Immobilization of copper(I) iodide on polyaza-ligand-functionalized polyacrylonitrile fibers as highly active catalysts for the 1,3-dipolar cycloaddition reaction

Abstract

Copper(I) iodide (CuI) was grafted on oxa- and aza-ligand-functionalized polyacrylonitrile fibers (PANFs) to obtain highly active catalysts for the 1,3-dipolar cycloaddition reaction. The fibers were characterized using techniques such as inductively coupled plasma optical atomic emission spectrometry, Fourier-transform infrared spectroscopy, X-ray diffraction, elemental analysis, and X-ray photoelectron spectroscopy, which collectively confirmed that the functionalized fibers were successfully prepared. The catalytic performances of the prepared fibers in the 1,3-dipolar cycloaddition reaction were evaluated. Among the catalysts prepared, the polyaza-ligand-functionalized PANF-immobilized CuI catalyst (PANPAL-1F–CuI) exhibited the best catalytic activity, achieving a high yield of 99%. Furthermore, PANPAL-1F–CuI was chosen for the synthesis of 1,2,3-triazoles with an extensive scope (32 examples) under mild reaction conditions. PANPAL-1F–CuI could be recycled 8 times with a slight decrease in catalytic activity. Finally, a possible mechanism for the PANPAL-1F–CuI-catalyzed 1,3-dipolar cycloaddition was proposed herein.