介孔有机无机杂化材料的合成和表征及在Pinacol重排反应中的研究

以巯丙基-三乙氧基硅烷为有机硅源,采用接枝法合成了磺酸基功能化有机无机杂化材料(MCM-SO3H).XRD、FT-IR、BET的研究表明,磺酸基功能化介孔有机无机杂化材料具有非常高的比表面积和规整的六方孔道结构.酸性测定表明,MCM-SO3H含酸量为0.40mmolH /g.MCM-SO3H对pinacol重排反应具有很高的催化活性,在反应温度为383K时,pinacol的转化率接近100%,pinacolone的选择性达到90%左右.反应温度、反应时间、催化剂用量和溶剂对pinacol重排反应有很大的影响提高反应温度、延长反应时间和增加催化剂的用量,均可提高pinacol的转化率和pinacolone的选择性.中等极性溶剂有利于pinacol重排反应.

Synthesis, Chracterization of Mesporous Organic-inorganic Hybrid and Its Application on Piancol Rearrangement

The sulfonic functionalized mesoporous organic-inorganic hybrid (MCM-SO_ 3 H) was synthesized by reaction of (3-mercaptopropyl)trimethoxysilane with MCM-41 and subsequent oxidation by H_ 2 O_ 2 . XRD, FT-IR, BET characterizations showed that the hybrid (MCM-SO_ 3 H) still maintained the mesopores. The amount of the acid site of MCM-SO_ 3 H measured by NaOH titration was 0.40 mmolH /g. The mesoporous organic-inorganic hybrid (MCM-SO_ 3 H) was an efficient catalyst for pinacol rearrangement reaction under mild reaction condition. The effects of temperature, reaction time, amount of catalyst and polarity of solvent on the catalytic properties were also investigated. The conversion of pinacol and selectivity of pinacolone were improved by increasing reaction temperature, prolonging reaction time and increasing amount of catalyst. Higher conversion of pinacol and selectivity of pinacolone were achieved by using medium polarity solvents.