Water → 3,4-Dihydro-2H-pyrido(3,2-b)(1,4)oxazine

Participants

Reaction Conditions

Reaction Steps

To an ice-cold solution of 4H-pyrido[3,2-b][1,4]oxazin-3-one (5.00 g, 33.3 mmol) in THF (40 mL) was added lithium aluminum hydride (66.6 mL of a 1.0 M solution in THF, 66.6 mmol). Following the addition, the solution was heated to reflux. After 18 h, the solution was cooled to 0° C. and quenched the reaction with H2O (4 mL) followed by NaOH (4 mL, 15%) and H2O (10 mL). The resulting slurry was filtered over Celite and the filtrate concentrated to give the title compound (3.87 g, 85%) as a blue-gray powder: 1H NMR (500 MHz, DMSO-d6) δ 7.53 (dd, J=4.5, 1.0 Hz, 1H), 6.90-6.89 (m, 1H), 6.61 (br s, 1H), 6.44 (dd, J=8.0, 3.0 Hz, 1H), 4.08 (t, J=4.5 Hz, 2H), 3.39-3.36 (m, 2H); MS (ESI) m/e 137 (M+H)+.

Provenance & Evidence