甲基三氧化铼催化过氧化氢对烯烃的环氧化

The epoxidation of olefins with hydrogen peroxide catalyzed by methyltrioxorhenium

环氧化物在化学工业、有机合成以及制药等诸多领域具有广泛应用,通常由烯烃的环氧化制备.传统的环氧化方法由于伴生有机副产物,导致对环境产生污染并存在分离问题.过渡金属配合物特别是甲基三氧化铼(MTO)催化的过氧化氢(H2O2)对烯烃环氧化可克服传统环氧化方法的缺点,但MTO中心铼原子的酸性导致环氧化物开环生成二醇以及MTO不能循环使用限制了其大规模使用.本文总结了本课题组近些年为改进MTO催化30%H2O2环氧化烯烃性能进行研究的结果.内容包括吡啶席夫碱双齿配体的合成与应用、双哌啶衍生物双齿配体的合成与应用、双离子及离子液体配体的合成及应用以及MCM-41负载MTO的制备及其催化性能.这些方法提高了MTO催化30%H2O2环氧化烯烃性的选择性,有助于进一步完善MTO/H2O2烯烃环氧化体系.

Epoxides are widely used in chemical industry,organic and pharmaceutical synthesis.Generally,epoxides are prepared from the epoxidation of olefins.Traditional epoxidation methods lead to environmental pollution and separation problems due to the associated organic by-products.The epoxidation with hydrogen peroxide(H2O2) catalyzed by transition metal complexes especially methyltrioxorhenium can overcome the above shortcomings.However,It can not be applied in large scale due to the disadvantage of inherently acidic of the central Re atom leading to the epoxides to diols and the difficulty of recycle usage.In the paper,we summary the results investigated by us for improving the epoxidation of olefins with H2O2as oxidant catalyzed by MTO.The contents include the synthesis and application of pyridine-Schiff base bidentate ligands,the synthesis and application of bispidine derivative bidentate ligands,synthesis and application of zwitterion and ionic liquid ligands and the preparation and catalytic performances on epoxidation of MCM-41 supported MTO.These methods have increased the epoxidation selectivity largely and are helpful to improve the epoxidation of olefins with MTO/H2O2system.