Synthesis, crystal structure, and thermal behavior of a diiron toluenethiolate complex with triphenylphosphine coligand

A bis(p-toluenethiolato) dinuclear-carbonyl complex with triphenylphosphine coligand, [μ-(SC6H4CH3-p)2Fe2(CO)5(PPh3)], has been synthesized from [μ-(SC6H4CH3-p))2Fe2(CO)6] via facile CO substitution by PPh3 in 33% yield. The structure of [μ-(SC6H4CH3-p)2Fe2(CO)5(PPh3)] has been determined by X-ray crystallography and spectroscopic measurements. In the solid state, the compound adopts a butterfly conformation with anti-orientation of the p-tolyl groups and apical position of triphenylphosphine. Thermogravimetric studies reveal that [μ-(SC6H4CH3-p)2Fe2(CO)5(PPh3)] undergoes sequential decomposition eliminating all of the CO ligands at ca 197 °C, followed by cleavage of the tolyl and PPh3 groups below ca 258 °C.