The Heck reaction allows the synthesis of monomers in a one-step reaction. Catalyzed by Pd, bromoarenes are reacted with ethylene to form substituted styrenes and symmetrical stilbenes. Unsymmetrical stilbenes are obtained from substituted bromoarenes and styrenes. Substituted hydroquinones and terephthalic acids are also available in high yields. Poly(l,4-phenylenevinylene) is obtained starting from 4-bromostyrene. Experimental partA typical procedure for the synthesis of a styrene and a stilbene derivative is given. Experimental conditions for other monomers are shown in Tab. 1.Reagents: DMF: distilled over 4,4 '-methylenedi(pheny1 isocyanate) and dibutyltin dilaurate as catalyst. Pd(OAc)2: used as received (Degussa). Tri-o-tolylphosphine: synthesized according to lit. '). Triethylamine, tributylamine: distilled over KOH. Styrene: used as received (stabilized with catechol). 4-Vinylbenzamide (6):A flame-dried pressure vessel of 100 ml volume was loaded under argon with 7 g (35 mmol) of p-bromobenzamide, 0,21 g (0,7 mmol) of tri-o-tolylphosphine, 0,078 g (0,35 mmol) of palladium acetate, 5,46 ml (40 mmol) of triethylamine, and a teflon@coated stir bar. 60 ml of DMF were added and a pressure of 72 bar ethylene (room temperature) applied. The autoclave was heated to 130°C for 24 h. The reaction mixture was precipitated with 400 ml of water and the solid dissolved in acetone. The filtered solution was concentrated and the residue was purified by sublimation. Yield: 3,7 g (72%), m.p. 176-177 "C, determined by DSC (lit.5): 170°C).

Poly(thio-l,4-phenylene)~ (PPS) 5ad with reactive end groups like carboxyl, nitro, cyan0 and aldehyde groups were synthesized under high as well as atmospheric pressure. Carboxyl terminated telechelics 5a were used as starting materials for the synthesis of poly(thio-l&phenylene)block-polyamides. Semicrystalline and amorphous polyamides like Nylon 6 and Tkogamide@ served as coblocks. The formation of block copolymers was approved by the solubility behavior, the NMR and IR spectra as well as high temperature GPC. The thermal stability increases with the fraction of PPS. By DSC, phase separation of the block copolymers was observed at certain compositions and molecular weights. Experimental partReagents and solvents. N-Methyl-e-caprolactam (NMC) and 1 -methyl-2-pyrrolidone (NMP) were distilled over 1,hapthylene diisocyanate and dibutyltin dilaurate as catalyst and than distilled over CaH2. 1,4Dichlorobenzene was distilled and recrystallized from methanol (m.p.

Trifluoromethyl-, pentafluoroethyl-and other perfluoroalkylbenzenes (2 ad, 4 and 3) were prepared by the reaction of the corresponding aromatic halides with perfluorocarboxylic acids in the presence of copper(1) iodide. These products were modified by oxidation or (and) substitution reactions and subsequently polymerized to give perfluoroalkyl-substituted polyamides, polyesters and poly(thio-l,4-phenylene)s showing good solubility.

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