Toluene-2,4-bisurea (2,4-TBU), which could be used in preparation of toluene-2,4-dicarbamate ( TDI), was synthesized from toluene diisocynate and ammonia with acetone as the solvent. The synthesized products 2,4-TBU and toluene-2,6-bisurea(2,6-TBU) which was the isomer of 2,4-TBU were separated. The synthesized 2,4-TBU was characterized by means of melting point determination, thin-layer chromatography, FTIR, NMR and elemental analysis. A high performance liquid chromatography (HPLC) method with the external standard method was established to analyze 2, 4-TBU quantitatively. The results showed a good linear relationship of the peak area with the sample concentration in the 2,4-TBU concentration range of 3.0 - 12.0 mg/L, and the 2,4-TBU recovery and the relative standard deviation reached 99. 0% - 100. 5% and less than 0. 98% , respectively. In this synthesis reactions, TDI transfirmed completely. The yield of 2,4-TBU and 2,6-TBU were 80% and 20% , respectively.%以甲苯二异氰酸酯(TDI)和氨气为原料、丙酮为溶剂,合成了1-甲基-2,4-苯二脲(2,4 -TBU),并建立了其与副产物1 -甲基-2,6-苯二脲(2,6- TBU)两种同分异构体的分离方法；采用熔点测定、薄层色谱、FTIR、NMR和元素分析等方法对2,4 -TBU的结构进行了表征；在高效液相色谱分析中,采用外标法建立了2,4- TBU的定量分析方法.测得2,4- TBU的质量浓度在3.0～12.0 mg/L内与峰面积呈现良好的线性关系,回收率为99.0％～100.5％,相对标准偏差小于等于0.98％；该合成反应中,TDI完全转化,2,4- TBU和2,6- TBU的收率分别为80％和20％.建立了2,4-TBU定量分析方法,该方法操作简单、灵敏度高、准确性和重复性好,为尿素法合成甲苯-2,4-二氨基甲酸甲酯的研究奠定了基础.
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