Synthesis and Electronic Spectra of Substitutedp-Distyrylbenzenes for the Use in Light-Emitting Diodes

The influence of substitution on the absorption and Luminescence spectra of oligo(phenylenevinylene)s has been studied using distyrylbenzene (DSB) as a model compound. The degree, character, and pattern of substitution was varied systematically, altering the electronic properties of the DSB, the wavelength of the emitted light could be tuned over a range of 100 nm. The syntheses of 6b—h were performed by twofold Wittig Horner-olefinations of bisphoshonates 1a, b with substituted benzaldehydes 2a—i, 6ivia Heck-reaction of the dibromosulfonylbenzene 3, 6k by Siegrist-reaction of 4 with N-phenylbenzaldimine and the Knoevenagel-reaction of benzyl cyanide with 5 led to 6l.