反应详情

To a mixture of 2-methyl-2-(4-nitro-phenyl)-propan-1-ol (as prepared in the previous step, 1.50 g, 7.68 mmol) and t-butyl-dimethylsilyl chloride (1.51 g, 9.99 mmol) in 60 mL of DCM was slowly added imidazole (3.09 g, 45.4 mmol). After stirring at RT for 16 h, the mixture was treated with 40 mL of DCM and washed with H2O (30 mL), 15% aqueous citric acid (30 mL) and brine (20 mL). The organic layer was dried (Na2SO4) and concentrated in vacuo. The residue was purified by flash chromatography on silica gel (0-5% EtOAc/hexane) to give 1.82 g (65%) of the title compound as a light brown oil. 1H-NMR (CDCl3; 400 MHz): δ 7.85 (d, 2H, J=8.8 Hz), 7.52 (d, 2H, J=8.8 Hz), 3.59 (s, 2H), 1.35 (s, 6H), 0.86 (s, 9H), −0.04 (s, 6H).

1. washwashed with H2O (30 mL), 15% aqueous citric acid (30 mL) and brine (20 mL)
2. dry with materialThe organic layer was dried (Na2SO4)
3. concentrationconcentrated in vacuo
4. customThe residue was purified by flash chromatography on silica gel (0-5% EtOAc/hexane)