Acetic Acid → HCID 68154602, compound

Participants

Reaction Steps

2-(3-Oxo-5-{[4-(1H-pyrazol-1-yl)phenyl]methyl}-3,5-dihydro-2H-pyrazolo[4,3-c]quinolin-2-yl)benzaldehyde (Example 529, 0.15 g, 035 mmol) and pyrrolidine (0.031 mL, 0.38 mmol, 1.1 equiv) were combined in 1,2-dichloroethane (2 mL) and treated with powdered 4 Å molecular sieves (0.15 g, 1 wt equiv) and acetic acid (0.099 mL, 1.7 mmol, 5 equiv). After stirring vigorously for 20 minutes at ambient temperature, the mixture was treated with sodium triacetoxyborohydride (0.11 g, 0.52 mmol, 1.5 equiv) portionwise over 2 minutes. After stirring for 90 minutes, the mixture was treated with sodium bicarbonate (7 mL, aqueous saturated) and stirred for 5 minutes. The mixture was diluted with chloroform (20 mL), filtered and the organic filtrate was washed once with sodium bicarbonate (10 mL, aqueous saturated) and brine (10 mL), dried with sodium sulfate, filtered and concentrated in vacuo. The residue was purified by silica gel gradient chromatography (100:0 to 90:10; chloroform:methanol; then 92:8; chloroform:methanol containing 10% ammonium hydroxide), providing the titled compound: 1H-NMR (400 MHz, d6-DMSO) δ 9.12 (1H, br s), 8.46 (1H, dd, J=2.5, 0.4 Hz), 8.32 (1H, s), 8.20 (1H, d, J=8.1 Hz), 7.84 (2H, d, J=8.8 Hz), 7.78 (1H, d, J=8.3 Hz), 7.73 (1H, d, J=1.7 Hz). 7.65-7.60 (2H, m), 7.53 (1H, t, J=7.4 Hz), 7.48 (2H, d, J=8.6 Hz), 7.45-7.33 (2H, m), 6.53 (1H, dd, J=2.5, 1.8 Hz), 5.77 (2H, s), 3.63 (2H, br m), 2.36 (4H, br m), 1.63 (4H, br m) ppm; low resolution mass spectrometry (ES+) m/z 501.0 [(M+H)+; calculated for C31H29N6O: 501.2].

Provenance & Evidence