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Updated: Jul 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
Pyrrolidine/Azepane Ring Expansion via Intramolecular Ullmann-Type Annulation/Rearrangement Cascade: Synthesis of
Polina M Ivantcova1, Anna A Kirsanova2, Vladimir I Polshakov3
1Sirius University of Science and Technology, Olympic Ave 1, 354340 Sochi, Russian Federation.
Abstract:
5-Arylpyrrolidine-2-carboxylates with an ortho-halogen substituent at 5-aryl and an electron-withdrawing group at the C4 position of the pyrrolidine ring were transformed into 1H-benzo[b]azepine-2-carboxylates under Cu(I) promotion and microwave activation. Reaction promoter copper(I) thiophene-2-carboxylate has been generated in situ in the reaction's environment from Cu2O and thiophene-2-carboxylic acid. Functionalized 1H-benzo[b]azepine-2-carboxylates were obtained in racemic and optically active forms in 67-89% yields. Subsequent stereoselective 1,3-dipolar cycloaddition and an Ullmann-type annulation/rearrangement cascade (UARC) ensure a synthetic route to oligomeric optically active benzazepine species with a well-defined 3D-structure.
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