IRON(II) POLYAMINE CHEMISTRY - VARIATION OF SPIN-STATE AND COORDINATION-NUMBER IN SOLID-STATE AND SOLUTION WITH IRON(II) TRIS(2-PYRIDYLMETHYL)AMINE COMPLEXES
A. Diebold et Ks. Hagen, IRON(II) POLYAMINE CHEMISTRY - VARIATION OF SPIN-STATE AND COORDINATION-NUMBER IN SOLID-STATE AND SOLUTION WITH IRON(II) TRIS(2-PYRIDYLMETHYL)AMINE COMPLEXES, Inorganic chemistry, 37(2), 1998, pp. 215-223
The synthetic system of Fe(SO3CF3)(2) and one or two TPA ligands (TPA
= tris(2-pyridylmethyl)amine) affords a series of complexes that demon
strate the complexities of the solid-state and solution coordination c
hemistry of labile iron(II) even with a multidentate ligand. The low-s
pin [Fe(TPA)(CH3CN)(2)](SO3CF3)(2) (1-OTf) complex forms in acetonitri
le, but the high-spin complex Fe(TPA)(SO3CF)(2) (2) forms in chlorofor
m. The methanol-bound complex [Fe(TPA)(CH3OH)(2)](BPh4)(2) (3) forms i
n the presence of the noncoordinating anion, BPh4-, and six-coordinate
[Fe(TPA)(2)](SO3CF3)(2) (4-OTf) and eight-coordinate [Fe(TPA)(2)](BPh
4)(2) (4-BPh4) form in the presence of excess ligand. Their behavior i
n solution is explored by studying their magnetic properties and NMR s
pectra, which indicate the presence of spin and coordination equilibri
a. The crystal structures of these complexes are reported. Crystallogr
aphic parameters are as follows. 1-OTf . CH3CN: C26H27F6FeN7O6S2, mono
clinic, P2(1)/n, a = 12.418(2) Angstrom, b = 16.192(4) Angstrom, c = 1
5.855(2) Angstrom, beta = 92.09(2)degrees, Z = 4. 2: C20H18F6FeN4O6S2,
monoclinic, P2(1)/c, a = 17.636(2) Angstrom, b = 9.659(1) Angstrom, c
= 16.004(2) Angstrom, beta = 113.29 (1)degrees, Z = 4. 3 . CH3OH: C69
H70B2FeN4O3, monoclinic, P2(1)/n, a = 17.525(1) Angstrom, b = 19.150(2
) Angstrom, c = 17.703(1) Angstrom, beta = 100.36(1)degrees, Z = 4. 4-
OTf: C38H36F6FeN8O6S2, monoclinic, Pc, a = 10.236(1) Angstrom, b = 10.
129(1) Angstrom, c = 19.251(1) Angstrom, beta = 92.27(1)degrees, Z = 2
. 4-BPh4: C84H76B2FeN8, monoclinic, P2(1)/n, a = 12.489(1) Angstrom, b
= 14.189(1) Angstrom, c = 19.843(1) Angstrom, beta = 102.84(1)degrees
, Z = 2.