Acetic Acid → N-Benzyl-3-(5-fluoro-1H-indol-3-yl)-cyclopentylamine

Participants

Reaction Steps

A mixture 3-(5-fluoro-1H-indol-3-yl)-cyclopentanone (1.0 g, 4.61 mmol), benzylamine (0.54 g, 5.05 mmol) and glacial acetic acid (0.7 mL, 1.08 mmol) were stirred at room temperature for 30 min. Sodium triacetoxyborohydride (1.5 g, 7.11 mmole) was added portionwise over a 10 min period. The reaction was stirred at room temperature for 24 hours. The reaction mixture was poured into 1 N aqueous NaOH (80 mL) and extracted with ethyl acetate (3×100 mL). The combined organic layers were washed with H2O (100 mL) and brine (100 mL), then were dried over anhydrous sodium sulfate, filtered and concentrated to give 1.5 g of a thick yellow oil. Flash chromatography on silica gel (7% 2 M NH3 in methanol/ethyl acetate) afforded 0.5 g of the cis isomer (first eluting) and 0.5 g of the trans isomer.

Provenance & Evidence