Preparation of .alpha.-tocopherol or .alpha.-tocopheryl acetate by
reacting trimethylhydroquinone and phytol or isophytol, with recycling
of the zinc halide condensation catalyst
    1.
    发明授权
    Preparation of .alpha.-tocopherol or .alpha.-tocopheryl acetate by reacting trimethylhydroquinone and phytol or isophytol, with recycling of the zinc halide condensation catalyst 失效
    通过三甲基对苯二酚和植物醇或异植醇反应制备α-生育酚或α-生育酚乙酸酯,再加上卤化锌缩合催化剂

    公开(公告)号:US6005122A

    公开(公告)日:1999-12-21

    申请号:US990092

    申请日:1997-12-12

    IPC分类号: B01J27/138 C07D311/72

    CPC分类号: C07D311/72 B01J27/138

    摘要: A process for preparing .alpha.-tocopherol or .alpha.-tocopheryl acetate by reacting 2,3,5-trimethylhydroquinone with isophytol or phytol in the presence of a zinc halide condensation catalyst and a proton donor in a solvent with or without subsequent esterification with acetic anhydride, which comprisesA. carrying out the reaction in a nonpolar solvent which is only slightly water-miscible, if at all andB. introducing the required zinc halide into the reaction in the form of a mixture of from 1 to 4 mol of water per mol of zinc halide.The possibility of introducing the zinc halide required in the process according to the invention in the form of a mixture of zinc halide and water which can be readily handled and metered at from 50 to 200.degree. C. without impairing the yield and purity of the tocopherol opens the way to an advantageous recycling of the zinc halide after the reaction by separating off or extracting and recycling the zinc halide in the form of a from 60 to 90% strength by weight solution or pumpable magma.

    摘要翻译: 在卤化锌缩合催化剂和质子供体存在下,使2,3,5-三甲基氢醌与异麦芽糖醇或植物醇在溶剂中反应制备α-生育酚或α-生育酚乙酸酯的方法,其中或不用随后用乙酸酐酯化, 其包括A.在非极性溶剂中进行反应,所述非极性溶剂仅仅是轻微的水混溶性的,如果有的话,则B.将所需的卤化锌以每摩尔1至4摩尔水的混合物的形式引入反应中 的卤化锌。 将本发明方法中所需的卤化锌以卤化锌和水的混合物的形式引入卤化物的可能性,其可以在50-200℃下容易地处理和计量,而不损害生育酚的产率和纯度 打开通过分离或提取和重新使用60至90%重量浓度的溶液或可泵送岩浆形式的卤化锌,从而在反应之后有效地再循环卤化锌。