Synthesis, solid-slate structure, magnetic properties and Mossbauer spectral studies of {Fe[HC(3,5-Me2pz)3](H2O)3} (BF4)2

The reaction of Fe(BF4)(2). 6H(2)O and one equivalent of HC(3,5-Me(2)pz)(3) in acetonitrile leads to the formation of {Fe[HC(3,5-Me(2)pz)(3)](H2O)(3)}(BF4)(2). The solution phase H-1 NMR spectrum is broad with chemical shifts ranging from 54 to -42 ppm, a range that is indicative of a paramagnetic high-spin complex. Magnetic moment measurements show that the complex is paramagnetic in the solid-state with mu (eff)=4.89 mu (B). The solid-state structure shows the N3FeO3 central core is a distorted octahedron with N-Fe-N angles averaging 84.4 degrees and O-Fe-O angles averaging 90.0 degrees. The average Fe-N distance is 2.18 Angstrom and the average Fe-O bond distance is 2.12 Angstrom. Mossbauer spectra, obtained at 78 and 295 K, clearly reveal that this complex is high-spin at these temperatures with hyperfine parameters typical of a pseudooctahedral iron(II) complex. (C) 2001 Elsevier Science B.V. All rights reserved.