Synthesis and Characterization of a New Nano Ionic Liquid Based on Dawson-Type Polyoxometalate and Its Application in the Synthesis of Symmetrical N,N′-Alkylidene Bisamides

Abstract

A new organic-inorganic nano hybrid ionic liquid based on polyoxometalate H2 [MIMBS]4 [P2W18O62]·11 H2O (MIMBS − P2W18), originated from self-assembling of Dawson-type polyoxometalate [P2W18 O62]6− and organic ionic liquid [1-(3-sulfonic group) butyl-3-methyl imidazolium (MIMBS)] components, has been successfully prepared and characterized by elemental analysis, Fourier transform infrared (FT-IR), 1H, 13C, and 15P nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA), powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The analysis results present that the size range of the nanosheets are between 40 and 50 nm. The resulting heterogeneous catalyst is shown to be an efficient acidic catalyst for the synthesis of symmetrical N, N′-alkylidene bisamides under solvent-free conditions at 80 °C in high yields. After completion of reaction, the catalyst was simply recovered by filtration and recycled without significant loss in the catalytic activity. The hallmark privileges presented by this method are green chemistry, mild condition, simple method and great yield.