反应详情

A suspension of 21.3 g of 1,5,5-trimethylhydantoin, 5.86 g of paraformaldehyde and 34 ml of hydrogen bromide in acetic acid (33%) was heated to 80° for 2 hrs., again treated with 7.9 ml of hydrogen bromide in acetic acid and heated for a further 2.5 hrs. The solution was cooled to 0°, diluted with 100 ml of methylene chloride and subsequently treated at 0° with 100 ml of ice-cold water. The methylene chloride phase was washed with water, dried and concentrated. The residue was crystallized from t-butyl methyl ether/hexane and the crystallizate was dried, there being obtained 30.9 g (88%) of pure 3-bromomethyl-1,5,5-trimethylhydantoin, m.p. 86-88°. IR (KBr): 1780s and 1732s (C=O).

1. temperaturewas heated to 80° for 2 hrs
2. temperatureheated for a further 2.5 hrs
3. temperatureThe solution was cooled to 0°
4. washThe methylene chloride phase was washed with water
5. customdried
6. concentrationconcentrated
7. customThe residue was crystallized from t-butyl methyl ether/hexane
8. customthe crystallizate was dried