反应详情

温度

90 °C

A solution of 2,4-dichlorophenyl isocyanate (47.0 g, 0.25 mol) in xylene (130 ml) is metered at room temperature into a solution of ethyl 5-fluoroanthranilate (45.2 g, 0.25 mol) in xylene (210 ml). After addition is complete, the mixture is stirred at 90° C. for 2 hours. Triethylamine (3.5 ml, 2.55 g, 0.025 mol) is metered in. The mixture is stirred at 90° C. for a further 2 hours. After cooling, the product is filtered off with suction and washed with 3×30 ml of xylene and dried. 86.9 g of ethyl N-(2,4-dichlorophenylcarbamoyl)-5-fluoroanthranilate of melting point 219° to 223° C. (decomposition) are obtained. The cyclization product 3-(2,4-dichlorophenyl)-6-fluoro-2,4(1H,3H)-quinazolinedione cannot be detected by thin-layer chromatography.

1. additionAfter addition
2. stirringThe mixture is stirred at 90° C. for a further 2 hours
3. temperatureAfter cooling
4. filtrationthe product is filtered off with suction
5. washwashed with 3×30 ml of xylene
6. customdried