Polymerization of aromatic nuclei. XXVII. ESR studies on polymers and oligomers from reaction of benzenoid and naphthalene monomers with lewis acid catalyst–oxidant systems

Chlorobenzene and toluene were polymerized with aluminum chloride–cupric chloride to produce materials that consist mainly of poly(o‐phenylene) structures. These species exhibited radical cation concentrations comparable to that of poly(p‐phenylene). Polymerization of naphthalene and 1‐chloronaphthalene with aluminum chloride–cupric chloride or ferric chloride–water also resulted in products with high radical cation concentrations. Polynuclear structures may be responsible for the paramagnetic character; alternatively, p‐quinoidal moieties may be present in naphthalenes. The depth of color in the samples is directly related to the concentration of radical cations.