A Mg–Al layered-double hydroxide (LDH) intercalated by sulphonato-salhen-chromium (III) complex was prepared and then used to the selective oxidation of benzyl alcohol by 30% H2O2. without any organic solvent, phase transfer catalyst or additive. The results revealed that the LDH hosted chromium complex exhibited much higher catalytic performance than its homogeneous analogue. Under the optimal reaction conditions, the highest conversion of benzyl alcohol reached 52.1%, with 100% of the selectivity to benzyldehyde.
A fluorine anion modified CuNiAl hydrotalcite (CuNiAl-LDH (F-)) was prepared for the selective oxidation of glycerol (GLY) using O2 as oxidant. It was found that the obtained catalyst with typical layer structures of hydrotalcite compounds was an effective heterogeneous catalyst in GLY oxidation. Under the present conditions, the main product was the C3 oxygenated products of primary alcohol glyceric acid (GLYAC). The highest conversion of GLY reached 32.0% with 58.1% of the selectivity to GLYAC.
A series of transition metal alanine-salicylaldehyde Schiff base chromium (III) complexes immobilized on MCM-41 were prepared and characterized by various physico-chemical measurements such as FIIR, XRD, HRTEM, N2 sorption and elemental analysis. The immobilized complexes were effective and stable catalysts for the epoxidation of styrene and cyclohexene with 30% hydrogen peroxide. Moreover, the metal centers were found to play important roles in the catalytic performance of immobilized complex catalysts.
The Mg-Al mixed oxides were deposited on the MCM-41 via the coprecipitation followed by thermal decomposition and characterized by many techniques. In the transesterification of glycerol (GL) with dimethyl carbonate (DMC), the resulting supported catalysts exhibited much higher catalytic performance than the pure Mg-Al mixed oxides, which was ascribed to the increased basicity. Under the optimal reaction conditions, the obtained data showed that at DMC/glycerol molar ratio of 3:1, catalyst loading of 0.3 g and reaction temperature of 373 K, the glycerol conversion and glycerol carbonate yield from the process was 98.7 % and 92.5%, respectively.
A series of chromium (III) Schiff base complexes immobilized on MCM-41 were prepared and used for the selective oxidation of cyclohexanol with 30% hydrogen peroxide. The results revealed that the immobilized complexes were active catalysts and exhibited much higher catalytic performance than their homogeneous analogue. This could be ascribed to the dispersion effect of the support. Simultaneously, the linker flexibility and the surface property of support were also found to play important roles in the catalytic performance of immobilized complexes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.