Jean-Claude Bunzli - Synthesis and Photophysical Properties of Ln(III)-DOTA-Bipy Complexes and Ln(III)-DOTA-Bipy-Ru-II Coordination Conjugates

Version 1

      Publication Details (including relevant citation   information):

      Lopez,M.V., Eliseeva,S.V., Blanco,J.M., Rama,G., Bermejo,M.R.,   Vazquez,M.E., Bunzli,J.C.G. European Journal of Inorganic   Chemistry 2010 (28) 4532-4545

      Abstract: The synthesis and the systematic and   comparative photo-physical study of a series of visible (Eu-III,   Tb-III) and NIR-emitting (Nd-III, Yb-III) lanthanide complexes   (Ln(2)L) and ruthenium lanthanide coordination conjugates   (Ln(2)LRu) are reported. The Gd-III complex, the Gd-III-Ru-II   coordination conjugate, as well as the Ru-II complex of the   ligand H6L have also been synthesized and photophysically studied   as control systems. The ligand H6L, composed of a central   bipyridine binding unit and functionalized on each 5'-position   with a DOTA macrocycle, has been successfully synthesized from   cyclen, 5,5'-dimethyl-2,2'-bipyridine and 1,2-ethylendiamine in a   nine-step process. Detailed luminescence studies of all   complexes, including the determination of the quantum yield and   lifetime, were carried out on finely powdered microcrystalline   samples as well as in water, deuterated water and [D-6]DMSO at   ambient (295 K) and low temperature (77 K). The photophysical   data corroborate the existence of energy transfer in the Ln(2)L.   complexes and in the Nd2LRu coordination conjugate. However, no   (or at most, very little) energy transfer is takes place from the   Ru(bipy)(3) chromophore to the Ln(III) ion in the other Ln(2)LRu   heteropolymetallic complexes. Moreover, the photophysical studies   reveal that all the complexes and coordination conjugates adopt   different conformations and hydration states in solution and in   the solid state, which influences the efficiency of the energy   transfer between the bipy and/or Ru(bipy)(3) antennae and the   Ln(III) ions

      Address (URL): J INORG CHEM