Fluorinated polycyclic aromatic

Significant through-space scalar couplings have been observed only in rare cases and in very close spatial proximity and usually 19F is involved in such couplings102-105, e.g., in the following fluorinated polycyclic aromatic systems ... 

A wide variety of fluorinated aromatic and polyaromatic systems are accessible via the BS synthesis, such as 11, 13, 16, and 18-21 presented earlier. Other examples are fluorinated mesitylenes,43 several polyfluorinated benzenes,44, 4-chloro-2-fluoronitro-benzene,4S bromofluorotoluenes,46 7-fluoroindanone, 8 fluorinated polycyclic aromatic hydrocarbons,17,47 4-tritylfluorobenzene,48 fluorinated diaryl thioethers, fluorophenols,50 fluoronorepinephrines, fluorinated estrogens,19,S2 and an unusual metacyclophane.53 A selection of these compounds is shown here. 

Effects of Methyl and Fluorine Substitution on the Metabolic Activation and Tumorigenicity of Polycyclic Aromatic Hydrocarbons... 

NFTh (21) has been effectively used for selective fluorination of polycyclic aromatics. Thus, naphthalene can be site-selectively fluorinated to 1-fluoronaphthalene, phenanthrene to 9-fluorophenanthrene, and pyrene to 1-fluoropyrene.94,97 NFTh reacts with acetanilide to give a mixture of 2- and 4-fluoroacetanilide (67 33).91... 

A new thermal preparation of fluorinated species is copyrolysis Copyrolysis of fluorinated compounds like perfluorobenzene, fluorinated aromatic anhydndes, and fluorinated heteroaromatics with tetrafluoroethylene or other fluorinated olefins is a useful method of preparing fluorinated olefins [88 89], functionalized fluoroaromatics [90 91 92, 93, 94, 95], fluorinated benzocycloalkanes [80,96, 97, 98, 99, 100], fluorinated heterocycles [80, 93, 101, 102, 103], and fluorinated polycyclic compounds [104] (equations 19 and 20)... 

Abstract Pressure-sensitive paint (PSP) is applied to the areodynamics measurement. PSP is optical sensor based on the luminescence of dye probe molecules quenching by oxygen gas. Many PSPs are composed of probe dye molecules, such as polycyclic aromatic hydrocarbons (pyrene, pyrene derivative etc.), transition metal complexes (ruthenium(II), osumium(II), iridium(III) etc.), and metalloporphyrins (platinum (II), palladium(II), etc.) immobilized in oxygen permeable polymer (silicone, polystyrene, fluorinated polymer, cellulose derivative, etc.) film. Dye probe molecules adsorbed layer based PSPs such as pyrene derivative and porphyrins directly adsorbed onto anodic oxidised aluminium plat substrate also developed. In this section the properties of various oxygen permeable polymer for matrix and various dye probes for PSP are described. 

Many PSPs are composed of probe dyes, such as polycyclic aromatic hydrocarbons (e.g., pyrene) and coordination compounds (e.g., platinum por-phryins and ruthenium(II) polypyridyl complexes) immobilized in various gas permeable polymer films such as silicon polymer, organic glassy polymers (e.g., poly(methylmethacrylate), polystyrene), fluorinated polymers, or cellulose derivatives such as ethyl cellulose [9,10]. As probe molecules interact with polymer matrices directly, the properties of PSPs strongly depend on the properties of polymer matrices. The oxygen permeability of polymer matrix is an especially important factor for highly sensitive PSP. 

Fig. 2.20. Composition (mean%) of 16 individual polycyclic aromatic hydrocarbons (PAHs) to total PAHs detected in various environmental media in (a) air (n = 24), (b) soil (n = 226), (c) freshwater (n = 46), and (d) marine sediment (n = 159), from the South Korea. Naphthalene NAP, Acenaphthylene ACY, Acenaphthene ACE, Fluorine FLU, Phenanthrene PHE, Anthracene ANT, Fluoranthene FLT, Pyrene PYR, Benz[a]ant-hracene BaA, Chrysene CHR, Benzo[6]fluoranthene BbF, Benzo[ ]fluoranthene BkF, Benzo[a]pyrene BaP, Indeno[l,2,3,c,d]pyrene I123cdP, Dibenz[a,/z]anthracene DahA, Ben-zo[g,/y ]perylene BghiP.

Cations, polycyclic aromatic nitrogen (review), 55, 261 Cesium fluoroxysulfate fluorination of... 

The fluorination of aromatic compounds with xenon difluoride has been extensively investigated.180- 188 The fluorination of benzene with xenon difluoride in the presence of hydrogen fluoride as a catalyst results in the formation of fluorobenzene in 68% yield.180 Monosub-stituted aromatic systems are reported to give high yields of monofluorinated compounds, the isomer distributions of which are similar to those observed in electrophilic substitution (Table 14).181 Alkylaromatics, benzocyclenes and polycyclic aromatics are all successfully fluorinated by xenon difluoride in the presence of hydrogen fluoride examples are the fluorination of 21,182 22,182 23,184 185 24,185 and 25.182... 

Treating a bituminous coal with potassium hydroxide in glycols at 250°C yields a largely soluble product that results from the reduction of polycyclic aromatics and the cleavage of aryl ether linkages. The reduction in aromaticity was demonstrated in two ways. First, the fraction of aromatic carbons ( J of the soluble product, which was determined by NMR, was compared with the of the whole coal determined by fluorination. Secondly, the aromatic acids produced in a selective oxidation of both the product and coal were compared, and evidence for ether cleavage was obtained from the oxidation results. The effects of rank and different protic solvents on the reaction were examined. 

The linear acenes illustrate the effect of extended conjugation. As the number of rings is extended in both the hydrocarbons and perfluorinated hycrocarbons, the Ea increases. However, for a nonlinear extension the Ea may or may not increase. For example, the Ea of phenanthrene is 0.30 0.02 eV, while that for anthracene is 0.68 0.02 eV. Likewise, the Ea of benzanthracene is less than that of tetracene. The curves for the linear acenes are an upper limit for the electron affinities of polycyclic aromatic hydrocarbons with the same number of six membered rings. The inclusion of five or seven membered rings will increase the electron affinity above those with solely six rings. The simplest example is the Ea of azulene, 0.8 eV, versus that of naphthalene, 0.16 eV. Interestingly, the calculated electron affinity of the perfluorinated azulene is 2.6 eV or about 0.2 eV per fluorine atom. 

Hecht, S.S., Amin, S., Melkikian, A.A., LaVoie, E.J., and Hoffmann, D. (1985) Effects of methyl and fluorine substitution on the metabolic activation and tumorigenidty of polycyclic aromatic hydrocarbons, in Polycyclic Hydrocarbons and Carcinogenesis (ed. 

Since all sample manipulations are associated with the loss of analytes, internal standards are usually added to the sample before workup. In polycyclic aromatic carbon (PAC) work with mass spectrometric methods, deuterated aromatics have long been used for this purpose. Fluorinated PACs also offer several advantages. Andersson et al. used 5-fluorobenzothiophene for benzothiophenes and 2-fluorodibenzothiophene for three-ring PAHs. These fluoroderivatives were chosen because they are well separated from other sample constituents typically occurring in complex oil samples and because they show suitable elution characteristics in the various separation steps of sample workup. 

Polycyclic aromatic hydrocarbons Partially hydrogenated aromatic hydrocarbons Perfluorohydrocarbons (Totally fluorinated hydrocarbons)... 

NMR spectra including long-range proton-proton, proton-fluorine and carbon-fluorine couplings have been measured by Lutnaes et in order to characterize a series of monofluorinated polycyclic aromatic compounds such as 1-fluoronaphtalene, 2-fluorophenantrene,l-fluoropyrene and some others. 

Dehydrogenation reactions of ketones have been applied to the aromatization and oxidative coupling of polycycles. High temperature dehydrogenation of 7-fluoro-3,4-dihy-dronaphthalen-l(2/7)-onc with sulfur gives 7-fluoro-1-naphthol in 90% yield.196 During the oxidation of fluorinated anthraccn-9(10//)-one 9 with iron(III) chloride, a radical is formed that collapses by a termination reaction to give the bianthryl derivative 10.197... 

Prins summarizes advances in understanding of the reactions in catalytic hydrodenitrogenation (HDN), which is important in hydroprocessing of fossil fuels. Hydroprocessing is the largest application in industrial catalysis based on the amount of material processed. The chapter addresses the structures of the oxide precursors and the active sulfided forms of catalysts such as Ni-promoted Mo or W on alumina as well as the catalytically active sites. Reaction networks, kinetics, and mechanisms (particularly of C-N bond rupture) in HDN of aliphatic, aromatic, and polycyclic compounds are considered, with an evaluation of the effects of competitive adsorption in mixtures. Phosphate and fluorine promotion enhance the HDN activity of catalysts explanations for the effect of phosphate are summarized, but the function of fluorine remains to be understood. An account of HDN on various metal sulfides and on metals, metal carbides, and metal nitrides concludes this chapter. 

The word oil is used for an organic phase that is essentially immiscible with water and is thus relatively apolar. It can refer to a hydrocarbon, a partially or totally chlorinated or fluorinated hydrocarbon, single-chain alkane, cyclic or aromatic hydrocarbon, polar monoester such as ethyl oleate, long-chain alcohol such as dodecanol, triglyceride natural oil, or polycyclic cholesterol. The most typical oil phase is, of course, n-alkane, which would be characterized by its length or alkane carbon number (ACN). 

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