Preparation of tetrahydrofuran using a supported transition metal
    7.
    发明授权
    Preparation of tetrahydrofuran using a supported transition metal 失效
    使用负载的过渡金属制备四氢呋喃

    公开(公告)号:US5166370A

    公开(公告)日:1992-11-24

    申请号:US684407

    申请日:1991-04-12

    IPC分类号: C07C29/141 C07D307/08

    CPC分类号: C07D307/08 C07C29/141

    摘要: A process for producing tetrahydrofuran, 1,4-butanediol, and 2-methyl-1,3,-propanediol is disclosed. A mixture containing 4-hydroxybutanal and 3-hydroxy-2-methylpropanal is hydrogenated in the presence of a transition metal supported on a weakly acidic ion-exchange resin or zeolite-type material to give tetrahydrofuran as the major product, and 1,4-butanediol and 2-methyl-1,3-propanediol as minor products. High yields of 2-methyl-1,3-propanediol can be obtained.

    摘要翻译: 公开了一种生产四氢呋喃,1,4-丁二醇和2-甲基-1,3-丙二醇的方法。 将含有4-羟基丁醛和3-羟基-2-甲基丙醛的混合物在负载在弱酸性离子交换树脂或沸石型材料上的过渡金属存在下氢化,得到四氢呋喃作为主要产物, 丁二醇和2-甲基-1,3-丙二醇作为次要产物。 可以获得高产率的2-甲基-1,3-丙二醇。

    Preparation of methylene diphenylene diisocyanates and polymethylene
polyphenylene poly (isocyanates) using an organic sulfonic acid promoter
    8.
    发明授权
    Preparation of methylene diphenylene diisocyanates and polymethylene polyphenylene poly (isocyanates) using an organic sulfonic acid promoter 失效
    使用有机磺酸促进剂制备亚甲基二亚苯基二异氰酸酯和聚亚甲基聚亚苯基聚(异氰酸酯)

    公开(公告)号:US4978779A

    公开(公告)日:1990-12-18

    申请号:US321496

    申请日:1989-03-09

    IPC分类号: C07C263/06

    CPC分类号: C07C263/06

    摘要: An improved process is provided for the preparation of methylene diphenylene diisocyanates (MDI) and polymethylene polyphenylene poly (isocyanates) (PMDI) by the thermal decomposition of a methylene diphenylene bis (dialkylurea) or a polymethylene polyphenylene poly (alkylurea) in a solvent in the presence of an organic sulfonic acid or sulfonated aromatic ion exchange resin as a promoter for conversion of the urea groups to the corresponding isocyanate.

    摘要翻译: 提供了一种通过亚甲基二亚苯基双(二烷基脲)或多亚甲基聚亚苯基聚(烷基脲)在溶剂中热分解制备亚甲基二亚苯基二异氰酸酯(MDI)和多亚甲基多亚苯基聚(异氰酸酯)(PMDI) 存在有机磺酸或磺化芳族离子交换树脂作为将脲基团转化成相应的异氰酸酯的促进剂。