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[目的]N-(2-甲基)苯基羟胺是一种重要农药中间体,用选择性还原方法进行合成。[方法]以邻硝基甲苯为主要原料,经Raney Ni-水合肼还原制备N-(2-甲基)苯基羟胺。[结果]在优化的反应条件下,N-(2-甲基)苯基羟胺的反应收率为78.5%。加入适量SiO~2颗粒后,反应收率可达90.2%。补加适量催化剂后,Raney Ni可套用1次。由于N-(2-甲基苯基)羟胺在空气中不稳定,尝试了进一步与氯甲酸甲酯反应制备N-羟基-N-2-甲苯氨基甲酸甲酯,2步总收率85.7%(含量为98.2%),其结构经氢谱核磁分析确证。[结论]N-(2-甲基)苯基羟胺合成工艺具有生产成本低、收率高和易于工业化生产等优点。
[Objective] N- (2-methyl) phenylhydroxylamine is an important pesticide intermediate synthesized by selective reduction method. [Method] With o-nitrotoluene as the main raw material, N- (2-methyl) phenylhydroxylamine was prepared by reduction with Raney Ni-hydrazine hydrate. [Result] Under the optimized reaction conditions, the reaction yield of N- (2-methyl) phenylhydroxylamine was 78.5%. After adding appropriate amount of SiO 2 particles, the reaction yield can reach 90.2%. After adding a suitable amount of catalyst, Raney Ni can be applied once. Due to the instability of N- (2-methylphenyl) hydroxylamine in the air, an attempt was made to further react with methyl chloroformate to prepare methyl N-hydroxy-N-2-methylphenylcarbamate in 2 steps in a total yield of 85.7% Content of 98.2%), its structure confirmed by nuclear magnetic resonance spectroscopy. [Conclusion] The synthesis of N- (2-methyl) phenylhydroxylamine has the advantages of low production cost, high yield and easy industrialization.