Sodium hydride → 1-Bromo-4-chloro-3-(2,2-difluoroethoxy)-2-fluorobenzene

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of 3-bromo-6-chloro-2-fluorophenol (15.4 g, 0.068 mol) in dimethylformamide (DMF; 25 mL) was slowly added to a suspension of sodium hydride (60% dispersion in mineral oil) (4.0 g, 0.10 mol) in DMF (100 mL) and the reaction mixture was stirred one hour. A solution of methanesulfonic acid 2,2-difluoroethyl ester (17.5 g, 0.109 mol) in DMF (10 mL) was slowly added. The resulting solution was heated at 70° C. for eighteen hours. The cooled solution was diluted with water (200 mL) and extracted with ethyl ether. The combined organic phases were dried and concentrated. The residual oil was purified by column chromatography (in hexanes) to give 1-bromo-4-chloro-3-(2,2-difluoroethoxy)-2-fluorobenzene (9.0 g, 0.031 mol): 1H NMR (CDCl3): δ 7.26 (m, 1H), 7.09 (m, 1H), 6.12 (tt, 1H), 4.30 (td, 2H).

Herkunft & Nachweise