Potassium Iodide → 1-[4-(1,1-dimethylethyl)phenyl]-4-[4-[[1-[(4-fluorophenyl)methyl]-1H-benzimidazol-2-yl]carbonyl]-1-piperidinyl]-1-butanone

Participants

Reaction Steps

[1-[(4-fluorophenyl)methyl]-1H-benzimidazol-2-yl]-4-piperidinylmethanone mono (trifluoroacetate) (5.0 g, 11 mmol), 4-chloro-4'-tert-butylbutyrophenone (6.2, 26 mmol), potassium bicarbonate (2.5 g, 25 mmol), and potassium iodide (catalytic amount) were combined and refluxed in toluene (50 ml) and water (5 ml) for 3 days. The cooled layers were separated and the aqueous layer was extracted with ethyl acetate. The combined organic layers were washed with water, brine, dried (MgSO4), and concentrated. The resulting oil was chromatographed on silica gel (75×160 mm), eluting with ethyl acetate. The appropriate fractions were combined, concentrated, and the resulting oil crystallized from cyclohexane to afford 1-[4-(1,1-dimethylethyl)phenyl]-4-[4-[[1-[(4-fluorophenyl)methyl]-1H-benzimidazol -2-yl]carbonyl]-1-piperidinyl]-1-butanone: 3.4 g (57%), m.p. 105-106° C.

Provenance & Evidence