Dimethylformamide → 1-[1-(4-Fluorophenethyl)piperidin-4-yl]-6-formylindoline

Participants

Reaction Steps

A 2.5 M solution (50 ml) of n-butyllithium in hexane was added dropwise at −78° C. into a solution of 1-[1-(4-fluorophenethyl)piperidin-4-yl]-6-bromoindoline (40 g) in tetrahydrofuran (1 l) over 10 min. After 10 min, dimethylformamide (11.6 ml) was added thereto and the resultant mixture was warmed to room temperature. Next, a saturated aqueous solution of ammonium chloride (200 ml) and ethyl acetate (500 ml) were added thereto and the layers were separated. The organic layer was washed with brine, dried over anhydrous magnesium sulfate and concentrated under reduced pressure to give the crude title compound (37.5 g). A portion of this crude product was purified by silica gel column chromatography (ethyl acetate/ethanol system) to give the title compound as a yellow powder.

Provenance & Evidence