Inorganic Chemistry, Vol.53, No.2, 1128-1134, 2014
Synthesis and Characterization of Nickel(II) Phosphonate Complexes Utilizing Pyridonates and Carboxylates as Co-ligands
The synthesis and structures of five new nickel complexes containing phosphonate ligands are reported. The compounds utilize pivalic acid (HPiv) and 6-chloro-2-pyridonate (Hchp) as co-ligands with the resulting complexes being of formulas [Ni-10(chp)(4)(Hchp)(4.5)((O3PBu)-Bu-t)(3)(Piv)(5)(HPiv)(2)(OH)(6)(H2O)(4.5)](HNEt3)center dot 0.5MeCN center dot 2.5H(2)O 1, [Ni-12(chp)(12)(Hchp)(2)(PhPO3)(2)(Piv)(5)(HPiv)(2)(OH)(2)(H2O)(6)](F)center dot 4.5MeCN center dot 2H(2)O 2, [Ni-10(chp)(6)(O3PCH2Ph)(2)(Piv)(8)(F)(2)(MeCN)(4)] 3, [Ni-10(chp)(6)(O3PMe)(2)(Piv)(8)(F)(2) (MeCN)(4)]center dot 5MeCN center dot 2H(2)O 4, and [Ni-10(chp)(6)(O(3)PCH(2)Nap)(2)(Piv)(8)(F)(2)(MeCN)(2)(H2O)(2)] 5. The metallic core of compounds 1 and 2 display tetra- and hexa-capped trigonal prismatic arrangements, while the metallic and phosphorus core of 3, 4, and 5 display three face-sharing octahedra. Variable temperature direct current (dc) magnetic susceptibility measurements reveal dominant antiferromagnetic exchange interactions within each cluster, with diamagnetic spin ground states found.