Phosgene → 1-(1-Benzylpiperidin-4-yl)-3-phenylimidazolidin-2-one

Participants

Reaction Steps

With stirring, 15 g of phosgene are introduced at 5° to 10° C in the course of 1 hour into a suspension of 10 g of 1-benzyl-4-(2-phenylamino-1-ethylamino)-piperidine in 100 ml of toluene and 48.5 ml of 3N potassium hydroxide solution. After stirring for 2 hours at 5° to 10° C, the reaction mixture is made alkaline with 43 ml of 6N potassium hydroxide solution and brought to room temperature. After it has been stirred for a further 15 hours at room temperature, the reaction mixture is filtered with suction and the residue is recrystallised from isopropanol-methanol to yield 7.2 g of 1-(1-benzyl-4-piperidinyl)-3-phenyl-2-imidazolidinone.

Provenance & Evidence