Piperidine → 2,6-Dimethyl-1-oxo-4-(piperidin-1-yl)-1lambda~5~-pyrimidine

Participants

Reaction Steps

100 ml of piperidine are introduced into a 250 ml three-necked flask fitted with a thermometer, a condenser and a magnetic stirrer and 13.5 g (8.51×10-2 mol) of 2,4-dimethyl-6-chloropyrimidine 3-oxide are then added, in solid portions, in a manner such that exothermic heat does not develop beyond 60° C. The reaction mixture is then allowed to return to ambient temperature; the piperidinium hydrochloride is then removed from the mixture by filtration and the filtrate is evaporated to dryness. The crude oil obtained crystallises rapidly at ambient temperature. The crystalline mass is dissolved in a minimum of ethanol and ethyl ether is then added cold until precipitation occurs. The mixture is stirred for half an hour and the precipitate is then filtered off and drained. A final filtration through silica gel using the dichloromethane/methanol (90/10) eluent system allows white crystals to be obtained.

Provenance & Evidence