反应详情

Under nitrogen atmosphere, 1-(2-isocyanobenzyl)-3-methylurea (98.4 g) and cyanoacetic acid (80.0 g) was added to N,N-dimethylformamide (836 ml). The mixture was stirred at room temperature and methanesulfonyl chloride (72.8 ml) was added dropwise with stirring at this temperature. The mixture was stirred at room temperature for 4 hrs, cooled with water, and water-isopropanol [2:1 (volume ratio), 1670 ml] was added drop wise. The mixture was stirred under water-cooling for 1 hr, and the precipitated crystals were collected by filtration and dried to give 3-(2-cyano-acetyl)-3-methyl-1-(2-isocyanobenzyl)-urea with 68% yield.

1. stirringwith stirring at this temperature
2. stirringThe mixture was stirred at room temperature for 4 hrs
3. additionwas added drop wise
4. stirringThe mixture was stirred under water-
5. temperaturecooling for 1 hr
6. filtrationthe precipitated crystals were collected by filtration
7. customdried