Pyridine → 6-dimethylaminocarbonyl-5-methyl-2-phenyl-3-propargyl-4(3H)-pyrimidinone

Participants

Reaction Steps

To a stirred solution of 0.87 g (3.2 mmol) of crude 6-carboxy-5-methyl-2-phenyl-3-propargyl-4(3H)-pyrimidinone, 0.32 g (3.9 mmol) of dimethylamine hydrochloride and 2 mL of pyridine in 10 mL of THF was added 0.74 g (3.6 mmol) of solid N,N'-dicyclohexylcarbodiimide. The mixture was stirred at room temperature for 4 days and filtered to remove insoluble material. The filtrate was diluted with 150 mL of ethyl acetate, washed with 50 mL of 5% aqueous HCl and 50 mL of saturated aqueous sodium bicarbonate and dried over MgSO4. Removal of the solvent left 0.40 g of crude product which was purified by flash chromatography on a 30 g column of silica gel, eluted with 60, 80 and 100% ethyl acetate in hexanes to furnish 0.30 g (32%) of 6-dimethylaminocarbonyl-5-methyl-2-phenyl-3-propargyl-4(3H)-pyrimidinone (compound 19), mp 137°-140° C. 1H-NMR (CDCl3) δ 2.15(3H,s), 2.40(1H,t), 3.00(3H,s), 3.10(3H,s), 4.65(2H,d), 7.55(3H,m), 7.70(2H,m).

Provenance & Evidence