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    Preparation of sugar ketals
    1.
    发明授权
    Preparation of sugar ketals 失效
    糖缩酮的制备

    公开(公告)号：US4681936A

    公开(公告)日：1987-07-21

    申请号：US826317

    申请日：1986-02-05

    申请人： Klaus-Peter Pfaff ,  Joachim Paust ,  Horst Hartmann

    发明人： Klaus-Peter Pfaff ,  Joachim Paust ,  Horst Hartmann

    IPC分类号： C07H1/00 ,  B01J31/00 ,  C07B61/00 ,  C07H9/04

    CPC分类号： C07H9/04

    摘要： Sugar ketals are prepared by reacting a sugar with a ketone in the presence of an acid catalyst by a process in whichA. a molecular boron trifluoride compound or trifluoromethanesulfonic acid is used in an amount of only from 0.01 to 10% by weight, based on the sugar used,B. up to a 30-fold molar excess of the ketone is used andC. the water formed during the reaction is removed continuously from the reaction mixture.In a particularly advantageous embodiment of the process, the boron trifluoride is used in the form of boron trifluoride etherate and, when the reaction is complete, this compound or the trifluoromethanesulfonic acid is rendered ineffective under non-aqueous conditions, after which the ketone is evaporated off and the reaction mixture is then subjected to fractional distillation. The process is particularly important for the reaction of L-sorbose with acetone to obtain 2,3:4,6-di-O-isopropylidene-L-sorbofuranose, which is required for the synthesis of ascorbic acid.

    摘要翻译： 糖缩成物是通过在酸催化剂存在下使糖与酮反应的方法制备的，其中A为分子三氟化硼化合物或三氟甲磺酸的用量，其量仅为0.01至10重量％，基于 使用的糖，B.使用高达30倍摩尔过量的酮，并且C.从反应混合物中连续除去反应期间形成的水。 在该方法的特别有利的实施方案中，三氟化硼以三氟化硼醚合物的形式使用，当反应完成时，该化合物或三氟甲磺酸在非水性条件下变得无效，之后酮蒸发 然后将反应混合物进行分馏。 该方法对于L-山梨糖与丙酮的反应特别重要，得到合成抗坏血酸所需的2,3：4,6-二-O-异亚丙基-L-山梨糖。

    Method for obtaining oligomers of polytetrahydofurane or tetrahydrofurane
    3.
    发明申请
    Method for obtaining oligomers of polytetrahydofurane or tetrahydrofurane 有权
    获得聚四氢呋喃或四氢呋喃的低聚物的方法

    公开(公告)号：US20060266635A1

    公开(公告)日：2006-11-30

    申请号：US10563421

    申请日：2004-06-19

    申请人： Volkmar Menger ,  Michael Schwarztrauber ,  Martin Haubner ,  Klaus-Peter Pfaff

    发明人： Volkmar Menger ,  Michael Schwarztrauber ,  Martin Haubner ,  Klaus-Peter Pfaff

    IPC分类号： B01D3/00

    CPC分类号： C08G65/20 ,  C08G65/30 ,  C08G65/3311 ,  Y10S203/24

    摘要： A process for obtaining oligomers of polytetrahydrofuran or of tetrahydrofuran copolymers from a methanolic crude product which contains polytetrahydrofuran or tetrahydrofuran copolymers and is obtained in the transesterification of the mono- and/or diesters of polytetrahydrofuran or tetrahydrofuran copolymers with methanol, which comprises a) removing the majority of the methanol from the crude product in a first distillation stage, b) separating the resulting bottom product by distillation into a top fraction comprising the oligomers of polytetrahydrofuran or of tetrahydrofuran copolymers, and polytetrahydrofuran or tetrahydrofuran copolymer, c) condensing the oligomers of polytetrahydrofuran or of tetrahydrofuran copolymers out of the top fraction from stage b).

    摘要翻译： 从含有四氢呋喃或四氢呋喃共聚物的甲醇粗产物中获得聚四氢呋喃或四氢呋喃共聚物的低聚物的方法，是在聚四氢呋喃或四氢呋喃共聚物与甲醇的单酯和/或二酯的酯交换反应中获得的，该方法包括：a） 大部分来自粗产物的甲醇在第一蒸馏阶段，b）通过蒸馏将所得底部产物分离成包含聚四氢呋喃或四氢呋喃共聚物的低聚物的顶级馏分和聚四氢呋喃或四氢呋喃共聚物，c）将聚四氢呋喃的低聚物 或来自阶段b）的最高级分的四氢呋喃共聚物。

    Method for obtaining oligomers of polytetrahydofurane or tetrahydrofurane
    8.
    发明授权
    Method for obtaining oligomers of polytetrahydofurane or tetrahydrofurane 有权
    获得聚四氢呋喃或四氢呋喃的低聚物的方法

    公开(公告)号：US07718041B2

    公开(公告)日：2010-05-18

    申请号：US10563421

    申请日：2004-06-19

    申请人： Volkmar Menger ,  Michael Schwarztrauber ,  Martin Haubner ,  Klaus-Peter Pfaff

    发明人： Volkmar Menger ,  Michael Schwarztrauber ,  Martin Haubner ,  Klaus-Peter Pfaff

    IPC分类号： B01D3/10 ,  C07C29/80 ,  C07D307/08

    CPC分类号： C08G65/20 ,  C08G65/30 ,  C08G65/3311 ,  Y10S203/24

    摘要： A process for obtaining oligomers of polytetrahydrofuran or of tetrahydrofuran copolymers from a methanolic crude product which contains polytetrahydrofuran or tetrahydrofuran copolymers and is obtained in the transesterification of the mono- and/or diesters of polytetrahydrofuran or tetrahydrofuran copolymers with methanol, which includes a) removing the majority of the methanol from the crude product in a first distillation stage, b) separating the resulting bottom product by distillation into a top fraction containing the oligomers of polytetrahydrofuran or of tetrahydrofuran copolymers, and polytetrahydrofuran or tetrahydrofuran copolymer, and c) condensing the oligomers of polytetrahydrofuran or of tetrahydrofuran copolymers out of the top fraction from stage b).

    摘要翻译： 从含有聚四氢呋喃或四氢呋喃共聚物的甲醇粗产物中获得聚四氢呋喃或四氢呋喃共聚物的低聚物的方法，是在聚四氢呋喃或四氢呋喃共聚物与甲醇的单酯和/或二酯的酯交换反应中获得的，其包括a） 大部分来自粗产物的甲醇在第一蒸馏阶段中，b）通过蒸馏将所得的底部产物分离成含有聚四氢呋喃或四氢呋喃共聚物的低聚物和四氢呋喃或四氢呋喃共聚物的顶级馏分，和c）将 聚四氢呋喃或来自阶段b）的顶级馏分中的四氢呋喃共聚物。