反应详情

温度

20 °C

Methanesulfonic acid (3 drops) was added to a stirred solution of tetrahydropyranyl ether 160 (1.10 g, 3.2 mmol) in MeOH (30 mL) and the mixture was stirred at 20° C. for 1 h. The solvent was evaporated and the residue purified by chromatography, eluting with 5% MeOH/DCM, to give 1-oxide 161 (783 mg, 94%) as a yellow solid: mp 96-99° C.; 1H NMR δ 8.23 (s, 1H, H-9), 7.72 (s, 1H, H-5), 3.80 (t, J=6.5 Hz, 2H, CH2O), 3.25-3.33 (m, 2H, H-6, H-8), 3.02 (q, J=7.6 Hz, 2H, CH2), 2.68-2.86 (m, 3H, H-6, H-7, H-8), 1.84 (q, J=6.5 Hz, 2H, CH2), 1.43 (t, J=7.6 Hz, 3H, CH3), 1.40-1.45 (m, 1H, OH); 13C NMR δ 167.1, 153.8, 147.9, 147.6, 132.3, 122.7, 114.3, 61.5, 39.4, 39.1, 37.9, 37.5, 30.6, 12.3; HRMS (FAB+) calcd for C14H18N3O2 (MH+) m/z 260.1399, found 260.1397.

1. customThe solvent was evaporated
2. customthe residue purified by chromatography
3. washeluting with 5% MeOH/DCM