C(Cl)Cl.Cl.[Br:5][C:6]1[CH:7]=[N:8][CH:9]=[C:10]([CH2:12][OH:13])[CH:11]=1.C(N(CC)CC)C.[Si:21](Cl)([C:24]([CH3:27])([CH3:26])[CH3:25])([CH3:23])[CH3:22]>C(OCC)C>[Br:5][C:6]1[CH:7]=[N:8][CH:9]=[C:10]([CH2:12][O:13][Si:21]([C:24]([CH3:27])([CH3:26])[CH3:25])([CH3:23])[CH3:22])[CH:11]=1
To a methylene chloride solution (20 mL) of 3-bromo-5-(hydroxymethyl)pyridine hydrochloride (described in example 69a) (1.00 g, 4.48 mmol) under nitrogen was added triethylamine (2.50 mL, 17.9 mmol, 4 eq) and tert-butyldimethylsilyl chloride (0.75 g, 5.0 mmol, 1.1 eq). The resulting solution was heated to reflux for 18 h, cooled to room temperature and diluted with diethyl ether (200 mL). The organic phase was washed with 2.5N NaOH (1×100 mL), water (3×100 mL) and saturated brine (1×100 mL). The ether solution was dried over anhydrous magnesium sulfate, filtered, and reduced to an colorless oil. The procedure resulted in 1.10 g (81%) of the title compound. The product required no additional purification. TLC analysis (Rf 0.19, ethyl acetate) MS (CI, CH4) m/z 302 (M+1,100), 304 (96), 330 (M+29,4), 332 (4)
Wird geladen…
