Blue emitting fluorophores of phenyleneethynylenes substituted by diphenylethenyl terminal groups for organic light-emitting diodes

Phenyteneethynylene motifs substituted by diphenylethenyl groups at both ends were prepared successfully by use of double elimination protocol of P-substituted sulfones for introducing phenyleneethynylene arrays followed by Wittig-Horner reaction for introducing diphenylethenyl moiety. The hybrid blue fluorophores exhibited strong emission even in the solid-state films (Phi(F) >= 0.60) while, in CHCl3 solution, incorporation of substituents on the central phenylene unit significantly enhanced emission efficiency UP to Phi(F) = 0.57. The OLED devices with use of these blue fluorophores as an emitting material provided maximum external quantum efficiency of eta(ext) = 2.4%. (C) 2009 Elsevier B.V. All rights reserved.