p-Toluenesulfonic acid → 5,7-dimethoxy-2-(pyridin-2-yl)quinazolin-4(3H)-one

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-amino-4,6-dimethoxybenzamide (0.15 g, 0.764 mmol) in N,N-dimethyl acetamide (5 mL) were added 2-pyridine carboxaldehyde (0.082 g, 0.764 mmol), sodium hydrogen sulphite (58.5%, 0.15 g, 0.84 mmol), and p-toluenesulfonic acid (15 mg, 0.0764 mmol). The reaction mixture was stirred at 150° C. overnight. The mixture was cooled to room temperature. Water (40 mL) was added and the reaction mixture was extracted with dichloromethane (2×50 mL). The combined organic layers were washed with water and dried over anhydrous Na2SO4. The solvent was removed and the crude compound was purified by column chromatography (silica gel 230-400 mesh; 1% methanol in CH2Cl2 as eluent) to give 5,7-dimethoxy-2-(pyridin-2-yl)quinazolin-4(3H)-one (0.077 g, 36%) as a white solid. 5,7-dimethoxy-2-(pyridin-2-yl)quinazolin-4(3H)-one was converted to the corresponding hydrochloride. Selected data: MS (m/z): 284.0; MP 215-217° C. (hydrochloride).

Provenance & Evidence