Practical synthesis of vinyl-substituted p-phenylenevinylene oligomers andtheir triethoxysilyl derivatives

Luminescent semiconducting organic compounds are widely used as active laye rs in electro-optical devices. Apart from conjugated polymers, monodisperse oligomers also represent attractive materials. The synthesis of stilbenoid oligomers with polymerizable end groups is presented. Oligo(phenylenevinyl ene)s with terminal vinyl groups 17-19 are prepared in good yields by Horne r-Emmons olefinations or by the fleck reaction of the iodo-substituted olig omers 15, 16 with cornpressed ethene. Triethoxysilyl groups can be linked v ia rigid 1,2-vinylene units to the chromophores 26-30, either in the direct reaction of 14, 24 with silanes 21, 22 or by cross-metathesis of 17-19 wit h the vinyl silanes 21, 22 using Grubbs catalyst.