Methyl iodide → 1-Methylpiperidine-4-carboxylic acid

Participants

Reaction Steps

A mixture of ethyl piperidine-4-carboxylate (4.72 g), methyl iodide (2.24 mL), potassium carbonate (8.29 g) and acetonitrile (50 mL) was stirred at room temperature for 2 hrs. The reaction solution was concentrated under reduced pressure, and water (150 mL) was added thereto, followed by extracting with ethyl acetate (150 mL). The ethyl acetate layer was washed with saturated brine (100 mL), and dried over anhydrous magnesium sulfate, then concentrated under reduced pressure. To the residue (2.64 g) was added 1 N aqueous solution of sodium hydroxide (20 mL), and stirred at room temperature overnight. To the reaction solution was added 1 N hydrochloric acid (20 mL) to neutralize, and concentrated under reduced pressure. To the residue was added ethanol, and the precipitate was filtered off, and the filtrate was concentrated under reduced pressure. After repeating this operation again, to the residue were added ethanol and ethyl acetate to crystallize, which gave 1-methylpiperidine-4-carboxylic acid as colorless solid (1.79 g).

Provenance & Evidence