Dimethylformamide → 1-Phenyl-3-isopropyl-2-oxo-1,2,3,4-tetrahydropyrido[2,3-d]pyrimidine

Participants

Reaction Steps

To a solution of 4.5 g of 1-phenyl-2-oxo-1,2,3,4-tetrahydropyrido[2,3-d]pyrimidine and 50 ml of dry dimethylformamide was added 1.2 g of 50% sodium hydride and the mixture was stirred for 30 minutes at room temperature, and then heated to a temperature of 90° - 100° C. To this was gradually added 1.28 g of isopropyl p-toluenesulfonate and the whole was reacted for 1 hour. After the reaction was complete, the solvent was distilled off from the mixture under reduced pressure. The residue obtained was diluted with water to produce a crude precipitate, which was collected by filtration and then dissolved in ethyl ether. Separation and purification were accomplished by applying the solution on a column of alumina, and the eluate was concentrated to give 4.1 g of 1-phenyl-3-isopropyl-2-oxo-1,2,3,4-tetrahydropyrido[2,3-d]pyrimidine as colorless prisms, melting at 164° - 165° C.

Provenance & Evidence