反应详情

To a mixture of 2-amino-5-chlorobenzoic acid (25.3 g), acetic acid (9.0 mL), and water (650 mL) was added an aqueous solution (130 mL) of potassium cyanate (15.5 g), and the mixture was stirred at room temperature for 2 days. Sodium hydroxide (59 g) was added over 30 min. Water (100 mL) was added, and then the precipitated solids were collected by filtration. The resulting solids were suspended in water (700 mL), followed by addition of 4 M hydrochloric acid (55 mL), and then the precipitated solids were collected by filtration to obtain 6-chloroquinazoline-2,4-diol (19.1 g).

1. filtrationthe precipitated solids were collected by filtration
2. additionfollowed by addition of 4 M hydrochloric acid (55 mL)
3. filtrationthe precipitated solids were collected by filtration