摘要 |
FIELD: industrial organic synthesis. SUBSTANCE: 2-methyl-1,4- naphthoquinone is prepared by catalytic oxidation of 2-methyl-1-naphtol or its mixture with 2,4-dimethyl-1-naphtol in two-phase system, wherein substance being oxidized is a part of water-immiscible organic solvent, whereas catalyst represents aqueous solution of molybdo-vanado-phosphoric heteropolyacid or its acid salt with transition metals (general formula in description) in concentration 0.2 to 0.45 M. Oxidation reaction is carried out under an inert gas atmosphere at 40 to 70 C. Distinguishing features of process consist in the following: incombustible solvent such as chloroform or trichloroethylene is used as organic solvent, catalyst additionally contains 10 to 20% of acetic acid, reduced form of heteropolyacid in 2-methyl-1,4- naphthoquinone synthesis stage is oxidized with hydrogen peroxide, and process is carried out with periodic removal of organic phase containing reaction product from catalyst solution. EFFECT: increased selectivity and productivity of catalyst. 2 cl, 2 tbl, 7 ex
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