Acetic Acid → 4-methoxy-2-(3-methyl-1-tosyl-1H-indol-4-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine

Participants

Reaction Steps

To a solution of 6-benzyl-4-methoxy-2-(3-methyl-1-tosyl-1H-indol-4-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine (1.1 g, 2.0 mmol) in THF (15 mL) was added water (3.75 mL) and acetic acid (0.34 mL, 5.9 mmol), then 20 mol % Pd(OH)2/carbon (50% wet) (0.86 g, 0.61 mmol) was added. The reaction mixture was placed under an atmosphere of hydrogen gas via balloon. After 1.5 hours the mixture was diluted with ethyl acetate and neutralized with saturated aqueous NaHCO3. The mixture was then filtered through a pad of Celite®. The eluent was then further diluted with ethyl acetate and brine and the layers were separated. The organic layer was dried over Na2SO4, filtered, and concentrated. The resulting residue was purified by silica gel flash chromatography (0-20% MeOH/DCM) to provide 4-methoxy-2-(3-methyl-1-tosyl-1H-indol-4-yl)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine. 1H NMR (400 MHz, DMSO-d6) δ ppm 1.91 (d, J=1.0 Hz, 3 H) 2.32 (s, 3 H) 2.68 (t, J=5.6 Hz, 2 H) 3.00 (t, J=5.7 Hz, 2 H) 3.72 (s, 2H) 3.92 (s, 3 H) 7.30-7.48 (m, 4 H) 7.65 (d, J=1.0 Hz, 1 H) 7.85 (d, J=8.3 Hz, 2 H) 8.04 (dd, J=7.3, 2.0 Hz, 1 H). MS (ESI+) m/z 449.2 (M+H)+.

Provenance & Evidence