有机碱协同SnCl2·2H2O催化葡萄糖转化制备乳酸甲酯

Preparation of methyl lactate from glucose catalyzed by organic alkali promoted SnCl_2 catalyst

以SnCl_2·2H_2O为催化剂,对比13种不同有机碱在催化葡萄糖醇解制备乳酸甲酯过程中的助催化作用,包括1-甲基咪唑、咪唑、1-乙烯基咪唑、三苯基膦、苯胺、邻菲罗啉、喹啉、2,6-二甲基吡啶、4,4-联吡啶、吡啶、4-甲基吡啶、2,6-二溴吡啶、2-溴吡啶等有机碱,考察反应时间、反应温度、有机碱与SnCl_2物质的量比的影响。结果表明,以2-溴吡啶为助催化剂,且与SnCl_2物质的量比为1∶1时,在220℃、2 MPa的氮气气氛反应6 h,乳酸甲酯收率最高,为44.6%。

In this work,the promotional effects of thirteen kinds of organic alkali,including phenanthroline,1-methylimidazole,imidazole,1-vinylimidazole,triphenylphosphine,aniline,quinolone,2,6-dimethylpyridine,4,4-bipyridine,pyridin,4-methylpyridine,2,6-dibromopyridine,and2-bromidepyridine on the SnCl2·2H2O catalyst for theconversion of glucose to prepare methyl lactate were compared.Moreover,the influences of the reaction time,reaction temperature and the molar ratio of organic alkali to SnCl2on the conversion of glucose to prepare methyl lactate were also investigated.The highest methyl lactate yield of45%was achieved over2-bromidepyridine promoted SnCl2catalyst(2-bromidepyridine/SnCl2molar ratio=1)at220℃,2MPa N2pressure for6h