Preparation Of Metal-acid Bifunctional Catalytic Materials And Applications In Borylation

Organoboron compounds are widely used in pharmaceutical chemistry,synthetic chemistry and materials science.Currently,the synthesis methods mainly focus on the development of homogeneous catalytic system.Although the catalytic performance is highly efficient,homogeneous metal catalysts are often difficult to be recycled.Supported catalyst has attracted much attention because of its recyclable characteristics,which can effectively reduce the cost.In this thesis,a stable supported metal-acid bifunctional catalyst was prepared using acidic porous material as the support.It has high catalytic activity and stable recycling performance in borylation reaction,including borylation of olefin and direct alcohol borylation.Specific research contents are as follows:(1)The metal-acid bifocal catalyst was prepared by hydrothermal impregnation method using porous materials such as acidic molecular sieves as the carrier.The catalysts were characterized by high resolution transmission electron microscopy(HRTEM),X-ray diffraction(XRD),X-ray photoelectron spectrometer(XPS)and other instruments.HRTEM and XRD images showed that the prepared catalyst maintained the shape of the carrier molecular sieve and the particle size was within the range of 100-200 nm.No obvious metal particle agglomeration was observed on the carrier.EDS and XPS images showed that the presence of corresponding metal(copper)elements was detected.The results of mapping showed that the metal(copper)elements were uniformly distributed on the surface of the molecular sieve and the pore channels.These results confirm that the preparation process does not affect the structure of the carrier.(2)Use the prepared metal-acid bifunction catalyst to catalyze the boration of olefin.By exploring the influence of catalyst,catalyst amount,reaction temperature,additive on olefin borylation reaction,the optimal reaction conditions were determined,and the target product was obtained with higher separation yield.Metal-acid bifunctional catalysts are compatible for many alkenes with different electronic effects and steric hindrance.The metal-acid bifunctional catalyst showed good stability in the borylation of olefin.After 6 cycles of reaction,the target product was still obtained at 80%yield.(3)Using the prepared metal-acid bifunctional catalyst to explore the direct borylation of alcohol.The influences of catalyst,reaction time,additive,catalyst amount and other conditions on the direct borylation of alcohol were investigated to determine the optimal reaction conditions.The metal-acid bifunctional catalyst can effectively accommodate alcohols with different electronic effects and steric hindrance in the direct borylation of alcohols.The catalyst showed good catalytic stability in the direct borylation of alcohol.After 6 cycles of experiments,the target product was still obtained with a yield of 83%.