2-Bromopyridine → tert-butyl (3R,5S)-3-[hydroxy(pyridin-2-yl)methyl]-5-[{[1-(4-methoxybutyl)-1H-benzimidazol-2-yl)carbonyl)(2-methylpropyl)amino)piperidine-1-carboxylate

Participants

Reaction Steps

To a solution of bromopyridine (0.058 ml) cooled to −78° C. in THF (5 ml) was added 1.6M-butyllithium hexane solution (0.33 ml) and the mixture was stirred for 30 min. A solution of tert-butyl (3R,5S)-3-formyl-5-[{[1-(4-methoxybutyl)-1H-benzimidazol-2-yl]carbonyl}(2-methylpropyl)amino]piperidine-1-carboxylate (257 mg) in THF (5 ml) was added and the mixture was stirred at −20° C. for 2 hr. The reaction mixture was poured into saturated aqueous ammonium chloride solution, and the mixture was extracted with ethyl acetate. The extract was washed with saturated brine, and dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure. The residue was subjected to silica gel column chromatography, and a fraction eluted with ethyl acetate-hexane (1:1-1:0) was concentrated under reduced pressure to give the object product (100 mg).

Provenance & Evidence