Ethyl 2-(hydroxymethyl)isonicotinate (iso-EhmnH) (4.84 g, 26.7 mmol) was dissolved in THF/H2O (40 mL, v:v = 1:1). KOH (4.58 g, 81.6 mmol, 3 eq.) was added as solid and the mixture stirred at 100 °C for 20 h and then cooled to r.t. The mixture was further cooled in ice-water and then HNO3 added to adjust the pH to 4–5. The solvent was removed under vacuum. The organic part in the solid mixture was then extracted twice with 400 mL of ethanol and the solvent removed. The powder contains inorganic material was added in hot isopropanol and then filtered, evaporation of iso-propanol yielded iso-hmnH2 as white powder. Yield 2.93 g, 72%[1].
[1] Armaghan M, et al. Isolation of first row transition metal–carboxylate zwitterions. RSC Advances, 2015; 5: 42978-42989.
