The conjugate base of malonaldehyde as antenna-ligand towards trivalent europium and terbium ions

Coordination compounds having formulae [M(MA)(3)] (n) and M(MA)((Me2)Tp)(2) (M = Y, Eu, Tb; MA = conjugate base of malonaldehyde; (Me2)Tp = tris(3,5-dimethyl-pyrazol-1-yl)borate) were synthesized and characterized. The photoluminescence features of the europium and terbium derivatives were investigated. By comparing the herein reported photoluminescence data with those relative to analogous nitro- and bromomalonaldehyde derivatives, it appears that the conjugate base of malonaldehyde is a more efficient antenna-ligand for the sensitization of Tb(III) luminescence. The experimental data were rationalized on the basis of DFT calculations. Tb(MA)((Me2)Tp)(2) was used as dopant for the preparation of luminescent plastic materials based on poly(methyl methacrylate).