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The five-coordinate iron-dithiolate complex (N,N′-4,7-bis-(2′-methyl-2′-mercatopropyl)-1-thia-4,7-diazacyclononane)iron(III), [LFe]⁺, has been isolated as the triflate salt from reaction of the previously reported LFeCl with thallium triflate. Spectroscopic characterization confirms an S = 1/2 ground state in non-coordinating solvents with room temperature μ_eff = 1.78 μ_Β and electron paramagnetic resonance (EPR) derived g-values of g₁ = 2.04, g₂ = 2.02 and g₃ = 2.01. [LFe]⁺ binds a variety of coordinating solvents resulting in six-coordinate complexes [LFe-solvent]⁺. In acetonitrile the low-spin [LFe-NCMe]⁺ (g₁ = 2.27, g₂ = 2.18, and g₃ = 1.98) is in equilibrium with [LFe]⁺ with a binding constant of K_eq = 4.7 at room temperature. Binding of H₂O, DMF, methanol, DMSO, and pyridine to [LFe]⁺ yields high-spin six-coordinate complexes with EPR spectra that display significant strain in the rhombic zero-field splitting …