Reaktion #504267

Reaktionsgleichung

2-[2-(4-chloro-phenyl)-5,6-difluoro-benzoimidazol-1-yl]-2-cyclohexyl-ethanol

triphenylphosphine

carbon tetrabromide

→

desired compound

Ausbeute 9.0%

1-(2-Bromo-1-cyclohexyl-ethyl)-2-(4-chloro-phenyl)-5,6-difluoro-1H-benzoimidazole

Ausbeute 9.0%

Lösungsmittel

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeand then evaporated
2. 2
   SonstigeThe residue was purified by silica gel chromatography
3. 3
   Wascheneluting with a gradient of n-heptane:ethyl acetate (100:0 to 60:40)

Vorschrift

The solution of 0.2 g (0.51 mmol) 2-[2-(4-chloro-phenyl)-5,6-difluoro-benzoimidazol-1-yl]-2-cyclohexyl-ethanol (Ex. 1, int. c) in 3 mL dichloromethane was cooled to 0° C. and 134 mg (0.51 mmol) triphenylphosphine and 170 mg (0.51 mmol) carbon tetrabromide were added. The reaction was stirred for 48 h at rt. and then evaporated. The residue was purified by silica gel chromatography using a MPLC system (CombiFlash Companion, Isco Inc.) eluting with a gradient of n-heptane:ethyl acetate (100:0 to 60:40) to give the desired compound as white solid (9%). MS (Turbo Spray): m/z=453.0 [M+H].

Quelle