Imidazole → (4-Bromophenoxy)(tert-butyl)dimethylsilane

Participants

Reaction Steps

To a stirred solution of p-bromophenol (30 g, 0.1734 mol) in 1, 2-dichloroethane (300 mL) at 23° C. was added imidazole (29.45 g, 0.433 mol). After 15 min, tert-butyldimethylsilylchloride (28.75 g, 0.190 mol) was added, and the resulting solution heated at reflux for 3 h. The mixture was cooled to room temperature and poured onto saturated aqueous NH4Cl and extracted with CH2Cl2 (3×200 mL). The combined extracts were washed with brine (200 mL), dried (NaSO4), filtered and evaporated in vacuo. The crude product was distilled via short-path distillation (0.5 mm Hg, 130° C.) to give (4-bromo-phenoxy)-tert-butyl-dimethylsilane (49.6 g, 99.5% yield) as a colorless oil. Rf=0.80 (1:3 EtOAc/hexanes). IR (thin film) 3390, 2951, 2928, 1584, 1479, 1250 cm−1. 1H NMR (300 MHz, CDCl3) δ 7.34 (1H, d, J=9 Hz), 6.74 (1H, d, J=9 Hz), 1.00 (12H, s), 0.21 (6H, s). 13C NMR (75 MHz, CDCl3) δ 154.76, 132.22, 121.83, 113.55, 25.58, 18.12, −4.54. HRMS calcd. for C12H20BrOSi (MH+) 287.0461, found 287.0463.

Provenance & Evidence