Acetic Acid → HCID 52914257, compound

Participants

Reaction Steps

2-(6,9-Difluoro-3-oxo-5-{[4-(1H-pyrazol-1-yl)phenyl]methyl}-3,5-dihydro-2H-pyrazolo[4,3-c]quinolin-2-yl)benzaldehyde [(Example 39) 15 mg, 0.031 mmol] was suspended in acetonitrile (1.5 mL), treated with ethylamine (0.15 mL, 0.15 mmol, 1.0 M tetrahydrofuran solution, 5 equiv), acetic acid (10 μL, 0.17 mmol, 5.6 equiv) and powdered 4 Å molecular sieves (15 mg, 1 wt equiv) and stirred for 30 minutes at ambient temperature. Sodium triacetoxyborohydride (6.6 mg, 0.031 mmol, 1 equiv) was added and the mixture was stirred for 3 hours at ambient temperature. The mixture was diluted with dichloromethane (5 mL), filtered and concentrated in vacuo. The residue was diluted with dimethylsulfoxide (1 mL) and water (0.1 mL) and treated with 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ, 7.0 mg, 0.031 mmol, 1 equiv). After stirring for 30 minutes, the mixture was filtered and purified by preparative reverse phase HPLC (5:95 to 95:5; water containing 0.1% trifluoroacetic acid:acetonitrile containing 0.1% trifluoroacetic acid:acetonitrile), providing the titled compound: 1H-NMR (400 MHz, d6-DMSO) δ 9.24 (1H, s), 8.80 (2H, br s), 8.47 (1H, d, J=2.5 Hz), 7.82 (2H, d, J=8.7 Hz), 7.73-7.68 (3H, m), 7.64-7.58 (2H, m), 7.55-7.50 (2H, m), 7.35 (2H, d, J=8.6 Hz), 6.54 (1H, dd, J=2.4, 1.9 Hz), 5.86 (2H, d, J=3.2 Hz), 4.16 (2H, br m), 2.97-2.92 (2H, m), 0.91 (3H, t, J=7.5 Hz) ppm; high resolution mass spectrometry (ES+) m/z 511.2035 [(M+H)+; calculated for C29H25F2N6O: 511.2053].

Provenance & Evidence