A synthetic strategy leading to monodisperse PPV oligomers by coupling reactions of vinyltrimethylsilanes

A novel strategy for the synthesis of well-defined oligo(phenylenevinylene) s was developed. The procedure is entirely based upon two coupling processe s, both involving vinyltrimethylsilanes. Bis-(styryl)benzenes 2a-g bearing two octyloxy groups in the central aromatic ring and various substituents o n the external aromatic rings were prepared in good yield by a regio- and s tereoselective coupling reaction of 1 with different arenediazonium tetrafl uoroborates. Oligomers with a more extended conjugated system, 4a-c, and wi th m-phenylene subunits 13a,b, were also readily obtained by conversion of the unsaturated trimethylsilyl derivatives 3a,c,d to the corresponding boro n derivatives and a subsequent coupling reaction with compounds 2a and 2c.