Stannous chloride dihydrate → HCID 58851268, compound

Participants

Reaction Conditions

Reaction Steps

To a suspension of 6-aminoquinolin-2(1H)-one (0.72 g, 4.5 mmol, see Example A41) in conc. HCl (5 mL) was slowly added NaNO2 (0.43 g, 6.3 mmol) solution in H2O (5 mL) at 0° C. After stirring for 1 h, SnCl2.2H2O (2.0 g, 9.0 mmol), dissolved in conc. HCl (7 mL), was slowly added at such a rate that the temperature of the mixture did not rise above 5° C., After stirring for 2 h, the resultant solid was filtered, dried, and suspended in EtOH. To this were added 3-cyclopentyl-3-oxopropanenitrile (0.68 g, 4.9 mmol) and a few drops of HCl and the mixture was heated at 80° C. for 16 h. The solution was concentrated, dissolved in satd. NaHCO3 solution and the product was extracted with EtOAc (2×30 mL). The combined organic extracts were washed with brine, dried (Na2SO4), concentrated and the resultant solid triturated with toluene (10 mL) and filtered to yield 6-(5-amino-3-cyclopentyl-1H-pyrazol-1-yl)quinolin-2(1H)-one (0.75 g, 57% yield) as a solid. 1H NMR (400 MHz, DMSO-d6): δ 7.95 (d, J=10.0 Hz, 1H), 7.81 (d, J=2.4 Hz, 1H), 7.68 (dd, J=8.8 Hz, 2.0 Hz, 1H), 7.35 (d, J=8.8 Hz, 1H), 6.54 (d, J=8.8 Hz, 1H), 5.32 (s, 1H), 5.24 (brs, 2H), 2.92-2.84 (m, 1H), 1.94-1.86 (m, 2H), 1.73-1.57 (m, 6H); MS (ESI) m/z: 295.2 (M+H+).

Provenance & Evidence