Potassium Iodide → DES(6-fluoro-1,2-benzoxazole)-2,4-difluorobenzoyl risperidone

Participants

Reaction Steps

A suspension of 29.2 g (0.1116 mole) of 4-(2,4-difluoro-benzoyl)-piperidine-hydrochloride, 25.3 g (0.1117 mole) of 3-(2-chloroethyl)-6,7,8,9-tetrahydro-2-methyl-4H-pyrido[1,2-a]pyrimidin-4-one, 500 ml of acetonitrile, 19.6 g (0.2333 mole) of sodium hydrogencarbonate and 0.25 g (0.0015 mole) of potassium iodide is heated to boiling for 10 hours with stirring. The reaction mixture is cooled to room temperature, to the residue 200 ml of water are added. The mixture is stirred for 30 minutes and extracted with 200 ml of dichloromethane. The organic phase is separated, dried over magnesium sulfate, filtered and the filtrate is evaporated. The oily residue thus obtained is purified as follows:

Provenance & Evidence