Experimental And Theoretical Analysis Of The Electronic Behavior In Five-Coordinate Iron(iii) And Six-Coordinate Cobalt(iii) Complexes With Electroactive Phenol-Rich Ligands
Three 5 coordinate high-spin Iron(III) complexes containing pentadentate N2O5 ligands were synthesized and characterized, namely, (1) [FeIII(L1)] and (2) [FeIII(L2)]. Structural differences in ligand design,N,N,N\u27-tris(3,5-di-tert-butyl-2-hydroxybenzyl)benzene-1,2-diamine for (1) and N,N,N\u27-tris-(3,5-di-tert-butyl-2-hydroxybenzyl)-N\u27-methyl-benzene-1,2-diamine for (2), result in complexes that due to their forced geometry, asymmetry, and slightly different electronic structures are able to foster phenoxyl radicals although show a sensitive dependence to both the solvent and the electrolyte system in the cyclic voltammetry. In the presence of TBAClO4 (1) exhibits a two-electron oxidation, whereas in the presence of TBAPF6 (2), , shows three distinct phenolato/phenoxyl radical couples. Both (1) and (2) were redox-cycled 30 times without major decomposition at the surface of the electrode, indicating that the oxidized species are substitutionally inert. Three six coordinates low spin Co(III) complexes were synthesized and their electrochemical reactions were investigated in details