tert-butyl 5-phenyl-2H-1,4-oxazine-4(3H)-carboxylate → Tert-butyl 3-phenylmorpholine-4-carboxylate

Participants

Reaction Steps

Tert-butyl 5-phenyl-2H-1,4-oxazine-4(3H)-carboxylate (170 mg, 0.65 mmol) was dissolved in methanol (10 ml). 10% Pd/c (100 mg) was added and the mixture stirred under hydrogen for 18 hours. The catalyst was removed by filtration and the filtrate concentrated to give crude tert-butyl 3-phenylmorpholine-4-carboxylate. The crude product was dissolved in DCM (10 ml) and TFA (1 ml) was added. The mixture was stirred at room temperature for 4 hours. The mixture was then concentrated and the crude purified by reverse phase HPLC (90/10 acetonitrile/water). The subtitle compound was obtained as a white solid (130 mg, 73%); 1H-NMR (d6-DMSO) 3.26 (2H, brm), 3.72-3.81 (2H, m), 4.00-4.03 (2H, m), 4.49 (1H, m), 7.45-7.53 (5H, m), 9.27 (2H, brs); 13C-NMR (d6-DMSO) 43.5, 57.7, 62.8, 68.2, 127.7, 128.9, 129.3; MS ES(+) 164.1 (M++1); HRMS m/z calcd for C10H13NO+H+ 164.1075 [M+H+]. Found 164.1082. IR λmax=1659 cm−1.

Provenance & Evidence