Perylene producers

Naphthalene, with an ionization potential higher than that of anthracene or perylene, produces a much lower radical concentration in the zeolite (Table I), and appears to have no observable enhancing effect on the formation of anion radicals. Probably only certain sites of high energy are involved in this oxidation, and these sites may not be of the type in which interaction with an adjacent reducing center is possible. 

The gas-phase 4- -2-cycloaddition of benzyne with perylene produced naphtho[l,2,3,4- fti]perylene under solvent-free conditions. The microwave-catalysed reaction of A-(2,4-dicyano-l,5-dimethyl-3-phenylcyclopenta-2,4-dienyl) 2,2,2-trifluoroacetamide with alkynes formed bicyclic and polycyclic compounds. The Diels-Alder reaction of maldoxin (67) with an isopropenylallene (68) yielded a cycloadduct (69) closely related to chloropestolide A and a second adduct, which... 

Decomposition of diphenoylperoxide [6109-04-2] (40) in the presence of a fluorescer such as perylene in methylene chloride at 24°C produces chemiluminescence matching the fluorescence spectmm of the fluorescer with perylene was reported to be 10 5% (135). The reaction follows pseudo-first-order kinetics with the observed rate constant increasing with fluorescer concentration according to = k [flr]. Thus the fluorescer acts as a catalyst for peroxide decomposition, with catalytic decomposition competing with spontaneous thermal decomposition. An electron-transfer mechanism has been proposed (135). 

Emission spectra at these points are shown in Figure 8.2d. The band shapes were independent of the excitation intensity from 0.1 to 2.0 nJ pulse . The spectrum of the anthracene crystal with vibronic structures is ascribed to the fluorescence originating from the free exdton in the crystalline phase [1, 2], while the broad emission spectra of the pyrene microcrystal centered at 470 nm and that of the perylene microcrystal centered at 605 nm are, respectively, ascribed to the self-trapped exciton in the crystalline phase of pyrene and that of the a-type perylene crystal. These spectra clearly show that the femtosecond NIR pulse can produce excited singlet states in these microcrystals. 

The electron transfer between an electrochemically produced perylene dianion and a C02 molecule was also suggested by cyclic voltammetry in a DMF solution.161 Later, perylene was used162 in the photochemical fixation of C02, as a nonmetal electron carrier to C02. 

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... 

A very efficient energy transfer (producing emission at 613 nm) was observed in PL spectra of the perylene end-capped polymer 361 in solid films. This material had the highest QE (>60%) among the fluorene- perylene polymers, although the performance of its PLED has not yet been reported [434],... 

Unsymmetrically substituted perylene pigments are a comparatively recent novelty. Selective protonation of the tetra sodium salt of perylene tetracarboxylic acid affords the monosodium salt of perylene tetracarboxylic monoanhydride in high yield. Stepwise reaction with amines produces unsymmetrically substituted perylene pigments [2],... 

The perylene pigment in which X= )N-CH2-CH2-0-CH2-CH3, for instance, affords a red shade, while X= )N-CH2-CH2-CH2-OCH3 produces a black shade. The difference in shade is attributed to a structurally controlled special arrangement of the pigment molecules within the crystal lattice. 

Low-temperature protonations of benzo[<3]coronene 90 and benzo[ /z/]perylene 91 were studied in FSO3H/SO2CIF and CF3SO3H/SO2CIF superacids (Fig. 31). For 90, rapid competing oxidation to the RC prevented the observation of 90H by NMR spectroscopy the RC was probed by ESR spectroscopy. For 91, competing oxidation was less problematic and a persistent arenium ion 91H could be seen by NMR which was line-broadened due to the presence of the RC. Protonation of a mixture of 90 and 4,5-dihydropyrene 1 produced the C-3 protonated IH and 90H. Addition of 1 to the superacid solution containing 91H and 91 led to the detection of the C-3 protonated IH and the disappearance of 91H (by NMR). 

A nanocrystalline Sn02 solar cell sensitized by a perylene derivative produced 0.9% efficiency under AM 1.5 (7 = 3.26 mA/cm2 and = 0.45 V) [132]. A nanocrystalline Ti02 solar cell (1 cm2) sensitized by eosin Y, oneof the... 

Since overlap of the spectra of the TNB anion radical and the anthracene cation radical is virtually confined to the central feature of the anion spectrum, observation of the intensity of one of the outer features permits separate assessment of the anion-radical concentration (Figure 2c). As in a previous investigation (2) a quantitative study of the enhancement of the ion-radical spectrum in the presence of coadsorbate was therefore possible by using a calibration curve in which the intensity of the outer line of the TNB spectrum was plotted against the doubly integrated area of the whole of the TNB spectrum in a separate series of experiments. Figure 3 shows the effect of added anthracene and perylene on the surface concentration of TNB anion radicals. A tenfold increase in the TNB radical concentration was observed in the presence of either hydrocarbon. Addition of naphthalene, on the other hand, produced no enhancement of the TNB anion-radical concentration. 

There are several natural non-combustion sources of PAHs. A study in 1980 by Wakeham [43] concluded that phenanthrene could be created by the dehydrogenation of steroids, retene could be produced by the diagenesis of abietic acid, and alkyl chrysenes could form from the degradation of the pentacyclic triterpenes alpha- and beta-amyrin, which are components of higher plant waxes. In this section we will look at the natural non-combustion sources of retene and perylene and how these sources might impact the Great Lakes. 

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