反应详情

A mixture of 1,664 g of 5,5-dimethyl-hydantoin (13.0 mols), 897 g of anhydrous potassium carbonate (6.5 mols), 5,148 g of 1,2-dichloroethane (52 mols) and 1,458 ml of dimethylformamide is reacted for 18 hours and 20 minutes at 90°C to 100°C internal temperature (external temperature 155°C), whilst constantly removing the resulting water of reaction by azeotropic circulatory distillation. Water of reaction eliminated: 110 g (94.0% of theory). Thereafter the reaction mixture, whilst still hot, is separated by filtration from the potassium chloride produced, the filtrate is concentrated on a rotary evaporator at 100°C under a waterpump vacuum and the residue is dried to constant weight at 100°C and 10-1 mm Hg.

1. customis reacted for 18 hours and 20 minutes at 90°C to 100°C internal temperature (external temperature 155°C)
2. customwhilst constantly removing
3. customthe resulting water of reaction
4. distillationby azeotropic circulatory distillation
5. customWater of reaction
6. customThereafter the reaction mixture, whilst still hot, is separated by filtration from the potassium chloride
7. customproduced
8. concentrationthe filtrate is concentrated on a rotary evaporator at 100°C under a waterpump vacuum
9. customthe residue is dried to constant weight at 100°C