Reaction between yttrium nitrate and 2,2 ': 6 ',2 ''-terpyridine (terpy) in MeCN: Preparation, crystal structures and spectroscopic characterization of [Y(NO3)(3)(terpy)(H2O)] and [Y(NO3)(3)(terpy)(H2O)] center dot terpy center dot 3 MeCN

The reaction of Y(NO3)(3). 5H(2)O and 2,2':6',2"-terpyridine (terpy) in MeC N lends to [Y(NO3)(3) (terpy)(H2O)] (1) and [Y(NO3)(3)(terpy)(H2O)]. terpy . 3MeCN (2) in good yields depending on the isolation conditions. The struc tures of both complexes were determined by single-crystal X-ray crystallogr aphy. The Y-III atom in 1 is 9-coordinate and ligation is provided by one t erdentate terpy molecule, two chelating nitrates, one monodentate nitrate a nd one terminal H2O molecule; the coordination polyhedron about the metal m ay be viewed as a tricapped trigonal prism. The Y-III atom in 2 is 10-coord inate and its coordination sphere consists of three nitrogen atoms from the terdentate terpy, six oxygen atoms from the three chelating nitrates tone of them being "anisobidentate") and one oxygen atom from a terminal H2O mol ecule; the polyhedron about the metal may be viewed as a distorted sphenoco rona. The interstitial terpy is strongly hydrogen-bonded to the O atom of t he coordinated H2O molecule to form [Y(NO3)(3) (terpy)(H2O)]. . . terpy pai rs. The new complexes were characterized by IR and H-1 NMR spectroscopies. The Y-III/NO3-/terpy chemistry is compared to the already well-developed Ln (III)/NO3-/terpy chemistry (Ln = lanthanide).