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    Process for the preparation of tetrachloro-1,4-benzoquinone
    2.
    发明专利
    Process for the preparation of tetrachloro-1,4-benzoquinone 未知

    公开(公告)号：DE4336323C1

    公开(公告)日：1995-03-09

    申请号：DE4336323

    申请日：1993-10-25

    Applicant: HOECHST AG

    Inventor： ARNDT OTTO DR ,  SCHUBERT HANS DR

    IPC: B01J27/128 ,  C07B61/00 ,  C07C46/00 ,  C07C46/06 ,  C07C46/10 ,  C07C50/24 ,  C10M131/10

    Abstract: Process for the preparation of tetrachloro-1,4-benzoquinone in high purity by allowing chlorine and concentrated hydrochloric acid to act on hydroquinone, in which process some of the hydroquinone to be employed is introduced into an amount of 20 to 37% strength aqueous hydrochloric acid whose molarity is 4 to 6 times the total amount of hydroquinone and which contains catalytic amounts of iron(III) ions and an anionic dispersant, chlorine gas whose molarity is 1.5 to 2.0 times the amount of total hydroquinone is passed into this solution at a temperature of 20 to 90 DEG C, the remaining hydroquinone is subsequently added in the form of a solid or in dissolved form, chlorine gas whose molarity is 1.5 to 2.0 is passed in, the concentration of the hydrochloric acid is maintained at 23-25% by adding water, and, finally, the temperature is raised to 100 to 107 DEG C while passing in more chlorine gas (molarity 1.7 to 2.5) and diluting with water down to a hydrochloric acid concentration of 20 to 22%.

    3.
    发明专利
    未知

    公开(公告)号：DE3869804D1

    公开(公告)日：1992-05-14

    申请号：DE3869804

    申请日：1988-02-03

    Applicant: HOECHST AG

    Inventor： ARNDT OTTO DR ,  PAPENFUHS THEODOR DR

    IPC: C07C50/24 ,  C07C37/62 ,  C07C45/00 ,  C07C46/00 ,  C07C46/06 ,  C07C67/00

    Abstract: (A) Hydroquinone in at least 12 molar proportions of 30-37% hydrochloric acid is treated at 5-50 deg.C with 3.8-4.2 molar proportions of 30-37% hydrochloric acid and 1.9-2.1 molar proportions of 50-35% hydrogen peroxide; (B) The resulting suspension (contg. essentially 2,5-dichlorohydroquinone) is heated to 45-55 deg.C; (C) The suspension is treated at 50-95 deg.C with 3.8-4.2 molar proportions of hydrochloric acid and 1.9-2.1 molar proportions of 50-35% hydrogen peroxide; and (D) The resulting suspension (consisting essentially of trichloro-1,4-benzoquinone) is treated at 95-115 deg.C with 1.9-2.1 molar proprtions of 30-37% hydrochloric acid and 0.95-1.05 molar proportions 50-35% hydrogen peroxide at such a rate that no chlorine gas is released; all molar ratios being based on the hydroquinone used. The reaction is pref. carried out in the presence of an acid- and chlorine-stable surface-active agent, pref. a sec. alkanesulphonate.

    Process for the preparation of tetrachloro-1,4-benzoquinone
    8.
    发明专利
    Process for the preparation of tetrachloro-1,4-benzoquinone 未知

    公开(公告)号：DE4405929C1

    公开(公告)日：1995-03-09

    申请号：DE4405929

    申请日：1994-02-24

    Applicant: HOECHST AG

    Inventor： ARNDT OTTO DR ,  TRONICH WOLFGANG DR

    IPC: B01J27/128 ,  C07B61/00 ,  C07C46/00 ,  C07C46/06 ,  C07C50/24

    Abstract: The invention relates to a process for the preparation of tetrachloro-1,4-benzoquinone in high purity by reacting chlorine and concentrated hydrochloric acid with hydroquinone, by a process in which some of the hydroquinone to be employed is introduced into 4 to 6 times the molar amount - based on the total amount of hydroquinone - of 20 to 37 % aqueous hydrochloric acid which contains catalytic amounts of iron(III) ions and an anionic dispersant, passing 1.5 to 2.0 times the molar amount - based on total hydroquinone - of chlorine gas into this solution at a temperature of 20 to 90 DEG C, subsequently adding the remainder of the hydroquinone as a solid or in dissolved form, passing in 1.5 to 2.0 times the molar amount of chlorine gas, during which process the hydrochloric acid concentration is first kept at 25 to 31 % by adding water, raising the temperature to 100 to 107 DEG C while passing in more chlorine gas (1.3 to 1.9 times the molar amount) and while diluting with water down to a hydrochloric acid concentration of 20 to 22 %, adding, after the passing-in of chlorine gas has ended, a higher-boiling organic solvent which is not miscible with hydrochloric acid in an amount of 0.15 to 1.0 part based on 1 part of tetrachloro-1,4-benzoquinone, or in an amount of approximately 1 - 10 % by weight, based on the reaction mixture, and subsequently subjecting the reaction mixture to thermal aftertreatment.

    SOLVATED SALTS OF 2,4-DINITROPHENYL CYANAMIDES, PROCESS FOR PREPARING THEM AND THEIR APPLICATION
    10.
    发明专利
    SOLVATED SALTS OF 2,4-DINITROPHENYL CYANAMIDES, PROCESS FOR PREPARING THEM AND THEIR APPLICATION 未知

    公开(公告)号：DE3165793D1

    公开(公告)日：1984-10-04

    申请号：DE3165793

    申请日：1981-10-29

    Applicant: HOECHST AG

    Inventor： ARNDT OTTO DR ,  PAPENFUHS THEODOR DR ,  TRONICH WOLFGANG DR

    IPC: C07C261/04 ,  C07C261/00 ,  C07C273/06 ,  C07C275/30 ,  C07C125/08 ,  C07C127/19

    Abstract: Compounds of the formula I in which X denotes hydrogen, fluorine, chlorine or bromine, Y and Z denote hydrogen, lower alkyl or lower alkoxy, M denotes sodium, potassium or one equivalent of calcium and L denotes a dipolar aprotic solvent, are obtained from compounds of the formula II in which X, Y and Z have the abovementioned meanings, and a metal cyanamide of the formula III M2N-CN in which M has the abovementioned meaning, in a dipolar aprotic solvent, which after the reaction is substantially removed, whereupon a lower molecular weight aliphatic alcohol is added to the residue and the product precipitated is isolated. Nitrophenylureas of the formula IV in which X, Y and Z have the abovementioned meanings, are obtained from the compounds of the formula I by acid hydrolysis.

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