Selective silver (I)-catalyzed four-component gram-scale synthesis of novel 1,4-disubstituted 1,2,3-triazole-sulfonamides under heterogeneous catalysis and microwave irradiation in water

Abstract

The Ag3PO4-MEA catalyst was successfully prepared and proved to be an efficient and selective catalyst of the multicomponent synthesis of a new library of 1,4-disubstituted 1,2,3-triazole-sulfonamides 5a-n. This new methodology cleanly proceeded in water under microwave activation using N-propargyl saccharin, NaN3 or SO2(N3)2, substituted benzyl chloride or protected sugar and non-conjugated primary amines, using Ag(I) in a method-comparison study to Cu(I) as conventional Sharpless catalyst. The proposed strategy allows a simple, rapid and scalable route to 1,2,3-triazoles sulfonamides derivatives 5 through in-situ ring-opening of saccharin system with primary amine. All compounds have been fully characterized by NMR, mass spectrometry and X-ray crystallography analysis. The catalyst has been prepared via a green Sol-Gel methodology and fully analyzed by X-ray Diffraction (XRD), Fourier Transform Infrared (FTIR) Spectroscopy and Scanning Electron Microscopy (SEM) coupled to Energy Dispersive X-ray Spectroscopy (EDX), and Brunauer-Emmett-Teller (BET) method. The catalyst is easily recovered during the process and showed high recyclability.