... DOI: 10.1039/B719766G (Paper) Dalton Trans., 2008, 2054-2060 ... mg, 0.27 mmol) in methanol (3.5 mL) was added 2,2′-bipyridine-5,5′-dicarboxylic acid (66 mg, 0.27 mmol) and the mixture was stirred at ambient temperature for 5 min before heating at reflux for 15 min. ...