反应详情

To a suspension at 0° C. of N-(2-amino-5-methoxyphenyl)-N-methylcarbamic acid t-butyl ester (4.2 g) and 4-(2,4-dioxothiazolidin-5-ylmethyl)phenoxyacetic acid (5.2 g) in methylene chloride (30 ml) was added triethylamine (5.1 ml) and 50% propylphosphonic acid cyclic anhydride in ethyl acetate (12.7 g) and the mixture was stirred at the same temperature for 2 hours. At the end of this time to the reaction mixture was added 5% aqueous sodium hydrogencarbonate solution and the mixture was extracted with methylene chloride. The extract was washed with water and diluted hydrochloric acid and concentrated in vacuo. To the residue was added methanol (40 ml) and the precipitated crystals were filtered to give the title compound (7.3 g, yield 85%).

1. extractionthe mixture was extracted with methylene chloride
2. washThe extract was washed with water and diluted hydrochloric acid
3. concentrationconcentrated in vacuo
4. additionTo the residue was added methanol (40 ml)
5. filtrationthe precipitated crystals were filtered