Acetic Anhydride → HCID 22612687, compound

Participants

Reaction Steps

1.5 g (3.6 mmol) of 4-(4′-trifluoromethoxy-4-biphenylyl)-2-(2,6-difluorophenyl)-4,5-dihydro-1H-imidazole (for example from Example V-1) were dissolved in 20 ml of toluene, admixed with 1.7 ml (1.84 g; 18 mmol) of acetic anhydride and boiled under reflux for 1 h. The mixture was then concentrated and the residue was recrystallized from a mixture of cyclohexane and ethyl acetate. This gave 1.07 g (65% of theory) of 1-acetyl-4-(4′-trifluoromethoxy-4-biphenylyl)-2-(2,6-difluorophenyl)-4,5-dihydro-1H-imidazole (I-7a). 0.6 g of concentration residue from the mother liquor was separated by column chromatography (silica gel; Ø=3cm, 1=30 cm; cyclohexane:ethyl acetate=5:1). 0.12 g (7% of theory) of 3-acetyl4-(4′-trifluoromethoxy-4-biphenylyl)-2-(2,6-difluorophenyl)-4,5-dihydro-3H-imidazole (I-7b) was obtained as second fraction as an oil.

Provenance & Evidence