Synthesis, X-ray structure and characterization of a novel [fc(IMH) 2H] +[Co(hfac) 3] − salt with hydrogen bonded ferrocenyl bis(imino hydroxylamino) building blocks

Abstract

The reaction of ferrocenylene bis(α-nitronyl nitroxide) diradical ( 1; [fc(NIT) 2]) with Co(hfac) 2 produces the reduction of the radical character of 1 with the formation of the diamagnetic ferrocenyl bis(α-imino nitroxide) cation, [fc(IMH) 2H] +, which forms with the [Co(II)hfac 3] −, as the counterion, the complex salt 4. This salt crystallizes in the P 1 ̄ spatial group exhibiting an exotic supramolecular architecture in which the molecular ions are bonded through hydrogen bonds forming single chains with a zipper-like arrangement. Remarkable is the presence in complex salt 4 of two proton tautomeric forms in the [fc(IMH) 2H] + units.