Synthesis of α,ω-difunctionalized oligo- and poly(p-phenyleneethynylene)s

The synthesis and characterization of soluble rodlike oligo-and poly(1,4-phenyleneethynylene)s end-capped with various functional groups were achieved. The molecular weights were estimated by GPC and H-1 NMR spectroscopy. The possibility of quantitatively introducing different or identical functional groups at the chain ends was demonstrated by the synthesis of donor-and acceptor-substituited oligo(1,4-phenyleneethynylene)s and of poly(1,4-phenyleneethynylene)s functionalized with protected thiol moieties. The latter polymers can, after deprotection of the thiol functions, possibly serve as molecular wires and allow the bridging of a small gap between two gold nanoelectrodes.