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    Process for the preparation of 2,3,4,6-tetrachlorophenol
    12.
    发明专利
    Process for the preparation of 2,3,4,6-tetrachlorophenol 未知

    公开(公告)号：FR2636942A1

    公开(公告)日：1990-03-30

    申请号：FR8812713

    申请日：1988-09-23

    Applicant: RHONE POULENC CHIMIE

    Inventor： DESMURS JEAN-ROGER ,  JOUVE ISABELLE

    IPC: C07C37/62

    Abstract: The present invention relates to an improved process for the preparation of 2,3,4,6-tetrachlorophenol by chlorination of 2,4,6-trichlorophenol. There has now been found a process for the chlorination, by gaseous chlorine, of 2,4,6-trichlorophenol in a molten medium to 2,3,4,6-tetrachlorophenol, containing a small proportion of pentachlorophenol, characterised in that the reaction is carried out in the presence of an effective amount: - of a zirconium, hafnium, tellurium, antimony or niobium halide or of one of their precursers, - and/or of a strong protonic acid. The halides which can be used as catalysts are the chlorides, bromides, iodides and fluorides of zirconium, hafnium, tellurium, antimony and niobium.

    Process for the preparation of 2,3,4,6-tetrachlorophenol
    13.
    发明专利
    Process for the preparation of 2,3,4,6-tetrachlorophenol 未知

    公开(公告)号：FR2634759A1

    公开(公告)日：1990-02-02

    申请号：FR8810534

    申请日：1988-07-29

    Applicant: RHONE POULENC CHIMIE

    Inventor： DESMURS JEAN-ROGER ,  JOUVE ISABELLE

    IPC: C07C37/62

    Abstract: The present invention relates to an improved process for the preparation of 2,3,4,6-tetrachlorophenol by chlorination of 2,4,6-trichlorophenol. A process has now been found for the chlorination, by gaseous chlorine, of 2,4,6-trichlorophenol in molten medium to 2,3,4,6-tetrachlorophenol containing a small proportion of pentachlorophenol, characterized in that the reaction is carried out in the presence of an effective amount: - of an aluminium halide or of one of its precursors - and of a primary, secondary or tertiary amine. f

    14.
    发明专利
    未知

    公开(公告)号：FR2611706B1

    公开(公告)日：1989-06-16

    申请号：FR8703209

    申请日：1987-03-05

    Applicant: RHONE POULENC CHIMIE

    Inventor： DESMURS JEAN ,  JOUVE ISABELLE

    IPC: C07C67/00 ,  C07C201/00 ,  C07C205/22 ,  C07C205/26 ,  C07C79/32

    Abstract: The chloronitrophenols, e.g., 2,6-dichloro-4-nitrophenol (a known agrochemical/pharmaceutical intermediate), are efficiently prepared by chlorinating ortho- or para-nitrophenol with gaseous chlorine, characteristically in the molten state, and in the presence of a catalytically effective amount of a primary, secondary or tertiary amine.

    15.
    发明专利
    未知

    公开(公告)号：FR2730730B1

    公开(公告)日：1997-04-04

    申请号：FR9501926

    申请日：1995-02-20

    Applicant: RHONE POULENC CHIMIE

    Inventor： METIVIER PASCAL ,  MALIVERNEY CHRISTIAN ,  JOUVE ISABELLE

    IPC: B01J27/053 ,  C07B61/00 ,  C07C45/65 ,  C07C45/67 ,  C07C47/575 ,  C07C47/58 ,  C07C51/15 ,  C07C51/353 ,  C07C51/367 ,  C07C51/373 ,  C07C65/21

    Abstract: PCT No. PCT/FR96/00241 Sec. 371 Date Oct. 16, 1996 Sec. 102(e) Date Oct. 16, 1996 PCT Filed Feb. 14, 1996 PCT Pub. No. WO96/26175 PCT Pub. Date Aug. 29, 1996The subject of the present invention is a process for the preparation of a 4-hydroxybenzaldehyde carrying at least one substituent in the position ortho to the OH group. It more particularly relates to the preparation of 3-methoxy-4-hydroxybenzaldehyde and of 3-ethoxy-4-hydroxybenzaldehyde. The process for the preparation of a substituted 4-hydroxybenzaldlehyde, substituted at least in the 3 position by an alkoxy group, is characterized in that it comprises subjecting a substituted phenol compound, substituted at least in the 2 position by an alkoxy group and in which the 4 and 6 positions are free, to a first stage of carboxylation in the 6 position, then to a stage of hydroxymethylation in the 4 position, followed by a stage of oxidation of the hydroxymethyl group to a formyl group, and finally to a last decarboxylation stage.\!

    16.
    发明专利
    未知

    公开(公告)号：FI964190A

    公开(公告)日：1996-10-18

    申请号：FI964190

    申请日：1996-10-18

    Applicant: RHONE POULENC CHIMIE

    Inventor： METIVIER PASCAL ,  JOUVE ISABELLE ,  MALIVERNEY CHRISTIAN

    IPC: B01J27/053 ,  C07B61/00 ,  C07C45/65 ,  C07C45/67 ,  C07C47/575 ,  C07C47/58 ,  C07C51/15 ,  C07C51/353 ,  C07C51/367 ,  C07C51/373 ,  C07C65/21 ,  C07C

    Abstract: PCT No. PCT/FR96/00241 Sec. 371 Date Oct. 16, 1996 Sec. 102(e) Date Oct. 16, 1996 PCT Filed Feb. 14, 1996 PCT Pub. No. WO96/26175 PCT Pub. Date Aug. 29, 1996The subject of the present invention is a process for the preparation of a 4-hydroxybenzaldehyde carrying at least one substituent in the position ortho to the OH group. It more particularly relates to the preparation of 3-methoxy-4-hydroxybenzaldehyde and of 3-ethoxy-4-hydroxybenzaldehyde. The process for the preparation of a substituted 4-hydroxybenzaldlehyde, substituted at least in the 3 position by an alkoxy group, is characterized in that it comprises subjecting a substituted phenol compound, substituted at least in the 2 position by an alkoxy group and in which the 4 and 6 positions are free, to a first stage of carboxylation in the 6 position, then to a stage of hydroxymethylation in the 4 position, followed by a stage of oxidation of the hydroxymethyl group to a formyl group, and finally to a last decarboxylation stage.\!

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