Synthesis, structure and near-infrared luminescence of neutral 3d-4f bi-metallic monoporphyrinate complexes

The interaction of cationic lanthanide complexes [Ln(porp)(H2O)(3)](+) (Ln = Er or Yb; porp = porphyrinate) with sodium (cyclopentadienyl) tris( dieth ylphosphito) cobaltate (NaLOEt) gives the neutral 3d-4f bi-metallic porphyr inate complexes, [(L-OEt)Ln(porp)]. X-Ray structural analyses reveal that t hese complexes are seven-coordinate with the three oxygen atoms of the O-3- tripodal ligand, L-OEt, coordinated to the lanthanide metal behaving as a 6 -electron donor. Photophysical measurements show that the porphyrinate liga nd behaves as a sensitizer by absorbing visible light to excite the Ln(III) metal ions, producing near-infrared emission.