反应详情

200 g of 1-benzyl-4-(2-anilino-ethylamino)-piperidine and 2000 ml of toluene and 1940 ml of potassium hydroxide solution are charged into a reaction vessel. The temperature is kept between 5° and 10° C with a mixture of ice and methanol while 300 g of phosgene are introduced in the course of 3 hours. Thereafter the reaction mixture is stirred for 2 hours at room temperature. During the dropwise addition of 860 ml of potassium hydroxide, the temperature is kept below 25° C with an ice-bath. The batch is then stirred for 14 hours. The precipitated crystals are collected with suction and dried. The two-phase filtrate is separated in a separating funnel. The toluene phase is dried over 200 g of sodium sulphate, filtered and concentrated. The residue is recrystallied from 400 ml of ethanol to give the 1-(1-benzyl-4-piperidyl)-3-phenyl-imidazolidin- 2-one with a melting point of 173°-174° C.

1. additionare introduced in the course of 3 hours
2. customthe temperature is kept below 25° C with an ice-bath
3. stirringThe batch is then stirred for 14 hours
4. customThe precipitated crystals are collected with suction
5. customdried
6. customThe two-phase filtrate is separated in a separating funnel
7. dry with materialThe toluene phase is dried over 200 g of sodium sulphate
8. filtrationfiltered
9. concentrationconcentrated