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    Bromination
    277.
    发明授权
    Bromination 失效
    烧伤

    公开(公告)号：US5092971A

    公开(公告)日：1992-03-03

    申请号：US326109

    申请日：1989-03-20

    Applicant: Philip J. Turner ,  Martin Jeff

    Inventor： Philip J. Turner ,  Martin Jeff

    IPC: B01J19/12 ,  C07B39/00 ,  C07C17/00 ,  C07C17/14 ,  C07C22/04 ,  C07C25/02 ,  C07C25/13 ,  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 monobrominated derivative is desirable as a precursor for the selective production of, for example, the corresponding alcohols. The product can be obtained by a photolytic reaction between the substrate, hydrogen peroxide and hydrogen bromide in approximately equimolar ratios in an organic solvent, but improvement in the yield of the product coupled with similar or improved selectivity in its production was either not achieved or was actually impaired by a range of variations in the ratios and by omitting the solvent.The invention employs mole ratios of H.sub.2 O.sub.2 :substrate of 0.1:1 to 0.4:1, preferably 0.2:1 to 0.33:1 and of H.sub.2 O.sub.2 :bromide of 1:1.2 to 1:2, preferably about 1:1.3 to 1:1.8 and progressive introduction of the H.sub.2 O.sub.2, either in the presence or absence of the solvent, while irradiating with light preferably having principal emissions in the range of 250 to 600 nm, and the process thereby achieves either or both of improved yield and improved selectivity of the alpha monobrominated product. The reaction mixture is preferably maintained at 50.degree. to 70.degree. C. The process is especially suitable for deactivated alkylarenes, such as o-nitrotoluene.

    Process for producing di(aryloxy)alkane
    278.
    发明授权
    Process for producing di(aryloxy)alkane 失效
    制备二（芳氧基）烷烃的方法

    公开(公告)号：US5041604A

    公开(公告)日：1991-08-20

    申请号：US540872

    申请日：1990-06-20

    Applicant: Toranosuke Saito ,  Masakatu Kitani ,  Takashi Ishibashi

    Inventor： Toranosuke Saito ,  Masakatu Kitani ,  Takashi Ishibashi

    IPC: C07C65/21 ,  B01J23/02 ,  C07B31/00 ,  C07B41/04 ,  C07B61/00 ,  C07C41/00 ,  C07C41/01 ,  C07C41/16 ,  C07C43/20 ,  C07C45/00 ,  C07C49/84 ,  C07C51/00 ,  C07C67/00 ,  C07C201/00 ,  C07C201/12 ,  C07C205/38 ,  C07C253/00 ,  C07C253/30 ,  C07C255/37 ,  C07C255/54

    CPC classification number: C07C41/16

    Abstract: A process for producing a high quality di(aryloxy)alkane with a high yield by the use of readily commercially available materials, without using any particular solvent or agent and by means of a simple operation and a general apparatus is provided, which process comprises subjecting a halogenated alkane of the formula (II)X--A--Y (II)wherein X and Y each represent a halogen atom and A represents a lower alkylene group, and a phenol of the formula (III) ##STR1## wherein R.sub.1 to R.sub.5 each are same or different, represent hydrogen, halogen, lower alkyl, lower alkoxy, carboxylic acid salt, acyl or nitro group, and may form a ring in conjunction of two adjacent groups,to condensation reaction in the presence of an alkali in an aqueous medium to form a di(aryloxy)alkane of the formula (I) ##STR2## and is characterized (i) by carrying out the condensation reaction in a molar ratio of the compound of the formula (II): the phenol of the formula (III): the alkali in terms of monovalent base of 1:1.5 to 3.0:1.5 to 3.0; or(ii) by carrying out the condensation reaction of the above (i) and adjusting the quantity of the aqueous medium phase after completion of the reaction can be 35% or less based on the oily phase; or(iii) by carrying out the condensation reaction of the above (i), feeding at least the alkali among the reaction components with progress of the reaction and adjusting the quantity of the aqueous medium phase as described in the above (ii).

    Abstract translation: 提供了一种通过使用容易商业化的材料生产高质量的二（芳氧基）烷烃的方法，而不使用任何特定的溶剂或试剂，并且通过简单的操作和一般的设备，该方法包括 式（II）XAY（II）的卤化烷烃，其中X和Y各自表示卤素原子，A表示低级亚烷基，和式（III）的苯酚（III）其中R1至R5各自 相同或不同，表示氢，卤素，低级烷基，低级烷氧基，羧酸盐，酰基或硝基，并且可以与两个相邻基团结合形成环，在碱的存在下在水性介质中进行缩合反应 形成式（I）的二（芳氧基）烷烃（I），其特征在于（i）通过以式（II）的化合物与式（II）的苯酚的摩尔比进行缩合反应： 式（III）：以碱为一价碱 为1：1.5至3.0：1.5至3.0; 或者（ii）通过进行上述（i）的缩合反应，并且在反应完成后调整水介质相的量可以基于油相为35％以下。 或者（iii）通过进行上述（i）的缩合反应，至少将反应成分中的碱与反应进行同时进行，并且如上述（ii）所述调节水相介质相的量。

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