Chemical and Optical Propertiesof New Highly Luminescent Alternating Oligo- m , p -phenylenevinylenes

Summary. In this paper we report on the synthesis and characterization of a variety of poly-phenylenevinylene ( PPV ) derivatives containing para - and meta -linkages in the backbones. By the m -linkages the conjugation lengths of the oligo- m,p -phenylenevinylenes were limited, thus blueshifting the UV/Vis absorption and also the photoluminescence (PL) spectra. Alkoxy substituted oligo- m,p -phenylenevinylenes exhibited absorption and emission spectra at higher wavelengths than oligomers without oxygen directly attached to the backbone. Replacing p -phenylene by 4,4′-biphenylene moieties also led to a hypsochromic shift in the optical spectra. We chose the Heck coupling reaction to synthesize substituted oligomers consisting of alternating p -phenylenevinylene and m -phenylenevinylene units. They were characterized by 1 H NMR, 13 C NMR, FT IR, UV/VIS, and GPC analysis.