反应详情

A mixture of ethyl 2-[3-(4-bromo-2-fluorobenzyl)-7-chloro-1,2,3,4-tetrahydro-2,4-dioxoquinazolin-1-yl]-acetate (249 g) and 1N aqueous sodium hydroxide (795 ml) in methanol (1.6 l) was refluxed for 30 minutes with stirring. The solvent was evaporated and the residue was dissolved in hot water (5 l). The aqueous solution was poured into ice-cold 0.5N hydrochloric acid (3 l). The precipitates were collected by filtration and recrystallized from a mixture of ethanol (6 l) and water (3 l) to give 2-[3-(4-bromo-2-fluorobenzyl)-7-chloro-1,2,3,4-tetrahydro-2,4-dioxoquinazolin-1-yl]-acetic acid (198 g).

1. temperaturewas refluxed for 30 minutes
2. customThe solvent was evaporated
3. dissolutionthe residue was dissolved in hot water (5 l)
4. additionThe aqueous solution was poured into ice-cold 0.5N hydrochloric acid (3 l)
5. filtrationThe precipitates were collected by filtration
6. customrecrystallized from a mixture of ethanol (6 l) and water (3 l)