Intracomplex π-stacking interactions between three adjacent molecules of phosphoryl-containing 1,8-naphthyridine (L) in lanthanide(III) complexes [LnL3]3+: Crystal structures, DFT calculations, and solution study by electrospray ionization mass spectromet

The crystal structure of novel complex [LuL3]3+·0.5{[Lu[(NO3)5(H2O)]2−·2[Lu(NO3)3(H2O)3]·4(NO3)−}6−·2(CH3NO2)·0.75(H2O) (1) (where L is napy-CMe2–P(O)Ph2, and napy is 1,8-naphthyridin-2-yl) was determined by single-crystal X-ray diffraction and discussed with respect to structures of other previously studied crystal Ln complexes of this ligand (2–4). Complex cation [LnL3]3+ (Ln = Nd, Eu, Lu) is the main structural component of compounds 1–4. Intramolecular interligand π-stacking interaction is observed in all [LnL3]3+ cations between three adjacent molecules of ONN coordinated ligands. π-Stacking interaction energy was estimated from Bader’s AIM theory calculations performed on DFT level. The data of ESI-MS agree well with assumption on π-stacking interaction. The lanthanide complexes [LnL3]3+ (Ln = Nd, Eu, Lu) are the first example of mononuclear complexes with triple intramolecular π-stacking in ligand system of complex.

The lanthanide complexes [LnL3]3+ (Ln = Lu, Eu, Nd, L = 1,8-naphthyridin-2-yl-CMe2P(O)Ph2) are first example of mononuclear complexes with triple intramolecular π-stacking in ligand system of complex.Figure optionsDownload as PowerPoint slide