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    A PROCESS FOR THE PREPARATION OF GLYOXYLIC HEMIACETAL ESTERS
    51.
    发明专利
    A PROCESS FOR THE PREPARATION OF GLYOXYLIC HEMIACETAL ESTERS 未知

    公开(公告)号：ZA859675B

    公开(公告)日：1986-08-27

    申请号：ZA859675

    申请日：1985-12-19

    Applicant: HOECHST AG

    Inventor： DRISCOLL ROBERT KENNETH ,  LEUPOLD ERNST INGO ,  EBERTZ WOLFGANG

    IPC: C07C67/31 ,  C07C67/313 ,  C07C69/67 ,  C07C69/708 ,  C07C69/716 ,  C07C

    Abstract: The invention relates to a process for the preparation of glyoxylic hemiacetal esters, in which first glycolic esters are oxydehydrogenated to give glyoxylic esters, and then the latter are reacted with an alcohol. The gaseous reaction mixture formed in the oxydehydrogenation is introduced, together with an excess of an alcohol which is suitable as an entraining agent, into a distillation column and then the water of reaction is distilled overhead together with other low-boilers and part of the excess alcohol, the glyoxylic hemiacetal ester and the remainder of the excess alcohol resulting as the bottom product. In a variant of the process, use is made of an additional inert entraining agent whose azeotrope with water boils below 90 DEG C. and below the alcohol which is used, and then the water of reaction is distilled overhead with the assistance of this entraining agent.

    PROCESS FOR THE ISOMERIZATION OF HALOGENATED THIOPHENES
    53.
    发明专利
    PROCESS FOR THE ISOMERIZATION OF HALOGENATED THIOPHENES 未知

    公开(公告)号：ZA853944B

    公开(公告)日：1986-01-29

    申请号：ZA853944

    申请日：1985-05-24

    Applicant: HOECHST AG

    Inventor： EICHLER KLAUS ,  LEUPOLD ERNST INGO

    IPC: C07D333/28 ,  C07D

    Abstract: The invention relates to a process for the isomerization of halogenated thiophenes on zeolite catalysts. In this manner, in particular, 2-chlorothiophene is isomerized to 3-chlorothiophene and 2-bromothiophene is isomerized to 3-bromothiophene. Particularly suitable zeolites are synthetic zeolites of the pentasil, mordenite or faujasite type in their acid form.

    55.
    发明专利
    未知

    公开(公告)号：BR8500139A

    公开(公告)日：1985-08-20

    申请号：BR8500139

    申请日：1985-01-11

    Applicant: HOECHST AG

    Inventor： DRISCOLL ROBERT KENNETH ,  LEUPOLD ERNST INGO ,  EBERTZ WOLFGANG ,  WUNDER FRIEDRICH

    IPC: C07C69/67 ,  B01J19/32

    Abstract: 1. A process for the preparation of a glyoxylic acid ester by oxydehydrogenation of the corresponding glycolic acid ester in the gas phase over a supported catalyst in a tubular reactor, wherein the catalyst support consists of at least one cylindrical monolith, the monolith essentially having the same diameter as the reactor tube and containing channels 1 to 10 mm in diameter which lead from the inlet to the outlet of the reactor tube, and wherein 60 to 90% of the volume of the monolith is formed by hollow spaces.

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