Catalyst for catalytic synthesis of N-methylpyrrolidine and application thereof

Abstract

The invention relates to technology for synthesizing an intermediate in the medicinal and chemical industry, in particular to a catalyst for catalytic synthesis of N-methylpyrrolidine and a synthesis method thereof. The catalyst consists of a carrier and a catalytic activity component, wherein the carrier is a gamma-Al2O3 or HZSM series molecular sieve; the catalytic activity component is a simple substance of metal M or an oxide thereof; the catalytic activity component accounts for 0.5 to 20 percent of the total weight of the catalyst; and the granular size of the catalyst is 4 to 20 meshes. The catalyst is prepared by a kneading and extruding method or a dipping method. The catalyst has the advantages of simple preparation, low price of raw materials and easy purchase; and when used the catalytic synthesis of N-methylpyrrolidine, the catalyst has the advantages of mild catalytic reaction condition, low three-wastes and no pollution, wherein the conversion rate of tetrahydrofuran is substantially kept over 80 percent and the yield of the N-methylpyrrolidine is substantially kept over 60 percent.

Description

technical field [0001] The invention relates to a synthesis technology of an intermediate N-methylpyrrolidine in the pharmaceutical and chemical industry, in particular to a catalyst for catalyzing the synthesis of N-methylpyrrolidine and its application. Background technique [0002] N-Methylpyrrolidine is an organic base widely used in medicine and chemical industry. It is mainly used in the preparation of broad-spectrum antibiotics cefepime and pamodine, and can also be used as a dye stabilizer and preservative. [0003] The preparation method of existing N-methylpyrrolidine is more, and wherein more representative has following several: the first kind is the N-methylpyrrolidone high-pressure catalytic hydrogenation method that U.S. Patent US4892959 reports, and this method is Under the catalysis of copper-chromium or chromium-aluminum, N-methylpyrrolidone and hydrogen are synthesized at 150°C-300°C and 6.9-34.5MPa under high pressure conditions, and the conversion rate ...

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Problems solved by technology

This method is carried out under high temperature and high pressure, which has high requirements on equipment, high risk, and large hydrogen demand in the reaction process, which makes the industrialization of this method more difficult.

The second method is "Chemical Intermediates", 2008, 08: (19-21), which introduces pyrrolidine and methanol on H-13X molecular sieves to catalyze the synthesis of N-methylpyrrolidine. This method is at 300 ° C, pyrrolidine When alkane:methanol=1:3, pyrrolidine is methylated to obtain N-methylpyrrolidine, and this method has many reports, and the yield is about 83% to 91%. This method synthesizes N-methylpyrrolidine The yield is high, but due to the high cost of raw material pyrrolidine, it is almost impossible to achieve industrial production

U.S. Patent US5136053 discloses this kind of cyclic ester and NH 2 R is ammoniated under the catalysis of aluminosilicate to obtain nitrogen-substituted pyrrolidine, but the reaction needs to be carried out under a certain pressure, and the ammonia ratio in the reaction is large, between 5 and 20, the increase of the ammonia ratio not only increases the production cost, but also increases the production cost. Also shortened catalyst life; The Journal of Organic Chemistry, 1994, 59 (14): 3998 ~ 4000 also mentioned in the study of 5 to 6 atom heterocyclic compound synthesis, Cr-ZSM-5 (30) catalyst can catalyze tetrahydrofuran Ammonia with methylamine to synthesize N-methylpyrrolidine, but in the process, the catalytic effect of the catalyst is not high, and the yield of the target product is only maintained at about 48%; "Journal of Qufu Normal University", 2009, 35 (1) : Introduced in 79~81 the reaction that solid superacid catalyzes tetrahydrofuran and methylamine to synthesize N-methylpyrrolidine, under the optimum technological condition, the yield of N-methylpyrrolidine is at 81.5%, but because of solid superacid The acidity is too strong, resulting in an increase in the amount of carbon deposition during the reaction, and the catalytic performance of the catalyst (catalyst life is 400h) and life are affected to a certain extent

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