反应详情

To a suspension of NaH (60% in mineral oil, 300.0 mg, 7.50 mmol) in DMF (20 mL) was added (S)-tert-butyl 2,2-dimethyl-4-(2,2,2-trifluoro-1-hydroxyethyl)oxazolidine-3-carboxylate (1.09 g, 3.64 mmol) in DMF (20 mL) and the mixture was stirred at room temperature for 1 h. Then, benzyl bromide (0.86 mL, 7.23 mmol) was added and the mixture was stirred at room temperature overnight then quenched with ice-water, extracted with EtOAc. The organic extracts were washed with water, brine and dried over Na2SO4. Removal of the solvent gave a residue, which was purified by silica gel chromatography to give (S)-tert-butyl 4-((R)-1-(benzyloxy)-2,2,2-trifluoroethyl)-2,2-dimethyloxazolidine-3-carboxylate (1.21 g, 85%), which showed a complicated NMR spectrum because of the different rotamers. 1H NMR (400 MHz, CDCl3, δ in ppm) 7.28˜7.33 (m, 5H), 4.60˜4.85 (m, 3H), 3.93˜4.23 (m, 3H), 1.42˜1.65 (m, 15H).

1. stirringthe mixture was stirred at room temperature overnight
2. customthen quenched with ice-water
3. extractionextracted with EtOAc
4. washThe organic extracts were washed with water, brine
5. dry with materialdried over Na2SO4
6. customRemoval of the solvent
7. customgave a residue, which
8. customwas purified by silica gel chromatography