Interaction between dopamine and the [HPW12O40]2−Keggin ion–an X-ray and NMR study

•A novel phosphotungstate-dopamine complex was synthesized.•Dopamine interacts with the POM via hydrogen bonding from its ammonium group.•According to NMR analyses the complex dissociated in D2O. A novel complex between the [HPW12O40]2− Keggin ion and the biomolecule dopamine (C8H11NO2), [HPW12O40(dop)2] • 4H2O (1) was crystallized and structurally characterized by single crystal X-ray diffraction and infrared spectrometry. Dopamine interacts via hydrogen bonding between its ammonium group and a WO oxygen atom in [HPW12O40]2−. NMR analyses (1H DOSY) suggests that the [HPW12O40(dop)2] complex dissociates in D2O.