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    PRODUCTION OF 2,4-DICHLORO-3-ETHYL-6-NITROPHENOL
    221.
    发明专利
    PRODUCTION OF 2,4-DICHLORO-3-ETHYL-6-NITROPHENOL 失效

    公开(公告)号：JPH04164050A

    公开(公告)日：1992-06-09

    申请号：JP29325490

    申请日：1990-10-29

    Applicant: TAOKA CHEMICAL CO LTD

    Inventor： HORIKAWA YASUHIKO ,  YAMASHITA MASAYA ,  MORINO KAZUKI ,  KOYAMA SHINICHI ,  KIMURA OSAMU

    IPC: C07C201/10 ,  C07C205/26

    Abstract: PURPOSE:To safely produce the subject compound on an industrial scale in high purity and yield at a low cost by dropping an aqueous solution of 3,5- dichloro-4-ethyl-2-hydroxybenzene-sulfonic acid into an aqueous solution of nitric acid, thereby substituting the sulfonic acid group with nitro group. CONSTITUTION:The subject compound useful as an intermediate for cyan coupler for color photography can be produced on an industrial scale in remarkably improved safety and yield at a low cost with shortened induction period by dropping an aqueous solution of 3,5-dichloro-4-ethyl-2-hydroxybenzenesulfonic acid into an aqueous solution of nitric acid having a nitric acid concentration of preferably 2-70wt.%, thereby converting the sulfonic acid group to nitro group. The sulfonic acid is preferably produced by sulfonating 4-chloro-3- ethylphenol and further chlorinating the resultant 5-chloro-4-ethyl-2- hydroxybenzenesulfonic acid.

    PRODUCTION OF 2,4-DICHLORO-3-ETHYL-6-NITROPHENOL
    222.
    发明专利
    PRODUCTION OF 2,4-DICHLORO-3-ETHYL-6-NITROPHENOL 失效

    公开(公告)号：JPH0429966A

    公开(公告)日：1992-01-31

    申请号：JP22753590

    申请日：1990-08-28

    Applicant: TAOKA CHEMICAL CO LTD

    Inventor： KIMURA OSAMU ,  HORIKAWA YASUHIKO ,  YAMASHITA MASAYA ,  MORINO KAZUKI ,  KOYAMA SHINICHI

    IPC: B01J27/125 ,  B01J27/128 ,  C07B61/00 ,  C07C201/10 ,  C07C205/26 ,  C07C303/22 ,  C07C309/42

    Abstract: PURPOSE:To industrially and advantageously obtain the title compound in high purity and in high yield by chlorinating 5-chloro-4-ethyl-2-hydroxybenzenesulfonic acid with hydrogen chloride and hydrogen peroxide and then replacing the sulfonic acid group with nitro group using nitric acid. CONSTITUTION:5-Chloro-4-ethyl-2-hydroxybenzene sulfonic acid is chlorinated with hydrogen chloride (especially 5-38% aqueous solution of hydrochloric acid) and hydrogen peroxide (especially 5-60% H2O2 solution), preferably in a water solvent to afford 3,5-dichloro-4-ethyl-2-hydroxybenzene sulfonic acid. Then the sulfonic acid group is replaced with nitro group using nitric acid (preferably by dropwise adding an aqueous solution of the above-mentioned benzene sulfonic acid compound to an aqueous solution of nitric acid) to advantageously provide the objective compound useful as an intermediate of cyan color former for color photograph.

    PREPARATION OF LOWER NITROPARAFFINS
    226.
    发明专利
    PREPARATION OF LOWER NITROPARAFFINS 失效

    公开(公告)号：JPS56169648A

    公开(公告)日：1981-12-26

    申请号：JP7373980

    申请日：1980-06-03

    Applicant: MITSUI TOATSU CHEMICALS

    Inventor： TAKAGI USAJI ,  KASUGA TAKAHARU ,  TSUMURA RIYUUICHIROU

    IPC: B01J31/00 ,  B01J31/02 ,  C07C67/00 ,  C07C201/00 ,  C07C201/10 ,  C07C205/02

    Abstract: PURPOSE:To obtain the titled substance in high selectivity and in high yield, by reacting an inexpensive lower alkyl chloride as a raw material which is made to exist in an organic phase with an aqueous solution of an alkali metal salt of nitrous acid using a catalyst transferring between phases under mild conditions. CONSTITUTION:A 1-3C lower alkyl chloride, e.g., methyl chloride, is present directly in the absence of a solvent, or dissolved in a widely used solvent immiscible with water, e.g., petroleum ether, benzene, etc. so that it exists in the organic phase, while an alkali metal salt of nitrous acid is made into an aqueous solution and the salt is made to exist in the water phase. The both compounds are reacted using a catalyst transferring between the organic and the water phases, to give a corresponding lower nitroparaffin. Various kinds of quaternary ammonium salts, quaternary pyridinium salts, quaternary salts of pyridine homologues, quaternary phosphonium salts, etc. are used as the catalyst transferring between the phases. The reaction temperature is 5-90 deg.C, preferably 15-40 deg.C, and the reaction pressure is properly normal pressure to 5kg/cm G.

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