Metformin Hydrochloride → HCID 178484382, compound

Participants

Reaction Steps

Under nitrogen protection, to a 500 mL flask were added 16.6 g (0.1 eq.) metformin hydrochloride solid and 100 mL ethanol solvent, and the reaction was stirred under mild heating until the solid was completely dissolved, then was cooled to ambient temperature. To the reaction was added 105 mL (0.105 eq.) 1N potassium hydroxide in methanol, and stirred while the reaction temperature was controlled at no more than 40° C. After 1 hr, about 150 mL solvent was removed under reduced pressure prior to slowly cool to about 10° C., then precipitation was initiated. The reaction was suction filtered, the precipitate was washed 2× by fresh ethanol, and the filtrates were combined to give the free base of metformin in ethanol.

Provenance & Evidence