Heterotrinuclear [Fe2IIINiII]-µ3-oxo-cluster Based on Salicylic Acid. Synthesis, Structure and Physico-chemical Properties

Synthesis and Characterisation of New {Fe2CrO} Heterotrinuclear Iron-chromium Clusters

Two new μ3-oxo trinuclear heterometallic Fe2IIICrIII complexes with furan-2-carboxylic and salicylic acids with the composition: [Fe2CrO(C4H3OCOO)6(CH3OH)3]NO3·0.5CH3OH and [Fe2CrO(C6H4(OH)COO)7(CH3OH)2]·2DMA were synthesized starting from iron(III) and chromium(III) salts mixture. The complexes structures were confirmed by elemental analysis, IR, Mössbauer spectroscopies, and X-ray analysis. The atomic absorption spectroscopy confirmed that the iron: chromium ratio is 2:1. The thermal properties of both heteronuclear complexes have been investigated in oxidizing and inert atmospheres revealing the stability of the trinuclear core up to 170 and 220°C, respectively.

Synthesis and Structural Characterization of the Tetranuclear Iron(Iii) Cluster with Salicylic Acid

A new tetra-homonuclear iron(III) cluster, [Fe4O2(Sal)4(H2O)6]·4DMA·0.75H2O, where Sal= salicylic acid and DMA= N,N-dimethylacetamide consolidated via two µ3-oxo- and four salicylate-bridges was synthesized and characterized by IR spectroscopic method as well as by single crystal X-ray diffraction analysis. The structure of the obtained tetranuclear compound consists of four FeIII atoms in a “butterfly” arrangement. The coordination sphere of each of the two central FeIII atoms is generated by two μ3-oxo-bridging atoms and four oxygen atoms provided by the tridentate-bridging Sal2- ligands, while the coordination polyhedron of another two iron atoms involve six oxygen atoms from three water molecules, two salicylic and one μ3-oxigen atom. The Fe-O distances within Fe-O-Fe bridge are of 2.102(3) Å (for wing-body) and 2.038(3) Å (for body-body).