Molecular structure and paramagnetic properties of bis-diisobutyl- dithiophosphinate complexes of neodymium(III), europium(III) and ytterbium(III) with 1,10-phenanthroline using NMR

摘要

The features of the molecular structure and paramagnetic properties of Ln-containing complexes with the dithiophosphinate R_2PS _2 ~- (R = i-Bu) and 1,10-phenanthroline ligands [Ln(1,10-Phen)((i-Bu)_2PS_2)_2(NO_3)] {where Ln = Nd~(3+) (I), Eu~(3+) (II), Yb~(3+) (III) and Lu~(3+) (IV)} in CDCl_3 have been studied by ~1H NMR techniques. These complexes are of interest due to the prospect of using some of them as fluorescent sensors for biology and medicine. The structure of complexes was studied in detail by two independent 1H NMR techniques: Analysis of lanthanide-induced shift (LIS) magnitudes and calculation of paramagnetic lanthanide-induced relaxation rate enhancements. The structure results obtained for these paramagnetic complexes by relaxation spectroscopy (RS) of NMR and LIS analysis in solution are mutually consistent with the results found for model complex of yttrium by X-ray analysis in the crystalline phase. Paramagnetic complexes (I, II and III) investigated in the paper represent a new type of thermometric NMR sensors and lanthanide paramagnetic probes for in situ temperature control in solution.