Hydrochloric Acid → Isopilocarpic Acid Sodium Salt

Participants

Reaction Conditions

Reaction Steps

Pilocarpine hydrochloride (3.92 g; 16.00 moles) was dissolved in distilled water (4 ml) and the solution was cooled to about 0° C. To the solution 18 ml of ice cold 2M NaOH were added in four portions. The solution was left standing at about 0° C. for one hour. After neutralizing excess NaOH with 5 ml of 1M HCl, the solution was evaporated under reduced pressure. The residue was dissolved in 60 ml of absolute ethanol and mixed for 10 minutes at 60° C. After cooling to 4° C. undissolved NaCl was removed by filtration. The filtrate was evaporated under reduced pressure, whereby 3.93 g of sodium pilocarpate were obtained as a white, extremely hygroscopic substance.

Provenance & Evidence