Synthesis and physical studies of lanthanide(III) complexes of N,N-bis(2-hydroxyethyl)glycinate (bicinate, bicH2 −): molecular and crystal structure of [Gd(O2CMe)(bicH2)(phen)(H2O)](ClO4).phen.3H2O (phen=1,10-phenanthroline)

Synthetic and isolation procedures are described that allow access to the new complexes [Ln(O2CMe)(bicH2)(phen)(H2O)](ClO4)·phen·3H2O, where Ln=Gd(1), Er(2), Pr(3) and Nd(4), bicH2 −=the monoanion of N,N-bis(2-hydroxyethyl)glycine (bicine) and phen=1,10-phenanthroline. The structure of 1 has been determined by single-crystal X-ray crystallography. The GdIII ion is in a 9-coordinate, tricapped trigonal prismatic ligand environment. The acetate and phen ligands are bidentate chelating, while the bicinate(−1) ion functions as a tetradentate chelate with the ligated atoms being the nitrogen, the two hydroxyl oxygens and one of the carboxylate oxygens. The crystal structure is stabilized by H bonds and aromatic stacking interactions. Complexes 2, 3 and 4 seem to be isostructural with 1. The complexes were characterized by elemental analyses, thermal techniques, room temperature magnetic moments and spectroscopic (IR, far-IR, solid state f–f) methods. All data are discussed in terms of the nature of bonding and known or assigned structures.