Potassium Acetate → hexahydro-1H-[1,4]oxazino[3,4-c][1,4]oxazin-3-ylmethyl acetate
반응식
Cl[CH2:2][C@@H:3]1[O:12][CH2:11][C@@H:6]2[CH2:7][O:8][CH2:9][CH2:10][N:5]2[CH2:4]1.[C:13]([O-:16])(=[O:15])[CH3:14].[K+]>CN(C=O)C>[C:13]([O:16][CH2:2][CH:3]1[O:12][CH2:11][CH:6]2[CH2:7][O:8][CH2:9][CH2:10][N:5]2[CH2:4]1)(=[O:15])[CH3:14]참가 물질
4
반응 조건
- 온도
- 140 °C
실험 절차
A suspension of (3R,9aS)-3-(chloromethyl)hexahydro-1H-[1,4]oxazino[3,4-c][1,4]oxazine (1.97 g, 10.3 mmol) and potassium acetate (10.1 g, 102 mmol) in DMF (20.0 mL) was stirred at 140° C. for 16 h, and then at 150° C. for another 12 h. The reaction mixture was partitioned between water (250 mL) and ethyl acetate (250 mL), the organic layer was washed with 5% lithium chloride (2×100 mL) and brine (100 mL) then dried over anhydrous sodium sulfate and concentrated in vacuo. Column chromatography (SiO2, 1:1 hexane:ethyl acetate, then 100% ethyl acetate) afforded 0.92 g (42%) of hexahydro-1H-[1,4]oxazino[3,4-c][1,4]oxazin-3-ylmethyl acetate as a yellow oil. Distinct diastereomers as described above were converted in this step to give: (3R,9aS)-hexahydro-1H-[1,4]oxazino[3,4-c][1,4]oxazin-3-ylmethyl acetate: 1H NMR (400 MHz, CDCl3): 4.18 (dd, 1H), 4.00 (m, 1H), 3.80 (dd, 1H), 3.68 (dt, 1H), 3.60 (dd, 1H), 3.46 (m, 2H), 3.22 (t, 1H), 2.64 (dd, 1H), 2.53 (m, 2H), 2.43-2.35 (m, 2H), 2.10 (s, 3H), and (3S,9aS)-hexahydro-1H-[1,4]oxazino[3,4-c][1,4]oxazin-3-ylmethyl acetate: 1H NMR (400 MHz, CDCl3): 4.09 (d, 2H), 3.90-3.82 (m, 2H), 3.75-3.64 (m, 3H), 3.27 (t, 1H), 3.18 (t, 1H), 2.69 (dd, 1H), 2.63 (m, 1H), 2.46-2.33 (m, 2H), 2.16 (t, 1H), 2.10 (s, 3H).