Bromination
    21.
    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

    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.

    Preparation of nitro compounds by vapor phase nitration of olefins
    23.
    发明授权
    Preparation of nitro compounds by vapor phase nitration of olefins 失效
    通过气相硝化烯烃制备硝基化合物

    公开(公告)号:US4766257A

    公开(公告)日:1988-08-23

    申请号:US849765

    申请日:1984-09-12

    CPC classification number: C07C201/06

    Abstract: A process for selectively forming nitrohydrocarbon compounds by contacting, at elevated temperature and pressure and in a homogeneous gas phase, an olefinic unsaturated compound having at least three carbon atoms with NO.sub.2 alone or in the presence of oxygen and/or water.

    Abstract translation: 通过在升高的温度和压力下,在均相气相中使具有至少三个碳原子的烯属不饱和化合物与NO 2单独或在氧和/或水的存在下接触来选择性地形成硝基烃化合物的方法。

    Process for forming nitroparaffin
    25.
    发明授权
    Process for forming nitroparaffin 失效
    形成硝基石蜡的方法

    公开(公告)号:US4476336A

    公开(公告)日:1984-10-09

    申请号:US510859

    申请日:1983-07-05

    CPC classification number: C07C201/06

    Abstract: An improved process for forming nitroparaffins by gaseous phase nitration of hydrocarbons higher than methane. The improvement comprises carrying out the nitration in the presence of a small amount of at least one carboxylic acid, preferably acetic acid.

    Abstract translation: 通过高于甲烷的烃的气相硝化形成硝基烷烃的改进方法。 该改进包括在少量至少一种羧酸(优选乙酸)存在下进行硝化。

    Process for producing nitroparaffins
    26.
    发明授权
    Process for producing nitroparaffins 失效
    生产硝酸的方法

    公开(公告)号:US3780115A

    公开(公告)日:1973-12-18

    申请号:US3780115D

    申请日:1972-10-19

    CPC classification number: C07C201/06 Y02P20/582 C07C205/02

    Abstract: THE INVENTION RELATES TO A PROCESS FOR THE PRODUCTION OF NITROPARAFFINS FROM HYDROCARBONS HIGHER THAN METHANE, BY NITRATION WITH NITROGEN PEROXIDE IN THE PRESENCE OF OXYGEN, INTRODUCED IN THE FORM OF AIR, WHEREIN THE NITRATION IS CARRIED OUT AT A PRESSURE WHICH IS BETWEEN 8 AND APPROXIMATELY 14 BARS, THE REACTANT GASES BEING PREHEATED UNDER THE REACTION PRESSURE AND INTRODUCED INTO THE REACTION ZONE BETWEEN 150 AND 330*C., THE GASEOUS EFFLUENTS ORIGINATING FROM THE NITRATION ZONE BEING SUBJECTED TO A RAPID COOLING OR QUENCHING.

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