Acetic Acid → 5,6,7,8-Tetrahydro-7-(phenylmethyl)pyrido(3,4-d)pyrimidin-4(3H)-one

Participants

Reaction Conditions

Reaction Steps

Part A: To a solution of sodium methoxide (25 wgt-% in methanol) (67.6 mL, 296 mmol) and methanol (70 mL) at 25° C. was added formamidine acetate (11.00 g, 106 mmol) and then ethyl N-benzyl-3-oxo-4-piperidine carboxylate hydrochloride (25.16 g, 84 mmol). The resulting mixture was stirred at 25° C. for 20 h. The mixture was cooled to 0° C. Water (90 mL) was added, followed by the dropwise addition of acetic acid (6.05 mL, 106 mmol), and the reaction mixture was stirred at 25° C. for another 3 h. The mixture was reduced in volume under vacuum until most of the methanol had been removed. The suspension was filtered. The solids were washed with water and then dried under vacuum to afford 7-benzyl-5,6,7,8-tetrahydropyrido[3,4-d]pyrimidin-4(3H)-one (16.10 g, 79%) as an off-white solid; Mass Spec.: m/e: 242.06 (M+H)+ [calc'd: 242.12]; 1H NMR (500 MHz, CDCl3) δ 12.61 (br s, 1H), 7.99 (s, 1H), 7.38-7.26 (m, 5H), 3.73 (m, 2H), 3.50 (m, 2H), 2.74 (m, 2H), 2.66 (m, 2H).

Provenance & Evidence