the alkyne component was also performed producing fused tricyclic dihydropyrazoles in good yields.
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