[CH3:1][O:2][C:3]1[CH:8]=[CH:7][C:6]([N+:9]([O-:11])=[O:10])=[CH:5][C:4]=1[OH:12].N1C=CN=C1.[Si:18](Cl)([C:21]([CH3:24])([CH3:23])[CH3:22])([CH3:20])[CH3:19]>CN(C=O)C>[Si:18]([O:12][C:4]1[CH:5]=[C:6]([N+:9]([O-:11])=[O:10])[CH:7]=[CH:8][C:3]=1[O:2][CH3:1])([C:21]([CH3:24])([CH3:23])[CH3:22])([CH3:20])[CH3:19]To a mixture of 2-methoxy-5-nitrophenol (1.53 g, 9.0 mmol) and imidazole (1.08 g, 15.9 mmol) in anhydrous DMF (40 mL) was added, with stirring, tert-butyldimethylsilyl chloride (2.05 g, 13.6 mmol) and the mixture was allowed to stir at room temperature for 16 h. The solvent was removed in vacuo and the residue was dissolved in 40 mL of 50% ethyl acetate in hexanes and filtered through 10 g of silica gel. The silica gel was washed with an additional 200 mL of 50% ethyl acetate in hexanes and the filtrates were combined and concentrated in vacuo to give 2.01 g of product as a tan crystalline solid. 1H NMR (CDCl3) δ 7.89 (dd, 1H, J=9.0 Hz, 2.8 Hz), 7.69 (d, 1H, J=2.8 Hz), 6.88 (d, 1H, J=9.0), 3.90 (s, 3H), 1.00 (s, 9H), 0.18 (s, 6H).
Loading…
