反应详情

With vigorous stirring, a solution of 117 ml of a 20% phosgene solution in toluene is added dropwise at a reaction temperature of 5° to 10° C. to an emulsion of 10 g of 1-[2-hydroxy-3-(2-methoxyphenyloxy)-propyl]-4-(2-anilino-ethylamino)-piperidine in 60 ml of toluene and 37.5 ml of a 3 N aqueous sodium hydroxide solution over 11/4 hours. Thereafter 35.5 ml of a 6 N aqueous potassium hydroxide solution are added dropwise at the same reaction temperature in the course of half an hour. Stirring is continued for 30 minutes at 5° to 10° C. and for 20 hours at room temperature. The reaction mixture is filtered with suction and the crystalline residue is treated with toluene. Recrystallisation from isopropanol yields 1-{1-[2-hydroxy-3-(2-methoxy-phenyloxy)-propyl]-4-piperidyl}-3-phenyl-imidazolidin-2-one-hydrochloride in the form of white crystals with a melting point of 185°-187° C. The salt can be converted into the free compound for example by treatment with an aqueous sodium hydroxide solution.

1. filtrationThe reaction mixture is filtered with suction
2. additionthe crystalline residue is treated with toluene
3. customRecrystallisation from isopropanol