Hydrochloric Acid → 5-(3-Benzyl-pyrrolidine-3-carbonyl)-1H-indole-3-carbonitrile

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Reaction Steps

A solution of HCl (1.0 M in MeOH, 8 mL) was slowly added at 0° C. to a solution of 3-benzyl-3-(3-cyano-1H-indole-5-carbonyl)-pyrrolidine-1-carboxylic acid tert-butyl ester (169 mg, 0.393 mmol) in MeOH (2 mL). The resulting pale yellow mixture was stirred at room temperature for 4 hours, then was quenched by addition of 0° C. aqueous NaOH (1.0 M). The resulting mixture was diluted with water and extracted with DCM. The combined organic extracts were dried over MgSO4, filtered and evaporated under reduced pressure. The crude was purified by flash chromatography (MeOH in DCM with 0.5% of NH4OH) to give 42 mg of 5-(3-Benzyl-pyrrolidine-3-carbonyl)-1H-indole-3-carbonitrile as a white foamy solid. This product was dissolved in DCM and a solution of HCl (1.0 M in Et2O, 1 equivalent) was added. MeOH was added and the resulting mixture was evaporated under reduced pressure. The residue was triturated with Et2O and 32 mg of 5-(3-benzyl-pyrrolidine-3-carbonyl)-1H-indole-3-carbonitrile hydrochloride was collected as a white solid; MS=330 [M+H]+.

Provenance & Evidence