Intramolecular electron transfer in the mixed-valence [Co(3,5-DTBCat)(3,5-DTBSQ)(bpy)] complex: Beyond valence tautomerism

The series of complexes [Co(Q)2(bpy)]n (n = −1, 0, +1) that can be derived by partial reduction or oxidation of complex 1, ls-Co(III) has been synthesized and studied. The results support the theoretical calculations which pointed to an intervalence transfer (IT) from the Cat2− to the SQ− ligand rather than a LMCT transition as the origin for the low-energy band transition centered at 2500 nm observed for 1, ls-Co(III).

Graphical abstractThe generation of the different species that can be derived by partial oxidation or reduction of complex [Co(3,5-DTBCat)(3,5-DTBSQ)(bpy)] has been used to demonstrate the existence of intramolecular electron transfer processes between ligands in view of the simultaneous existence of a catecholate and semiquinone, the donor and acceptor units, respectively.Figure optionsDownload full-size imageDownload as PowerPoint slide