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Updated: May 15, 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
Silver(I) triflate-catalyzed post-Ugi synthesis of pyrazolodiazepines
Muhammad Hasan1, Anatoly A Peshkov2, Syed Anis Ali Shah1
1College of Chemistry Chemical Engineering and Material Science, Soochow University, Suzhou, 215123, P.R. China.
Abstract:
A silver(I) triflate-catalyzed post-Ugi assembly of novel pyrazolo[1,5-a][1,4]diazepine scaffolds is reported offering high yields (up to 98%) under mild conditions. The synthetic sequence involves the Ugi four-component reaction (U4CR) of pyrazole-3-carbaldehydes, primary amines, 3-substituted propiolic acids, and isocyanides, followed by a silver(I) triflate-catalyzed intramolecular heteroannulation of the resulting pyrazole-tethered propargylamides occurring in a 7-endo-dig fashion. The approach is scalable and tolerates a diverse range of substitution patterns.
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