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    Oxidation process
    285.
    发明授权
    Oxidation process 失效
    氧化工艺

    公开(公告)号：US4943358A

    公开(公告)日：1990-07-24

    申请号：US323976

    申请日：1989-03-15

    Applicant: Kenneth M. Dear ,  Philip J. Turner

    Inventor： Kenneth M. Dear ,  Philip J. Turner

    IPC: B01J19/12 ,  C07C45/00 ,  C07C45/30 ,  C07C49/784 ,  C07C49/786 ,  C07C49/813 ,  C07C67/00 ,  C07C201/00 ,  C07C201/12 ,  C07C205/46 ,  C07C309/44

    CPC classification number: C07C49/813 ,  C07C45/30 ,  C07C49/784

    Abstract: It is desired to find an alternative way to produce benzophenones or substituted benzophenones which does so selectively and avoids the problems of previous methods that use, for example, large amounts of an aluminium chloride catalyst or nitric acid.In the invention process, a diphenyl methane starting material (DPM) in a hydrophobic phase is oxidized in a photolytic process by contact with an aqueous phase containing greater than 1 mole of HBr and at least 1.5 moles of H.sub.2 O.sub.2, both per mole of DPM, the radiation being capable of dissociating bromine to its radicals, and especially using light of wavelength 600 to 250 nm. Preferably, a reaction temperature of around 50.degree. to 65.degree. C., is used, the organic solvent comprising a suitably boiling chlorinated carbon or hydrocarbon. The H.sub.2 O.sub.2 is introduced progressively into the reaction mixture. The benzophenone product is recovered substantially in the organic phase, whereas most of the bromine/bromide is retained in the aqueous phase which can be re-employed in a subsequent oxidation of DPM, possibly after restoration of the bromide to its initial concentration.In a modification to the process, by suitably controlling the mole ratios of bromide and H.sub.2 O.sub.2 to DPM at about 1:1:1, and preferably using a reaction temperature of about ambient to 35.degree. C., the DPM can be substituted by a single bromine atom on the methane carbon also with good selectively, instead of being oxidized to the benzophenone.

    Phenylalkenylcarboxylic acids and their esters
    286.
    发明授权
    Phenylalkenylcarboxylic acids and their esters 失效
    苯基链烯基羧酸及其酯

    公开(公告)号：US4933001A

    公开(公告)日：1990-06-12

    申请号：US217563

    申请日：1988-07-11

    Applicant: Peter Plath ,  Karl Eicken ,  Norbert Goetz ,  Jochen Wild ,  Norbert Meyer ,  Bruno Wuerzer

    Inventor： Peter Plath ,  Karl Eicken ,  Norbert Goetz ,  Jochen Wild ,  Norbert Meyer ,  Bruno Wuerzer

    IPC: A01N37/22 ,  A01N37/32 ,  C07C67/00 ,  C07C201/00 ,  C07C205/56 ,  C07C227/00 ,  C07C229/40 ,  C07C229/44 ,  C07D209/48

    CPC classification number: C07D209/48 ,  A01N37/32

    Abstract: Phenylalkenylcarboxylic acid and esters thereof of the general formula I ##STR1## where X is hydrogen or fluorine, R.sup.1 is hydrogen, C.sub.1 C.sub.6 -alkyl, C.sub.5 - or C.sub.6 -cycloalkyl, (C.sub.1 -C.sub.4 -alkoxy)-C.sub.2 -C.sub.4 -alkyl or (C.sub.1 -C.sub.4 -alkylthio)-C.sub.2 -C.sub.4 -alkyl; W is a divalent radical --CH.dbd.CR.sup.2 --; --CH.dbd.CY--; --CH.dbd.CR.sup.2 --CH.sub.2 --; --CH.dbd.CR.sup.2 --CH.dbd.CR.sup.3 -- or ##STR2## where Y is chlorine or bromine and R.sup.2 and R.sup.3 are each hydrogen or C.sub.1 -C.sub.4 -alkyl, with the proviso that X is not F when W is --CH.dbd.CR.sup.2 --, their manufacture, and their use as herbicides.

    Abstract translation: 苯基链烯基羧酸及其通式I的酯其中X是氢或氟，R 1是氢，C 1 -C 6 - 烷基，C 5 - 或C 6 - 环烷基，（C 1 -C 4 - 烷氧基）-C 2 -C 4烷基或 （C 1 -C 4 - 烷硫基）-C 2 -C 4 - 烷基; W是二价基团-CH = CR2-; -CH = CY-; -CH = CR 2 -CH 2 - ; -CH = CR2-CH = CR3-或其中Y是氯或溴，R2和R3各自是氢或C1-C4-烷基，条件是当W是-CH = CR2-时，X不是F， 它们的制造及其作为除草剂的用途。

    Bromination
    287.
    发明授权
    Bromination 失效
    溴化

    公开(公告)号：US4923580A

    公开(公告)日：1990-05-08

    申请号：US326065

    申请日：1989-03-20

    Applicant: Philip J. Turner ,  Martin Jeff ,  Kevan M. Reeve

    Inventor： Philip J. Turner ,  Martin Jeff ,  Kevan M. Reeve

    IPC: B01J19/12 ,  C07B39/00 ,  C07C17/00 ,  C07C17/14 ,  C07C22/04 ,  C07C25/02 ,  C07C25/13 ,  C07C45/43 ,  C07C67/00 ,  C07C201/00 ,  C07C201/12 ,  C07C201/14 ,  C07C205/11 ,  C07C205/12 ,  C07C303/22 ,  C07C309/30

    CPC classification number: C07B39/00 ,  C07C201/12

    Abstract: Selective bromination of alkylarenes to the alpha dibrominated derivative is desirable as a precursor for the selective production of, for example, the corresponding aromatic aldehyde.Improvements in the extent of selectivity of the product and/or its rate of production can be obtained by employing a photolytic reaction between the substrate, hydrogen peroxide and hydrogen bromide using mole ratios of H.sub.2 O.sub.2 : substrate of about 2.8:1 or higher, preferably 3,2: to 3.5:1 and of bromide:substrate of over 2.5:1, preferably about 2.8:1 to 3.2:1 and progressive controlled introduction of the H.sub.2 O.sub.2, the reaction being carried out in the presence of a substantial amount of an organic solvent, and preferably more than 5.5 volumes per volume of substrate, whilst irradiating with light preferably having principal emissions in the range of 250 to 600 nm. The reaction mixture is preferably maintained at 50.degree. to 60.degree. C. The reaction often takes from 5 to 12 hours, of which period hydrogen peroxide is introduced progressively into the reaction mixture during preferably the first 3 to 5 hours. The process is especially suitable for deactivated alkylarenes, such as o-nitrotoluene.

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