Fluoranthene anion

The difference in the electron affinity between light and heavy isotopic isomers is, in other words, the difference in the stability of their anion-radicals. Such a difference gives a valuable tool for use in probing the chemistry of anion-radicals. The difference in the stability of the ring-deuterated and ring-nondeuterated arene anion-radicals has been employed to examine the transition states for the one-electron-promoted cleavage of naphthyl methyl phenyl ether and naphthyl benzyl ether (Guthrie and Shi 1990). In this reaction, the potassium salt of fluoranthene anion-radical was an electron donor ... 

Freed and Faulkner (1972) have deduced that the monocation dimer of N-mcthylphenothiazine (N-MP) affects the yield of triplet states in the chemiluminescent oxidation of fluoranthene anion radical (FA -) by N-MP + [eqns (91) and (92)]. The triplet yields... 

This ion trap instrument has a chemical ionization source located orthogonally to an octopole ion guide, which admits fluoranthene anions formed in the chemical ionization source and transmits them to the entrance of the end-cap electrode [42], The positive polypeptide ions produced from ESI are admitted axially to the ion trap through the octopole ion guide and the entrance of the end-cap electrode. 

The first reported use of the ETD/PTR scan type involved reactions between cation precursors with radical fluoranthene anions (ETD), followed by reactions of cationic ETD product ions with benzoic acid anions (PTR) (Figure 3.6) [77]. These... 

A means to deposit energy in multiply charged cation complexes is by the exothermic addition of an electron. The technique of electron transfer dissociation (ETD) employs as an electron donor the polycyclic aromatic hydrocarbon fluoranthene anion, CieHio , the electron binding energy for which is only 0.6 eV. An important characteristic of ETD when applied to metal ion complexes is that the process results in both charge reduction and chemi-... 

Chemically inert triplet quenchers e.g. trans-stilbene, anthracene, or pyrene, suppress the characteristic chemiluminescence of radical-ion recombination. When these quenchers are capable of fluorescence, as are anthracene and pyrene, the energy of the radical-ion recombination reaction is used for the excitation of the quencher fluorescence 15°). Trans-stilbene is a chemically inert 162> triplet quencher which is especially efficient where the energy of the first excited triplet state of a primary product is about 0.2 eV above that of trans-stilbene 163>. This condition is realized, for example, in the energy-deficient chemiluminescent system 10-methyl-phenothiazian radical cation and fluoranthene radical anion 164>. 

Fig. 14 Reduction of PhjCSPh by electrochemically generated aromatic anion radicals (in DMF at 25°C). Variation of the rate-determining step rate constant, A , with the standard potential of the aromatic anion radical, p,g (from left to right azobenzene, benzo[c]cinnoline, 4-dimethylaminoazobenzene, terephthalonitrile, naphthacene, phlhalonitrile, perylene, fluoranthene, 9,10-diphenylanthracene). The dotted lines are the theoretical limiting behaviours corresponding to the concerted (right) and stepwise (left) pathways. (Adapted from Severin et al 1988.)...

Figure 4.2 Top down mass spectromet using ETD. (a) Setup of ETD and PTR in a 3D HCTultra ion trap (BDaltonics). ETD and PTR reactants are ionized in an additional nCI source and injected into the transfer line from the same reservoir. Switching nCI parameters decides whether the radical anion for ETD (fluoranthene) or its derivative, a basic anion, for PTR (CieHn ) is extracted from...

Irradiation of the sultone (194) in methanol affords the ring-opened products (195) and (196). Subsequent irradiation of these compounds brings about elimination of the S03Me group and formation of the fluoranthene (197). This compound is thought to be the result of cyclization within the anion (198). 

Recently Compton and Northing have described a method for the measurement of N2O in acetonitrile [51], They have shown that N2O reacts with the radical anion of the organic compound fluoranthene (Figure 10). Fluoranthene is reduced on mercury plated copper electrodes at potentials more negative than 1.5V (vs SCE). The reaction in the presence of N2O is a classical EC or catalytic mechanism, ie. 

Compton and coworkers have investigated the mediated reduction of isoflurane on mercury by the radical anion of fluoranthene [59]. Figure 16 shows RDE voltammograms for the reduction of fluoranthene in the presence of increasing amounts of isoflurane. As can be seen the current increases with isoflurane concentration. 

Z (a,c) = 104°) and contains two fluoranthene molecules per unit cell. They are stacked along the a axis with two alternating spacings (0.328 nm and 0.333 nm). Two each of the fluoranthene molecules form the radical cation (Fa)2 PFg. The stacking axis a is perpendicular to the planes of the fluoranthene molecules. The PFg anions are located in the channels between the fluoranthene molecules. From [10]. 

There are a large number of strong CT complexes or radical-ion salts. Many organic compounds can be oxidised to radical cations by a suitable partner (e.g. perylene) or reduced to radical anions (e.g. TCNQ ".) Figure 9.12 shows a variety of such molecules. The complexes can consist of two organic molecules, as in the case of TTF-TCNQ. One of the partners can however also be an inorganic ion, e.g. Cu+ in (2,5-Dimethyl-DCNQI)2 Cu or also Ag", Li+, Cs+, Na", K+, Rb+ (see Sect. 9.5) or PF, as in the radical-cation salt (fluoranthene)J PF (see Sect. 9.6). 

ETD is used with QqQ, QTOF, and orbitrap instruments. Reagent species, such as fluoranthene and nitrosobenzene, are activated by conversion to their respective radical anions in a corona discharge. The radicals are then mixed with the analyte (that has been ionized using ESI), resulting in the transfer of an electron from the reagent to the analyte. The acquired energy promotes fragmentation pathways that are different, shown in Section 3.5.1.5, from those seen in CID. 

Mote recently, ETD, a dissociation technique very similar to ECD, was introduced for peptide/protein sequencing [56-58]. In ETD, multiply-chaiged cations react with an anion radical (A, e.g., SO2, SFg", anthracene, fluoranthene), leading to electron transfer and the generation of both odd- and even-electron fragments and molecular species with lower charge states as follows ... 

Reductive Remediation of Nonhalogenated Molecules. Na/NHa treatments can also destroy nonhalogenated hazardous conqraunds. Three classes pollutants will be mentioned here polynuclear aromatic hydrocarbons (PNAs), nitro- and nitrate-type explosive wastes and chemical warfare agents. The treatment of neat sanq>les of PNAs leads to destmction efficiencies of 99.99% for many of these conq)ounds including such examples as acenaphthene, benzo[a]anthracene, benzo[b]fluoranthene, benzo[g,h,l]perylene, chrysene, fluorandiene, fluorine, naphdialene and phenanthrene. With the exception of naphthalene and anthracene, conq)lex product mixtures are formed. Radical anion formation followed by protonation occurs sequentially leading to dihydro, tetrahydro and further reduced products (see Scheme 3). Depending on the reaction conditions, dimerization of intermediate radicals can occur to give dimers in various states of reduction. 

The simplest organic metals can in fact be produced starting from naphthalene and similar arenes such as pyrene, perylene, fluoranthene or triphenylene. 4-16 if these compounds are electro-chemically oxidized in an otherwise inert solvent containing a supporting electrolyte with anions of low nucleophili city, coloured crystals of high conductivity will grow at the anode. These crystals... 

The one-electron reduction of 3mM fluoranthene, FI, to its radical anion was studied in acetonitrile solution containing 0.1 M tetrabutylammonium perchlorate as supporting electrolyte, using a mercury-plated rotating disc electrode of... 

Anthracene radical anions as obtained by electron capture in a chemical ionization source with methane reagent gas were formerly employed as anions [160,163]. Meanwhile, fluoranthene has become more widely used (Scheme 9.1) [164,165]. 

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