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 minutes. Sodium triacetoxy borohydride (1.5 g; 7.11 mmole) was added portionwise over a 10 minutes 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