| 摘要 |
industrial organic synthesis. SUBSTANCE: alpha-tocopherol precursor 2,3,5- trimethyl-1,4-bezoquinone is prepared by catalytic oxidation of 2,3,6- trimethylphenol by oxygen or oxygen-containing compounds using catalytic system consisting of aqueous solution of molybdenum-vanadium-phosphoric heteropolyacid or mixture of heteropolyacids and/or their salts described by general formula HaPxMoyV2Ob or its acid salts where , and a= 2b-6y-5(x+z). Concentration of vanadium in solution of heteropolyacid or its salt is not below 1.6 g-atom/l. 2,3,6-trimethylphenol is used in the form of solution in normal primary alcohol containing at least 5 carbon atoms or in mixture of such alcohols. Oxidation reaction is conducted in the temperature range 15 <= t <= 70°C in periodical mode at manometrically measured partial oxygen pressures 0 <= Po<= 1,3 atm or in quasi-continuous mode at pressures 1,3 < Po<= 20. Catalytic systems are characterized by high selectivity (>96%), high activity, and high purity of product, which is essentially free of impurities and is fit to be processed with no further purification. EFFECT: considerably simplified operation of separation of catalyst from reaction products and simplified equipment. 7 cl, 1 dwg, 3 tbl, 35 ex
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