Acetic Acid → 2-(2,6-Dimethylphenyl)-4-(3-methoxypropoxy)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine

Participants

Reaction Steps

To a solution of 6-benzyl-2-(2,6-dimethylphenyl)-4-(3-methoxypropoxy)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine (170 mg, 0.41 mmol) in THF (3.5 mL) was added water (0.5 mL) and acetic acid (0.070 mL, 1.22 mmol). The reaction mixture was placed under argon and then charged with 20 mol % Pd(OH)2/C (50% wet, 114 mg, 0.081 mmol). The atmosphere was then replaced with hydrogen gas via a balloon and was permitted to stir for 5 hours. The mixture was then neutralized with saturated aqueous sodium bicarbonate, diluted with dichloromethane and filtered through a pad of Celite®. The eluent was further diluted with dichloromethane and saturated aqueous sodium bicarbonate and the layers were separated. The aqueous layer was extracted two additional times with dichloromethane. The organic layers were combined, dried over Na2SO4, filtered and concentrated. The resulting residue was purified by silica gel flash chromatography [7-20% (2 M NH3 in MeOH)/DCM] to furnish 2-(2,6-dimethylphenyl)-4-(3-methoxypropoxy)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine. MS (ESI+) m/z 328.3 (M+H)+.

Provenance & Evidence