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Naphthalene-anthracene

Complex Alkanes Aromatic e g.Naphthalene, Anthracene, Naphthenes J... [Pg.95]

Benzene, toluene, naphthalene, anthracene, phenanthrene, biphenyl, petroleum. [Pg.393]

The theory of sublimation, t.e. the direct conversion from the vapour to the sohd state without the intermediate formation of the liquid state, has been discussed in Section 1,19. The number of compounds which can be purified by sublimation under normal pressure is comparatively small (these include naphthalene, anthracene, benzoic acid, hexachloroethane, camphor, and the quinones). The process does, in general, yield products of high purity, but considerable loss of product may occur. [Pg.154]

Naphthalene, anthracene, carbazole [86-74-8] phenol [108-95-2] and cresyUc acids are found in the tar. Phenol and cresyUc acids are useful as chemical and resin intermediates. The aromatic chemicals are useful in the manufacture of pharmaceuticals, dyes, fragrances, and pesticides. Various grades of pitch are made from residues of tar refining. Coal-tar pitch is used for roofing and road tar, and as a binder mixed with petroleum coke to produce anodes for the aluminum industry. [Pg.162]

Eused-ring polycycHc fluoroaromatics can be made from the corresponding amino fused-ring polycycHc or from preformed fluoroaromatics, eg, 4-fluorophenyl-acetonitrile [459-22-3] (275). Direct fluorination techniques have been successfully appHed to polycycHc ring systems such as naphthalene, anthracene, benzanthracenes, phenanthrene, pyrene, fluorene, and quinoHnes with a variety of fluorinating agents xenon fluorides (10), acetyl hypofluorite (276), cesium fluoroxysulfate (277), and electrochemical fluorination (278,279). [Pg.328]

Dyes, Dye Intermediates, and Naphthalene. Several thousand different synthetic dyes are known, having a total worldwide consumption of 298 million kg/yr (see Dyes AND dye intermediates). Many dyes contain some form of sulfonate as —SO H, —SO Na, or —SO2NH2. Acid dyes, solvent dyes, basic dyes, disperse dyes, fiber-reactive dyes, and vat dyes can have one or more sulfonic acid groups incorporated into their molecular stmcture. The raw materials used for the manufacture of dyes are mainly aromatic hydrocarbons (67—74) and include ben2ene, toluene, naphthalene, anthracene, pyrene, phenol (qv), pyridine, and carba2ole. Anthraquinone sulfonic acid is an important dye intermediate and is prepared by sulfonation of anthraquinone using sulfur trioxide and sulfuric acid. [Pg.79]

Many different combinations of carboxyflc acid and hydroxyl groups have been tested to form LCPs. An aromatic stmcture (ben2ene, naphthalene, anthracene, etc) is required that has its functional groups symetricaHy arranged on opposite sides of the molecule. Examples are a 1,4-substituted ben2ene compound or 2,6-substituted naphthalene compound. These monomers are often complex and expensive molecules and account for a significant portion... [Pg.274]

The polycyclic aromatic hydrocarbons such as naphthalene, anthracene, and phenan-threne undergo electrophilic aromatic substitution and are generally more reactive than benzene. One reason is that the activation energy for formation of the c-complex is lower than for benzene because more of the initial resonance stabilization is retained in intermediates that have a fused benzene ring. [Pg.568]

This cyclization also gives good results in the case of derivatives of naphthalene, anthracene, phenanthrene, and other aromatic substrates [76]... [Pg.953]

Another class of compounds is called condensed-ring or fused-ring systems. These structures contain two or more aromatic rings that share a pair of carbon atoms. Examples include naphthalene, anthracene, and phenanthrene, the latter two being isomeric structures. [Pg.312]

Some additional derivatives containing extended 7t-systems in place of the benzene nucleus are naphthalene, anthracene (2,3-Ac) and phenanthrene (9,10-Phc). They also belong to the phthalocyanine family. For the naphthalene system two types of macrocyclcs, the 1,2-naph-thalocyanine (1,2-Nc) and the 2,3-naphthalocyanine (2,3-Nc), are known. [Pg.718]

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-... [Pg.153]

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. [Pg.607]

Naphthalene, anthracene, and other condensed ring systems... [Pg.134]

A. in naphthalene, anthracene and phenanthrene, this value being somewhat larger than the benzene value (1.39 A.). With increase in size of the hydrocarbon the carbon-carbon distances should all approach the graphite value... [Pg.207]

Experiments using marine sediment slurries have examined the effect of pre-exposure to various aromatic hydrocarbons on the rate of subsequent degradation of the same, or other hydrocarbons. The results clearly illustrated the complexity of the selection process for example, whereas pre-exposure to benzene, naphthalene, anthracene, or phenanthrene... [Pg.216]

This chapter focuses on recent developments in the design and applications of fluorescent organic markers, such as coumarins, benzoxadiazoles, acridones, acridines, polyaromatics (naphthalene, anthracene, and pyrene), fluorescein, and rho-damine derivatives, which display maximum fluorescence emission in the UV/ visible region and have been applied in the labeling of relevant biomolecules, namely DNA, RNA, proteins, peptides, and amino acids, among others. [Pg.27]

Polycyclic aromatic compounds, namely naphthalene, anthracene and pyrene derivatives are widely used as fluorescent probes in relevant biomolecules. [Pg.38]

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... [Pg.17]

Type 61b of the intensely colored quinocyclopropenes is represented by the di-cyanomethylene species 115 and 118 of p- and o-quinonoid structure. In addition to the systems 115,119, and 122 reported by Gompper1001 a series of o- and p-quino-cyclopropenes in the benzene, naphthalene, anthracene, phenanthrene, and fluorene series (718-125) were prepared75) carrying the bis-(p-anisyl)-cyclopropenyl residue, which brings about a better stabilization of the cyclopropenium moiety101 ... [Pg.27]

When two or more benzene rings are fused together to give naphthalene, anthracene, etc., X-ray diffraction studies show that some localization of double bonds occurs (22-24) this affects the chemical reactivities of different regions in the molecule. The experimentally measured bond lengths in PAHs are those that would be expected from a consideration of the various types of resonance hybrids (25) that are possible. [Pg.133]

Although organic anion radicals are oxygen sensitive, they have been isolated as crystalline salts from a variety of electron acceptors (e.g., chloranil, tetracyanoethylene, tetracyanoquinodimethane, perylene, naphthalene, anthracene, tetraphenylethylene, etc.) and their structures have been established by X-ray crystallography.180... [Pg.245]

Photochemical osmylation. The irradiation of the charge-transfer bands (Fig. 13) of the EDA complex of 0s04 with various benzenes, naphthalenes, anthracenes, and phenanthrene yields the same osmylated adducts as obtained in the thermal reactions. For example, irradiation of the purple solution of anthracene and 0s04 in dichloromethane at k > 480 nm yields the same 2 1 adduct (B) together with its syn isomer as the sole products, i.e.,... [Pg.273]

B. Tetranitromethane. Tetranitromethane forms colored charge-transfer (CT) complexes with a variety of organic donors such as substituted benzenes, naphthalenes, anthracenes, enol silyl ethers, olefins, etc. For example, an orange solution is instantaneously obtained upon exposure of a colorless solution of methoxytoluene (MT) to tetranitromethane (TNM),237 i.e.,... [Pg.283]

A general theory of the aromatic hydrocarbon radical cation and anion annihilation reactions has been forwarded by G. J. Hoytink 210> which in particular deals with a resonance or a non-resonance electron transfer mechanism leading to excited singlet or triplet states. The radical ion chemiluminescence reactions of naphthalene, anthracene, and tetracene are used as examples. [Pg.135]

Nelson, O.A., Senseman, C.E. (1922) Vapor pressure determinations on naphthalene, anthracene, phenanthrene, and anthraquinone between their melting and boiling points. Ind. Eng. Chem. 14, 58-62. [Pg.912]

Schwarz, F.P., Wasik, S.P. (1976) Fluorescence measurements of benzene, naphthalene, anthracene, pyrene, fluoranthene, and benzo[a]pyrene in water. Anal. Chem. 48, 524—528. [Pg.915]


See other pages where Naphthalene-anthracene is mentioned: [Pg.434]    [Pg.531]    [Pg.425]    [Pg.434]    [Pg.312]    [Pg.123]    [Pg.590]    [Pg.294]    [Pg.189]    [Pg.49]    [Pg.860]    [Pg.76]    [Pg.398]    [Pg.178]    [Pg.327]    [Pg.321]    [Pg.55]    [Pg.195]    [Pg.306]    [Pg.287]    [Pg.57]   
See also in sourсe #XX -- [ Pg.410 ]




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Substituted Benzenes, Naphthalenes, and Anthracenes

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