An efficient and recyclable Cu@UiO-67-BPY catalyst for the selective oxidation of alcohols and the epoxidation of olefins†
Abstract
A facile synthesis of the copper-doped Cu@UiO-67-BPY metal–organic framework material has been carried out using an efficient one-pot approach. The as-synthesized Cu@UiO-67-BPY catalyst was employed as an efficient heterogeneous catalyst towards two different aerobic oxidation reactions. Three different copper salt precursors were investigated for screening of the optimal conditions for the synthesis of the Cu@UiO-67-BPY catalyst. The results suggest that the CuCl2-derived Cu@UiO-67-BPY catalyst provides the highest outcome in terms of conversion and selectivity. The optimal catalyst was fully characterized using scanning electron microscopy, X-ray diffraction, thermogravimetric analysis, Fourier transform infrared spectra, X-ray photoelectron spectroscopy, and the Brunauer–Emmett–Teller method. This CuCl2-UiO-67-BPY catalyst demonstrated enhanced catalytic properties and better recycling ability in comparison with our previously reported UiO-66-Sal-CuCl2 catalyst. Due to the higher catalytic selectivity derived from the CuCl2-UiO-67-BPY catalyst, the olefin epoxidation reaction was enabled under mild catalytic reaction conditions. Furthermore, the as-synthesized CuCl2-UiO-67-BPY catalyst can be recycled and reused at least 10 times without compromising the yield or selectivity significantly.