ic5b02833_si_003.cif (20.77 kB)
Mononuclear, Dinuclear, and Trinuclear Iron Complexes Featuring a New Monoanionic SNS Thiolate Ligand
dataset
posted on 2016-01-19, 00:00 authored by Uttam
K. Das, Stephanie L. Daifuku, Serge I. Gorelsky, Ilia Korobkov, Michael L. Neidig, Jennifer J. Le
Roy, Muralee Murugesu, R. Tom BakerThe
new tridentate ligand, SMeNHS = 2-(2-methylthiophenyl)benzothiazolidine,
prepared in a single step from commercial precursors in excellent
yield, undergoes ring-opening on treatment with Fe(OTf)2 in the presence of base affording a trinuclear iron complex, [Fe3(μ2-SMeNS–)4](OTf)2 (1) which is fully characterized by structural and spectroscopic methods.
X-ray structural data reveal that 1 contains four SMeNS– ligands meridionally
bound to two pseudooctahedral iron centers each bridged by two thiolates
to a distorted tetrahedral central iron. The combined spectroscopic
(UV–vis, Mössbauer, NMR), magnetic (solution and solid
state), and computational (DFT) studies indicate that 1 includes a central, high-spin Fe(II) (S = 2) with
two low-spin (S = 0) peripheral Fe(II) centers. Complex 1 reacts with excess PMePh2, CNxylyl (2,6-dimethylphenyl
isocyanide), and P(OMe)3 in CH3CN to form diamagnetic,
thiolate-bridged, dinuclear Fe(II) complexes {[Fe(μ-SMeNS–)L2]2}(OTf)2 (2–4).
These complexes are characterized by elemental analysis; 1H NMR, IR, UV–vis, and Mössbauer spectroscopy; and
single crystal X-ray diffraction. Interestingly, addition of excess
P(OMe)3 to complex 1 in CH2Cl2 produces primarily the diamagnetic, mononuclear Fe(II) complex,
{Fe(SMeNS–)[P(OMe)3]3}(OTf) (5).
