Sodium anthracene

The reactivities of the stoichiometric EDA complexes of anthracene with sodium were also studied (d). It is known that there are two species in the anthracene-sodium EDA complex, 1 1 and 1 2 complexes, the former consisting of mononegative anthracene and the latter, dinegative anthracene. 

When hydrogen was admitted to the anthracene-sodium complexes, hydrogen chemisorption over the complexes took place slowly below 100°. The chemisorption continued for a few days, and it was difficult to reach the equilibrium value. 

Scintillation detectors are substances which fluoresce when stmck by x-radiation. Scintillation can, therefore, serve to convert x-ray photons into visible or ultraviolet light. Scintillation materials include thaUium-activatedcrystals of sodium iodide, NaI(Tl), potassium iodide, KI(T1), or cesium iodide, CsI(Tl) crystals of stilbene (a, P-diphenylethylene) [588-59-0] and anthracene [120-12-7] bismuth germanium oxide [12233-56-6] ... 

The addition product, C QHgNa, called naphthalenesodium or sodium naphthalene complex, may be regarded as a resonance hybrid. The ether is more than just a solvent that promotes the reaction. StabiUty of the complex depends on the presence of the ether, and sodium can be Hberated by evaporating the ether or by dilution using an indifferent solvent, such as ethyl ether. A number of ether-type solvents are effective in complex preparation, such as methyl ethyl ether, ethylene glycol dimethyl ether, dioxane, and THF. Trimethyl amine also promotes complex formation. This reaction proceeds with all alkah metals. Other aromatic compounds, eg, diphenyl, anthracene, and phenanthrene, also form sodium complexes (16,20). 

Hydrogen and sodium do not react at room temperature, but at 200—350°C sodium hydride is formed (24,25). The reaction with bulk sodium is slow because of the limited surface available for reaction, but dispersions in hydrocarbons and high surface sodium react more rapidly (7). For the latter, reaction is further accelerated by surface-active agents such as sodium anthracene-9-carboxylate and sodium phenanthrene-9-carboxylate (26—28). 

Has been purified by co-distillation with ethylene glycol (boils at 197.5°), from which it can be recovered by additn of water, followed by crysm from 95% EtOH, benzene, toluene, a mixture of benzene/xylene (4 1), or EtjO. It has also been chromatographed on alumina with pet ether in a dark room (to avoid photo-oxidation of adsorbed anthracene to anthraquinone). Other purification methods include sublimation in a N2 atmosphere (in some cases after refluxing with sodium), and recrystd from toluene [Gorman et al. J Am Chem Soc 107 4404 1985]. 

Benz[a]anthracene [56-55-3] M 228.3, m 159-160". Crystd from MeOH, EtOH or benzene (charcoal), then chromatographed on alumina from sodium-dried benzene (twice), using vacuum distn to remove benzene. Final purification was by vacuum sublimation. 

Naphthacene (benz[b]anthracene, 2,3-benzanthracene, rubene) [92-24-0] M 228.3, m >300 , 341 (open capillary), 349 , 357 . Crystd from EtOH or benzene. Dissolved in sodium-dried benzene and passed through a column of alumina. The benzene was evaporated under vacuum, and the chromatography was repeated using fresh benzene. Finally, the naphthacene was sublimed under vacuum. [Martin and Ubblehode J Chem Soc 4948 7967.] Also recrysts in orange needles from xylene and sublimes in vacuo at 186°. [UV Chem Ber 65 517 1932, 69 607 7956 IR Spectrochim Acta 4 373 7957.]... 

Aryl bromides were also perfluoroethylated under these conditions [205] The key to improved yields was the azeotropic removal of water from the sodium perfluoroalkylcarboxylate [205] Partial success was achieved with sodium hepta-fluorobutyrate [204] Related work with halonaphthalene and anthracenes has been reported [206 207] The main limitation of this sodium perfluoroalkylcarboxylate methodology is the need for 2 to 4 equivalents of the salt to achieve reasonable yields A trifluoromethylcopper solution can be prepared by the reaction of bis(tri-fluoromethyl)mercury with copper powder in /V-methylpyrrolidone (NMP) at 140 °C [208] (equation 138) or by the reaction of N-trifluoromethyl-A-nitro-sotnfluoromethane sulfonamide with activated copper in dipolar aprotic solvents [209] This trifluoromethylcopper solution can be used to trifluoromethylate aro matic [209], benzylic [209], and heterocyclic halides [209]... 

Properties. Orange needles m. p. 2Sc>—290 tsuhlinit-completely at 140 without decomposition soluble in alkali with a deep purple coloui (sodium alizarate).. It is i-ocluced t( anthracene on heating with diy zinc dust. 

Electron transfer reactions involving alkali metals are heterogeneous, and for many purposes it is desirable to deal with a homogeneous electron transfer system. It was noticed by Scott39 that sodium and other alkali metals react rapidly with aromatic hydrocarbons like diphenyl, naphthalene, anthracene, etc., giving intensely colored complexes of a 1 to 1 ratio of sodium to hydro-... 

An interesting reaction of dimsyl anion 88 is the methylation of polyaromatic compounds. Thus naphthalene, anthracene, phenanthrene, acridine, quinoline, isoquinoline and phenanthridine were regiospecifically methylated upon treatment with potassium t-butoxide and DMSO in digyme or with sodium hydride in DMSO123-125. Since ca. 50% of D was found to remain in the monomethyl derivative 93 derived from 9-deuteriophenanthrene 92, the mechanistic route shown in Scheme 2 was suggested125. 

The column used was a Pecosphere 3 mm in diameter and 3 cm long carrying a Cl8 stationary phase. The mobile phase was a mixture of methanol (75%) and water (25%) at a flow rate of 2 ml/min. The solutes were 1 benzene, 2 toluene, 3 ethyl benzene, 4 isopropyl benzene, 5 t-butylbenzene, 6 anthracene, and 7 sodium chloride. 

Table 6.2 Sodium and guanidinium salt effects (relative reaction rates) of Diels-Alder reaction of anthracene-9-carbinol and N-ethylmaleimide...

Increased removal of phenanthrene from soil columns spiked with the rhamnolipid mixture synthesized by Pseudomonas aeruginosa UG2 has been demonstrated, and shown to depend both on the increased desorption of the substrate and on partitioning into micelles (Noordman et al. 1998). However, the addition of the biosurfactant from the same strain of Pseudomonas aeruginosa UG2 or of sodium dodecyl sulfate had no effect on the rate of biodegradation of anthracene and phenanthrene from a chronically contaminated soil. 

Figure 17.7 Electrocatalysis of O2 reduction by Pycnoporus cinnabarinus laccase on a 2-aminoanthracene-modified pyrolytic graphite edge (PGE) electrode and an unmodified PGE electrode at 25 °C in sodium citrate buffer (200 mM, pH 4). Red curves were recorded immediately after spotting laccase solution onto the electrode, while black curves were recorded after exchanging the electrochemical cell solution for enzyme-fiiee buffer solution. Insets show the long-term percentage change in limiting current (at 0.44 V vs. SHE) for electrocatalytic O2 reduction by laccase on an unmodified PGE electrode ( ) or a 2-aminoanthracene modified electrode ( ) after storage at 4 °C, and a cartoon representation of the probable route for electron transfer through the anthracene (shown in blue) to the blue Cu center of laccase. Reproduced by permission of The Royal Society of Chemistry fi om Blanford et al., 2007. (See color insert.)...

NH3 Naphth2). If sodium is used in place of potassium, the product detonates as crystallisation starts. This is attributed to energetic expulsion of ammonia held endothermically in the growing crystal lattice. The same also occurs with anthracene and sodium, and nitrobenzene and barium. Caution in preparing and using these compounds is urged. 

Compounds of this type may only be isolated in the presence of suitable donor molecules, among those, diglyme has been used frequently, but other examples include TMEDA or 2,2,1-crypt for sodium.150 The reduction of naphthalene or anthracene with sodium in diglyme affords separated ions with the radical anion [Na(diglyme)2][naphthalene/anthracene] 139, 140.151... 

Other selected examples include tris(tetramethylethylene diamine-sodium)-9,9-dianthryl 143,154 alkali metal salts of 9,10-bis(diisopropylsilyl)anthracene 144,155 as well as the closely related naked 9,10-bis(trimethylsilyl)anthra-cene radical anion 145.156 This chemistry is further extended to the solvent-shared and solvent-separated alkali metal salts of perylene radical anions and dianions 146, 147,156 while other examples focus on alkali metal salts of 1,2-diphenylbenzene and tetraphenylethylene derivatives, where reduction with potassium in diglyme afforded contact molecules with extensive 7r-bonding, [l,2-Ph2C6H4K(diglyme)] 148.157 Extensive 7r-coordination is also observed in (1,1,4,4 tetraphenylbutadiene-2,3-diyl)tetracesiumbis(diglyme)bis(methoxyethanolate) 149.158... 

Sodium anthracene-9-carboxylate, 22 765 Sodium antimonide, 3 54, 3 58 Sodium ascorbate, 25 804... 

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