Copper(II) complexes containing tetrathiafulvalene substituted by a bipyridine ligand: Synthesis, X-ray diffraction and EPR characterizations

We report a preliminary study of two novel complexes combining a paramagnetic transition metal (Cu(II)) and a cyclophane-type TTF-bipyridine ligand TTF-bipy = (cis)2,7-bis(pentylsulfanyl)-3,6-[2,2′-bipyridine-bis(4,4′-methanediyl)bis-sulfanyl]tetrathiafulvalene. The syntheses of the complexes Cu(hfac)2(TTF-bipy) (hfac = hexafluoroacetylacetonate) and Cu(NO3)2(TTF-bipy)·H2O are reported. The results of single-crystal EPR measurements are discussed on the basis of structural features deduced from preliminary X-ray diffraction data and indicate that these neutral molecular complexes behave as isolated paramagnetic units.