Solvation effects on the valence tautomeric transition of a cobalt complex in the solid state

Abstract

A detailed investigation of a valence tautomeric (VT) transition for the new complex [CoIII(3,5-DBCat)(3,5-DBSQ)(py)2]/[Co II(3,5-DBSQ)2(py)2] (1) is reported, where 3,5-DBCatH2 is 3,5-di-tert-butyl-catechol, 3,5-DBSQH is 3,5-di-tert-butyl-semiquinone and py is pyridine. Complex 1 exists as a mixture of the two valence tautomers, with the relative proportion of each depending on the external conditions. Three differently solvated forms of the complex have been synthesized and variable temperature structural and magnetic investigations of one of these, 1·0.5py, reveals that this compound undergoes a thermally-induced VT transition from the [CoIII(3,5-DBCat)(3,5-DBSQ) (py)2] tautomer at temper..