Lithium borohydride → 1-(1-hydroxypropan-2-yl)-2-methyl-4-(trifluoromethyl)-1H-indole-5-carbonitrile

Beteiligte Stoffe

Reaktionsschritte

To an ice-cold solution of methyl 2-(5-cyano-2-methyl-4-(trifluoromethyl)-1H-indol-1-yl)propanoate (Example 1) (0.263 g, 0.848 mmol) in THF (5 mL) was added dropwise LiBH4 (2M in THF) (1.695 mL, 3.39 mmol). After complete addition of the reducing agent, the cold bath was removed and the mixture was stirred at rt. After 2 h, the reaction mixture was cooled in an ice bath and a saturated aqueous NH4Cl solution (15 mL) was added slowly. The mixture was then diluted with EtOAc (40 mL) and treated slowly with 1N HCl (10 mL). The phases were separated and the aqueous phase was washed with EtOAc (20 mL). The combined organic phases were washed with brine, dried over Na2SO4, filtered and concentrated. The residue was chromatographed over silica gel using a 20-60% EtOAc-hexane gradient to give 1-(1-hydroxypropan-2-yl)-2-methyl-4-(trifluoromethyl)-1H-indole-5-carbonitrile (0.212 g, 83% yield) as a white solid: MS (ESI): m/z 283 (MH+).

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