Borane → N,N-Dimethyl-2-(6-nitro-3,4-dihydroquinolin-1(2H)-yl)ethanamine

Participants

Reaction Steps

A solution of 1-(2-(dimethylamino)ethyl)-6-nitro-3,4-dihydroquinolin-2(1H)-one (1.0 g, 3.80 mmol) in 10 mL THF was cooled to 0° C. and treated with a solution of 1M borane in THF (21.5 mL, 21.50 mmol). The solution was heated at reflux for 6 hours then stirred at room temperature for 1 day. After this time, the mixture was cooled to 0° C. and quenched with methanol (5 mL). The mixture was concentrated, dissolved in methanol (20 mL), stirred at room temperature for 3 days then heated at reflux for 6 hours. The reaction was concentrated and the residue was subjected to Biotage silica gel chromatography using a gradient of 1-10% 2M NH3 in MeOH/CH2Cl2 to give a viscous oil (598 mg, 63.1%). 1H-NMR (CDCl3) δ 7.96 (dd, J=2.7, 9 Hz, 1H), 7.85 (d, J=2.1 Hz, 1H), 6.48 (d, J=9 Hz, 1H), 3.50-3.43 (m, 4H), 2.78 (t, J=6.3 Hz, 2H), 2.50 (t, J=7.5 Hz, 2H), 2.29 (t, 6H), 1.99-1.94 (m, 2H). MS (ESI): 250.2 (M+1).

Provenance & Evidence