Luminescence of New 2,6- and 1,5-Naphthalene-Based PPV-TypeTrimers and Polymers

A series of new soluble 2,6- and 1,5-conjugated naphthalene-based PPV-analogous trimers (1a,b−6a,b) and polymers (24, 25, 26) have been synthesized by means of Knoevenagel and Wittig reactions, combining appropriate 1,5- and 2,6-functionalized naphthylene or phenylene building blocks. The influence of cyano substituents at the vinylic double bonds of the aromatic chromophores, and of the way in which they are linked, on the absorption and photoluminescence spectra has been investigated. The electroluminescent behaviour of the new compounds has been studied in ITO/copper phthalocyanine (PcCu)/emitter (trimer or polymer)/Al devices, demonstrating the aptitude of trimeric and polymeric 1,5-naphthylenevinylenes for use in organic light-emitting diodes for the first time.