Sulfuric Acid → 6-(4-methoxy-phenyl)-8-phenyl-2-phenylamino-5,8-dihydro-6H-pyrido[2,3-d]pyrimidin-7-one

Participants

Reaction Conditions

Reaction Steps

To the solution of 3-(2,4-diphenylamino-pyrimidin-5-yl)-2-(4-methoxy-phenyl)-propionic acid methyl ester (227.3 mg, 0.5 mmol) (from Example 1e supra) in glacial acetic acid (15 mL) was added concentrated sulfuric acid (0.2 mL) in one portion. The reaction mixture was heated at 80° C. overnight. The reaction mixture was then diluted with ethyl acetate (50 mL) and quenched with 2 N aqueous sodium hydroxide solution. The organic layer was separated and successively washed with water (10 mL) and brine (10 mL), dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to give the crude products which was crystallized from ethyl acetate-hexanes to give 6-(4-methoxy-phenyl)-8-phenyl-2-phenylamino-5,8-dihydro-6H-pyrido[2,3-d]pyrimidin-7-one as brown crystalline solid. (Yield 174.2 mg, 82.4%).

Provenance & Evidence