Perylene-perchlorate

Oberrauch et al.63 have studied the electrochemical production and reactivity of the radical cation perylene, in the presence of various monomers. Perylene perchlorate C20H12+ CIO4- (pp) was prepared via an electrocrystallization technique in acetonitrile or nitroethane. Styrene, a-methylstyrene, IBVE, NBVE, NVCZ, isobutene, piperylene, THF, were tested. The electronic spectra of the obtained polymers show that the polymerization takes place via electron transfer ... 

Table 2.3. Electrical conductivity of perylene-perchlorate salts...

Rosseinsky, D. R. et al., J. Chem. Soc., Perkin Trans. 2, 1985, 135-138 The title compound, prepared by electrolysis of perylene and tetrabutylammo-nium perchlorate in nitrobenzene, exploded on contact with nickel. Co-produced compounds should also be handled with caution and in small amounts, especially in contact with metals. 

Synthesis of Radical Cation Perchlorates and Subsequent Coupling with NucleophilesT Syntheses of the radical cation perchlorates of BP and 6-methylBP (12) were accomplished by the method reported earlier for the preparation of the perylene radical cation (13,14). More recently we have also synthesized the radical cation perchlorate of 6-fluoroBP (15). Oxidation of the PAH with iodine in benzene in the presence of AgClO. instantaneously produces a black precipitate containing the radical cation perchlorate adsorbed on Agl with... 

Several examples of the use of microelectrodes in highly resistive media exist. The first reported measurements were an examination of the reduction of aromatic hydrocarbons such as perylene in benzene containing tetrahexylammonium perchlorate [57]. Although this electrolyte is presumably in a quite associated state in benzene (or toluene [58]), it does impart sufficient conductivity for electrochemistry to be observed. In subsequent work, this result was confirmed and extended to other low-dielectric-constant solvents [59]. Even voltammetry in hexane has been shown to be possible with a microelectrode [60]. In this sol-... 

Figure 14. Electropherogram of neutral organic compounds in 50/50 acetonitrile/water with 0.025 M tetrahexylammonium perchlorate. A = benzo-(GHI) perylene B perylene C pyrene ...

Perchloric acid oxidizes perylene (Matsunaga, 1961), thianthrene and phenoxathiin (Murata and Shine, 1969) to the cation radicals, but whether or not the acid serves as the oxidizing agent or catalyses oxidation by atmospheric oxygen has not been studied. 

Use of iodine-silver perchlorate may accomplish cation-radical formation before the oxidizing pair can themselves react. In modern usage, silver ion (as the perchlorate usually) is added to a solution of the substrate and iodine, and the complexity of the iodine-silver perchlorate system is avoided, provided that the substrate undergoes reasonably fast oxidation. Such is the case with perylene (Sato et al., 1969 Ristagno and Shine, 1971) and pheno-thiazine, but not the case with diphenylanthracene and thianthrene (Shine et al., 1972). 

Anodic oxidation of perylene, pyrene, and azulene (Ristagno and Shine, 1971a, b Reddoch et al., 1971) has given the aromatic perchlorate complexed with the aromatic in what appears to be an ArH. ArH +C104 salt. The salt deposits on the anode. 

We have already referred to oxidations by iodine-silver perchlorate (p. 168). This is an easy way of making the perchlorates of some cation radicals such as of perylene (Sato et al., 1969 Ristagno and Shine, 1971b). In appropriate circumstances, silver ion itself should be able to oxidize some compounds to their cation radicals, and this has been achieved with some 2-phenyl-3-arylaminoindoles and silver perchlorate in acetone or acetonitrile a silver mirror is formed (Bruni et al., 1971). 

Formation of dicationic dimers (90) has been longer known than formation of the monocationic type (89), no doubt because of the availability of and interest in the very stable Wurster Salts. Hausser and Murrell (1957) proposed that the long wave-length absorption band (near 800 nm) of Wurster s Blue perchlorate in ethanol at —90° was caused by two associated, cation radicals lying in parallel planes. Since that time a considerable number of workers have explored the dimerization of Wurster and analogous cation radicals, (e.g. Kawamori et al., 1966 Kimura et al., 1968). Not only does Wurster s Blue cation radical (i.e. TMPD +) associate with itself, but it also forms a spin paired dimer with p-phenylenediamine cation radical (PD +). In fact, Takimoto et al. (1968) conclude from absorption spectroscopy that solutions of TMPD + and PD + in ethanol-ether at —195° contain (PD"+)2 and (PD"+-TMPD +)2 but very little of (TMPD +)2. Dimerization of unlike cation radicals is known in other systems too. Perylene" and naphthacene4-each forms an (M"+)2 dimer in sulfuric acid at reduced temperatures (Kimura et al., 1971). Mixtures of the two cation radicals in sulfuric acid leads to a mixed dimer too, (Perylene "+, naphthacene +), the heat of formation of which (—7-7 kcal mole-1) incidentally, lies between that of the perylene"+ (—8-8) and naphthaccne + (— 5 6) dimers (Yamazakiand Kimura, 1972). 

Because the cyanide ion is so easily oxidized its apparent ability to react with aromatic cation radicals instead of being oxidized by them reflects the competition so often encountered in cation radical chemistry between nucleophilicity and oxidizability of a nucleophile. The subject has not been treated analytically yet. In the present context, the tri-p-anisylaminium ion is reduced by cyanide ion (Papouchado et al., 1969) in a very fast overall second-order reaction (Blount et al., 1970). The cation radicals of thianthrene, pheno-thiazine, and phenoxathiin are also reduced by cyanide ion (Shine et al., 1974). In none of these cases, incidentally, is the fate known of the cyano radical presumed to be formed. Perylene cation radical perchlorate, on the other hand, reacts with cyanide ion in acetonitrile solution to give low (13%) yields of both 1- and 3-cyano-perylene (Shine and Ristagno, 1972). 

Fluoride ion reactions are somewhat puzzling. Oxidation of fluoride ion by a cation radical is out of the question and nucleophilic attack would appear to be certain. However, this reaction has failed completely with several cation radical perchlorates, such as those from perylene (Ristagno and Shine, 1971b), and phenothiazine (Shine et al., 1972). It appears that fluoride ion is too weak a nucleophile to participate in such substitution reactions. On the other hand, several cases of anodic fluorination are known oxidation of some aromatics, in solutions containing fluoride ion and at potentials lower than the oxidation potential of fluoride ion, has led to fluorination. This has occurred with naphthalene, which gave... 

These are undoubtedly the most widely studied compounds of perylene with simple anions, mainly AsFg and PFg and their solid solutions, and for some stoichiometries the most conductive at room temperature. Besides the several stoichiometries they present, as in the perchlorate salts [3,36], an additional problem comes from the incorporation of solvent in the crystal structure. In the following we will divide into sections the discussion of the different aspects of the chemistry and physics of these compounds and their solid solutions. 

In order to avoid these limitations, there is a need for alternative electrolytes which work in both n-type and p-type systems. One such class of species is the cobalt polypyridyl complexes such as Co tris(4,4"-di-ferf-butyl-2,2"-dipyridyl) perchlorate.Gibson et al. employed this redox couple in a NiO-based p-type device in conjunction with two perylene-based dyes, PI and PINDI (Figure 3.74). ... 

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