Dehydro coupling of aromatic nuclei by catalyst-oxidant systems: poly(p-phenylene)

Chemisorption of Benzene on Cu-Montmorillonite as Characterized by FTIR and 13C MAS NMR

“…The Type II complex is characterized by a band at 800 cm -~ ( Figure 1E), which has been attributed to the formation ofpolyp-phenylene (Stoessel et al, 1977). In the polymer literature, the IR absorption band at 803-805 cm -] is indicative of parasubstitution in poly-p-phenylene (Kovacic and Jones, 1987).…”

“…The presence of water molecules during the equilibration of benzene with the partially hydrated clay film may have contributed to the formation of bands attributable to oxygen and/or hydrogen containing surface species (Kovacic and Jones, 1987;see Figures 6A and 6B). The cation radical can also be subject to fragmentation resulting in the formation of aliphatic reaction products.…”

“…The likely electronic structure of the doped poly-p-phenylene is thought to consist of a sequence of paraquinoid benzene rings intercalated between benzenoid rings, thereby forming a bipolaron ( Figure 7B). The formation of the chemisorbed complex in the interlamellar region of Cu +2 saturated smectires (Doner and Mortland, 1969), recently attributed to doped poly-p-phenylene (Soma et aL, 1984), has since been recognized as one of the more novel ways of synthesizing poly-p-phenylene by Kovacic and Jones (1987). The weight gained/lost of the self-supporting clay film, measured along with the formation of new vibrational bands in the combined gravimetric-vibrational experiment, is more difficult to interpret because of occurrence of several concomitant processes (e.g., dehydration, chemisorption, etc.…”

Heliphenes and Related Structures

“…Wynberg and coworkers [85] had described dehydrohelicenes obtained from [5]and [6]helicenes by AlCl 3 -catalyzed intramolecular dehydrogenation (Scholl reaction [86]). In the benzenoid series, simi- Fig.…”

Synthesis, processing and material properties of conjugated polymers

“…Thus, it has been claimed that polyphenylenes with ortho linkages can be obtained from the oxidative polymerization of monosubstituted benzenes (e.g. toluene, chlorobenzene) under conditions analogous to those employed for the preparation of poly(p-phenylene) 86 sulfuric acid in the presence of AICI3 are claimed to result in the efficient formation of homogenous poly-(p-phenylene) which is almost completely amorphous 94.…”