Soluble poly(para‐phenylene)s, 3. Variation of the length and the density of the solubilizing side chains

Abstract The synthesis of a variety of alkyl‐chain‐substituted poly( para ‐phenylene) (PPP) derivatives, including those with systematically decreased density of side chains, is described, using for their preparation the Pd‐catalyzed polymerization method recently developed in Mainz (Mainz route to PPP's). The degrees of polymerization achieved range between 30 and 50, allowing the synthesis of structurally well‐defined and soluble PPP's with more than hundred 1,4‐phenylene rings attached to each other.