Synthesis Of Ni₂（bdc）₂（dabco） And Its Applications In Heterogeneous Catalysis

Metal-organic frameworks(MOFs) are a newly-developed class of porous materials with a vast prospect. MOFs generally consist of metal ions or metal clusters bridged by organic linkers. MOFs have proven to be of great importance to various types of applications, owing to the inherent nature of MOF: enormous surface area, ultra-high porosity and most importantly, tunable structures.Over the past several decades, MOFs have been extensively researched and applied in a lot of areas including heterogeneous catalysis, gas adsorption/separation, molecular sensor, pharmaceuticals and so on, which makes MOFs a class of promising materials. MOFs are now one of the hottest research field and experiencing an explosive development. Our research on the use of MOFs is basically focusing on heterogeneous catalysis, because of the easily recoverable characteric of the catalysts, compared with homogeneous catalysis.The selective oxidation of alkanes is one of the most important transformations in chemical industry and research of organic chemistry. However, due to the chemical stability of alkanes, the oxidation reactions are usually difficult and get very low conversion and selectivity. The control of conversion and selectivity of the oxidation of alkanes is thus important. In our research, we designed a heterogeneous catalyst Ni@C-N prepared from the calcination of a Ni-based MOF, Ni2(bdc)2(dabco)(Ni-MOF). First we employed the catalyst to the oxidation of ethylbenzene in order to test the catalysis activity. The results suggested that the catalyst could remarkably increase the conversion of ethylbenzene and the selectivity to acetophenone. We further studied the general applicapability of the catalyst by applying it to the oxidation reaction of cyclohexane and other alkanes. The catalyst was demonstrated to be highly active and selective for oxidation of a variety of saturated C-H bonds, affording their corresponding oxidation products in good to excellent yields. Furthermore, the catalysts could be recycled and reused for at least four times without any significant loss in activity and selectivity under the investigated conditions.Secondary amine are important intermediates in organic chemistry. The-NH- bond can be found in various chemicals. Current methods to prepare secondary amines often include the use of hazardous base harmful to the environment and amines that are usually expensive. In this work, we introduce a highly efficient catalyst Pd/Ni-MOF prepared from loading Pd nanoparticles to Ni-MOF using sol-gel method. The catalyst revealed high catalytic activity and selectivity in the coupling of nitriles to prepare secondary amines. The unsaturated central metal Ni could activate nitriles, and the organic linker DABCO act as base to promote isopropyl alchohol to donate protons, thus Pd/Ni-MOF show high activity in the transfer-hydrogenation of nitriles.