Metformin synthesis patents #KaniFound this patent http://www.google.co.uk/patents/WO2010146604A2?cl=enLooks very worth pursuing. Essentially a reflux in toluene followed by solvent extraction, collecting the aqueous layer.
Found this patent http://www.google.co.uk/patents/WO2010146604A2?cl=enLooks very worth pursuing. Essentially a reflux in toluene followed by solvent extraction, collecting the aqueous layer.