Clicked graphene oxide supported venturello catalyst: A new hybrid nanomaterial as catalyst for the selective epoxidation of olefins

Abstract

A new peroxopolyoxotungstate-graphene oxide hybrid nanomaterial was developed by means of click chemistry approach. Graphene oxide (GO) was modified by cysteamine hydrochloride as linking agent via thiol-ene click reaction. Then, Venturello anion, {PO4·[WO2(O2)2]4}3-, was supported on the surface of clicked graphene oxide through the electrostatic interaction with ammonium groups. The prepared material was characterized by Fourier transform infrared (FT-IR) and inductively coupled plasma-optical emission spectroscopies (ICP-OES), X-ray diffraction (XRD), N2 adsorption–desorption analysis, transmission electron microscopy (TEM), and thermogravimetric (TGA-DTA) analyses. ICP-OES analysis showed 0.041 mmol g−1 of peroxopolyoxotungstate in the hybrid nanomaterial. The catalytic performance and turnover frequencies (TOFs) of the prepared hybrid nanomaterials as heterogeneous catalyst were investigated in the epoxidation of olefins and allylic alcohols with H2O2 as oxidant. This catalyst could be reused for five runs without significant loss of the activity and stability.