Sulfuric Acid → 6-(2-methoxy-phenyl)-8-phenyl-2-phenylamino-5,8-dihydro-6H-pyrido[2,3-d]pyrimidin-7-one

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-(2,4-diphenylamino-pyrimidin-5-yl)-2-(2-dimethoxy-phenyl propionic acid methyl ester (181.8 mg, 0.40 mmol) (from Example 7b supra) was added 5% concentrated sulfuric acid in glacial acetic acid (3 mL) in one portion. The reaction mixture was heated at 110° C. for 3 hours. After cooling, the reaction mixture was diluted with ethyl acetate (100 mL) and quenched with 2 N aqueous sodium hydroxide solution. The organic layer was separated and successively washed with water (30 mL) and brine (30 mL), dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to give the crude product. The crude product was crystallized from ethyl acetate-hexanes to give 6-(2-methoxy-phenyl)-8-phenyl-2-phenylamino-5,8-dihydro-6H-pyrido[2,3-d]pyrimidin-7-one as an off-white solid. (Yield 119.4 mg, 67.2%).

Provenance & Evidence