New mono and bimetallic iron complexes derived from partially methylated s-indacene. Evidence of a trinuclear iron s-indacene complex

The preparation and characterization of new mono- and multinuclear iron complexes derived from s-indacene partially alkylated has been achieved by the development of rational synthetic routes. The synthesis of the new multimetallic complexes are based on the employment of 1,5-dihydro-2,4,6,8-tetramethyl-s-indacene (Ic′H2) as ligand to obtain two monometallic complexes, namely, [Cp∗–Fe-(η5-2,4,6,8-tetramethyl-5-hydro-s-indacenide)] (1), and [Fe-bis(η5-2,4,6,8-tetramethyl-5-hydro-s-indacenide)] (2) (Cp∗ = pentamethylcyclopentadiene), as well as, the new bimetallic [Cp∗Fe-(μ:η5:η5-2,4,6,8-tetramethyl-s-indaceneiide)-FeCp∗] (3) and trimetallic [Fe-bis{Cp∗Fe-(μ:η5:η5-2,4,6,8-tetramethyl-s-indaceneiide)}] (4) complexes. All complexes here reported were characterized by means of 1H, 13C NMR, mass spectrometry, elemental analysis, together with cyclic voltammetry. In addition, these complexes have been studied by DFT methods in order to gain further knowledge about its electronic structure. In addition, the possibility to generate organometallic polymers employing the complexes here reported, is proposed theoretically with the study of an oligomer titled as [Cp∗{Fe(Ic′)}4FeCp∗], 6t.

Graphical abstractThis work describes the synthesis and characterization of new multinuclear iron complexes derived from s-indacene. All complexes were characterized by means of NMR, mass spectrometry, elemental analysis, and cyclic voltammetry. In addition, these complexes have been studied by DFT methods in order to gain further knowledge about its electronic structure.Figure optionsDownload full-size imageDownload as PowerPoint slide