Substituent Effect on Carbodithioate Ligand Field Strength in Iron(III) Carbodithioates: Synthesis and Characterization

Abstract

New iron(III) carbodithioate complexes of the general formulae Fe(Lcdt)₃ [(where L is the anion of an heterocyclic amine and Lcdt are the following anions: 4-methylpiperazine-l-carbodithioate (4-MPipzcdt), 4-phenylpiperazine-l-carbodithioate (4-PPipzcdt), piperidinecarbodithioate (Pipdcdt), 2-methylpiperidine-carbodithioate (2-MPipdcdt), 4-methylpiperidine carbodithioate (4-MPipdcdt), morpholinecarbodithioate (Morphcdt), 2,6-dimethylmorpholinecarbodithioate (2,6-M₂Morphcdt), 2,5-dimethylpyrrolecarbodithioate (2,5-M₂Pyrrcdt)] and Fe₂[2-MPipz(cdt)₂]₃ [(2-MPipz(cdt)₂ = 2-methylpiperazine-l, 4-dicarbodithioate dianion)] have been synthesized. These compounds have been characterized by elemental analyses, infrared spectral and magnetic susceptibility measurements and in some cases by electron paramagnetic resonance studies. The room temperature magnetic moments of the complexes are indicative of a trigonally distorted octahedral geometry around iron(III) observing a ⁶A₁ ↔ ²T₂ spin croosover phenomenon. The EPR studies give the g_av values 4.4960-4.9962.