METHOD FOR SELECTIVE PRODUCTION OF N-METHYL-PARA-ANISIDINE Russian patent published in 2014 - IPC C07C217/84 C07C213/08 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing N-methyl-para-anisidine by N-alkylation of para-anisidine with methanol in vapour phase in the presence of dehydrogenating catalysts at temperature of 180-260°C and atmospheric pressure, followed by separation of products by rectification. The process is carried out in a nitrogen or hydrogen current. The catalysts used can be catalysts having the following composition: CuO - 55%; ZnO - 10.5%; Cr₂O₃ - 13.5%; Al₂O₃ - the balance, or CuO - 25%; ZnO - 25%; CaO - 5%; Al₂O₃ - the balance, or CuO - 25-45%; BaO - 2-10%; TiO₃ - 15-35%; Cr₂O₃ - the balance, or CuO - 35-45%; ZnO - 25-35%; NiO - 3-8%; Al₂O₃ - the balance, or CuO - 12-19% MnO - 2-3%; Cr₂O₃ - 1.0-1.4%; Fe₂O₃ - 1.0-1.4%; Co₃O₄ - 0.5-0.8%; Al₂O₃ - the balance. The catalysts used can also be Raney nickel or BASF Cu-E403TR catalyst with the composition: copper chromite 67-71%, copper 11-15%, copper oxide 8-21%, graphite 0-4%, chromium oxide (3+) 0-3%; or a BASF Cu-0203T 1/8 catalyst with the composition: copper oxide 75-100%, chromium oxide (3+) 0.1-1%, or BASF Cu-E406 TR, having the composition: Cu - 36%, Cr - 31%, Ba - 6%. The process is carried out primarily in the presence of triethylamine.

EFFECT: method enables to use existing industrial plants used to produce aniline and N-methylaniline and obtain N-methyl-para-anisidine of high purity and high output; the method is suitable for large-scale production.

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