Metformin Hydrochloride → HCID 178484382, compound

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.

1. temperatureunder mild heating until the solid
2. dissolutionwas completely dissolved
3. stirringstirred while the reaction temperature
4. customwas controlled at no more than 40° C
5. customabout 150 mL solvent was removed under reduced pressure
6. temperatureto slowly cool to about 10° C.
7. customprecipitation
8. filtrationfiltered
9. washthe precipitate was washed 2× by fresh ethanol

ORD record

ord-8ada56e080cb4077a9f7be7c339f8b56

Source dataset

uspto-grants-2012_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08329710B2