2-(trifluoromethyl)-1H-indole-5-carbonitrile → (2-(Trifluoromethyl)-1h-indol-5-yl)methanamine

A solution of 2-trifluoromethyl-1H-indole-5-carbonitrile (Intermediate 3, 0.16 g, 0.761 mmol) in tetrahydrofuran (5 ml) cooled in an ice-water bath, was treated with a 1M solution of borane tetrahydrofuran complex (3.05 ml, 3.05 mmol) dropwise via syringe. The reaction mixture was then left to stir under argon for 18 hrs while allowing it to warm to room temperature. The reaction mixture was then quenched with methanol (10 mL) and stirred at room temperature for 10 min. The reaction mixture was then poured onto a SCX cartridge (10 g) and washed well with methanol. The desired product was then eluted using 2M ammonia/methanol solution. Evaporation to dryness gave the title compound which was used in the next step without further purification.