Hydrochloric Acid → 1-{4-[(5E)-5-(5,6-difluoro-2-oxo-1,2-dihydro-3H-indol-3-ylidene)-2,2-dimethyl-2,5-dihydrofuran-3-yl]benzyl}piperidine-4-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

To a suspension of methyl 1-{4-[(5E)-5-(5,6-difluoro-2-oxo-1,2-dihydro-3H-indol-3-ylidene)-2,2-dimethyl-2,5-dihydrofuran-3-yl]benzyl}piperidine-4-carboxylate (50 mg, 0.10 mmol) in MeOH (5 mL), was added 1M NaOH (1 mL). The mixture was heated in 50° C. bath for 1 hour, poured into 50 mL of water and neutralized with 0.5M HCl to pH 7. The precipitates were filtered, washed with water, and dried in vacuo to give 1-{4-[(5E)-5-(5,6-difluoro-2-oxo-1,2-dihydro-3H-indol-3-ylidene)-2,2-dimethyl-2,5-dihydrofuran-3-yl]benzyl}piperidine-4-carboxylic acid as a yellow solid. Yield: 9 mg, 19%.

Provenance & Evidence