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Acenaphthene hydrogenation

This article deals mainly with naphthalene [91-20-3]. The hydrogenated naphthalenes, the alkylnaphthalenes (particularly methyl- and isopropylnaphthalenes), and acenaphthene also are discussed (see also Naphthalenederivatives). [Pg.480]

The anhydride can be made by the Hquid-phase oxidation of acenaphthene [83-32-9] with chromic acid in aqueous sulfuric acid or acetic acid (93). A postoxidation of the cmde oxidation product with hydrogen peroxide or an alkaU hypochlorite is advantageous (94). An alternative Hquid-phase oxidation process involves the reaction of acenaphthene, molten or in alkanoic acid solvent, with oxygen or acid at ca 70—200°C in the presence of Mn resinate or stearate or Co or Mn salts and a bromide. Addition of an aHphatic anhydride accelerates the oxidation (95). [Pg.503]

Preferential elimination of hydrogen fluonde from vicinal halofluoro compounds occurs also in the cyclohexane series [55 56, 57], acenaphthene series [55], and benzodihydrofuran series [59 60] Here, the strength of the base and the stereochemistry play important roles... [Pg.896]

Contaminated soil from a manufactured coal gas plant that had been exposed to crude oil was spiked with acenaphthene (400 mg/kg soil) to which Fenton s reagent (5 mL 2.8 M hydrogen peroxide 5 mL 0.1 M ferrous sulfate) was added. The treated and nontreated soil samples were incubated at 20 °C for 56 d. Fenton s reagent did not promote the mineralization of acenaphthene by indigenous microorganisms to any appreciable extent. The mineralization of acenaphthene was enhanced only 1.2-fold when compared with the nontreated control sample. The amounts of acenaphthene recovered as carbon dioxide after treatment with and without Fenton s reagent were 20 and 17%, respectively (Martens and Frankenberger, 1995). [Pg.48]

Hydrindene, see Indan Hydrindonaphthene, see Indan 1,8-Hydroacenaphthylene, see Acenaphthene Hydrobroinic ether, see Ethyl bromide Hydrocarbon propellant A-17, see Bntane Hydrochloric ether, see Chloroethane Hydrofuran, see Tetrahydrofuran Hydrogen carboxylic acid, see Formic acid Hydrophenol, see Cyclohexanol Hydroqninol, see Hydroquinone Hydroqninole, see Hydroquinone a-Hydroqninone, see Hydroquinone p-Hydroqninone, see Hydroquinone 6-Hydroxyacenaphthenone, see Acenaphthene Hydroxybenzene, see Phenol... [Pg.1491]

Hydrogenation of acenaphthylene During the experiment, a great deal of polymerisation occurred and only the acetone-soluble part of the product was analysed. This contained 18 wt % acenaphthene, 62 wt % dimethylnaphthalenes and 20 wt % other material. An experiment carried out at 300°C also showed considerable polymerisation with a similar distribution of material in the acetone-soluble fraction in both experiments, no starting material was identified in the product The majore product was 1.9-dimetiiylnaphthalene and the other material showed GC peaks with retention times from tetralin to methyltetralin. [Pg.243]

Double bonds conjugated with benzene rings are reduced electrolytically [344] (p. 23). Where applicable, stereochemistry can be influenced by using either catalytic hydrogenation or dissolving metal reduction [401] (p. 24). Indene was converted to indane by sodium in liquid ammonia in 85% yield [402] and acenaphthylene to acenaphthene in 85% yield by reduction with lithium aluminum hydride in carbitol at 100° [403], Since the benzene ring is not inert toward alkali metals, nuclear reduction may accompany reduction of the double bond. Styrene treated with lithium in methylamine afforded 25% of 1-ethylcyclohexene and 18% of ethylcyclohexane [404]. [Pg.49]

Acenaphthylene heated with lithium aluminum hydride in carbitol at 120° gave 97% yield of acenaphthene [403], Anthracene is reduced very easily to the 9,10-dihydro compound by catalytic hydrogenation [78] and by sodium... [Pg.51]

Benzil forms an adduct with acenaphthene when a mixture of the two is irradiated in benzene solution, presumably by cross coupling of the radicals produced by abstraction of a hydrogen atom from acenaphthene by ben-zii 12,13,66 xhe other products of this reaction were not reported. [Pg.87]

The hydrogenation of aromatics (benzene, toluene, a-methylstyrene) can be carried out under very low (1 12,000) catalyst substrate ratio, and mild conditions on Rh and Ni organometallic complexes anchored to USY zeolites.474 A Rh complex anchored to functionalized MCM-41 exhibits excellent performance in the hydrogenation of arenes (benzene, toluene, p-xylene, mesitylene) under mild conditions (45°C and 1 atm) 475 A uniquely selective hydrogenation of acenaphthene and acenaphthylene was performed by using a triruthenium carbonyl cluster 476... [Pg.675]

This reaction was first observed by Plate, Erivanskaya, and Khalima-Mansur over platinum-on-carbon and platinum-on-alumina catalysts (43-48). Platinum-on-carbon catalyzes this reaction between 310°C and 390°C (above which the catalyst is poisoned) (44). Over an acidic platinum-alumina catalyst containing 0.5 wt% platinum and 0.1 wt% sodium, 16.7% acenaphthenes and 1.5% acenaphthylene are obtained at 460°C and at 0.4 liquid hourly space velocity in hydrogen diluent. Conversions are considerably lower in helium. [Pg.315]

Kinetic studies at short residence times first suggested the following reaction sequence ethylnaphthalene dehydrogenates to vinylnaphthalene vinylnaphthalene dehydrocyclizes to acenaphthylene and finally acenaphthylene is hydrogenated to acenaphthene. However, further work by Isagulyants and co-workers, using 14C-labeled 1-vinylnaphthylene, shows that over platinum on alumina at 470°C, acenaphthene and acenaphthylene are formed from both 1-ethylnaphthalene and 1-vinylnaphthalene. Vinylnaphthalene dehydrocyclizes about three times faster than ethylnaphthalene. The vinylnaphthalene intermediate remains adsorbed on the catalyst surface during the reaction (48). [Pg.316]

Solvated metal atoms can be dispersed in excess organic solvent at low temperature and used as a source of metal particles for the preparation of both unsupported metal powders and supported metal catalysts158,161. Alternatively, metal vapor is condensed into a cold solution of a stabilizing polymer to form crystallites of the order 2-5 nm in diameters159. Equation 17 illustrates the unique activity of a colloidal Pd catalyst in the partial hydrogenation of acenaphthene. [Pg.859]

The elimination of hydrogen is very common in plasmas. Dehydrogenation of compounds like tetraline, acenaphthene, tetrahydroquinoline or in-dane has been carried out with excellent results. Elimination of hydrogen... [Pg.47]

Reaction network for the hydrodesulfurization of dibenzothiophene and for the hydrogenation of acenaphthene and biphenyl... [Pg.75]

There seems no reason why any of the mechanisms discussed in Sections 3.4-3.6 cannot function in the conversion of alkynes to alkenes. The alkene route of hydrogenation is frequently encountered because alkynes complex more strongly to transition metals than alkenes and their complexes are formed preferentially in competition with the oxidative addition of dihydrogen. Internal alkynes coordinate to bis(arylimino)acenaphthene complexes of palladium and the fricoordinate species activate molecular hydrogen. Transfer of both atoms of hydrogen forms... [Pg.1641]

Removing hydrogen atoms from adjacent carbon atoms, as shown above for stilbene, is generally difficult synthetically. Preliminary work (28) has shown that dianions of acenaphthalene can be prepared by treating acenaphthene with n-BuLi in THF. Unfortunately the technique has limited applicability—for example, similar treatment of 9,10-dihydrophenanthrene does not give dianion formation (28). We have routinely used a modified version of this reaction with the base TMED for years (24, 25)—as above in the synthesis of naphthalene dianion. The dianion of phenanthrene with TMED can also be readily prepared by this reaction ... [Pg.68]

The fraction seven FIMS plot (Figure 4) exhibits aromatic hydrocarbons with lower hydrogen contents. The two major series present in this fraction are acenaphthenes and fluorenes, but methyl phenanthrene or anthracene (m/e = 192) is also a significant component of fraction seven. [Pg.244]

A summary of the hydrocarbon series in the nine DFM and five JP-5 LC fractions are listed in Tables V and VI. The data are qualitative in nature and based on both MS techniques, El and FI. The trends with fraction number are as expected, hydrocarbons with less hydrogen appear in the later fractions. Further, the trend in aromatic ring size was 1 ring (fraction 3), 2 rings (fraction 4), and 3 rings (fractions 5-9). The JP-5 has very little three ring material but the DFM exhibits evidence for considerable amounts of acenaphthenes, fluorenes, and phenanthrenes/ anthracenes. [Pg.244]

A good and comprehensive review of catalytic electrophilic acylation was published by Pearson and Buehler.i Only the catalysts most widely used were considered, with special attention to iron trichloride, zinc chloride, iodine, and elemental iron. The substrates that can be acylated using small amounts of catalysts include alkylarenes, aryl ethers, biphenyls, naphthalenes, acenaphthenes, fluorene, furans, and thiophenes. Aromatic acyl chlorides lead to better yields than aliphatic ones, reaching a maximum of 96% and a minimum of 34%. In general, fhe reactions are performed af relatively high temperatures (from 50°C to 200°C) af which hydrogen chloride evolution is fairly rapid. [Pg.33]

Acenaphthenyl methyl ketone (2 g) is heated with purified dioxan (8 g) and a solution of sulfur (1 g) in ammonium sulfide solution [10 g prepared by saturating ammonia solution 0/0.88) with hydrogen sulfide] in a sealed tube at 160° for 12 h. The crude 1-acenaphthene-acetamide produced is hydrolysed by 4 hours boiling with 15% sodium hydroxide solution (50 ml), giving a 57 % overall yield of the acid. [Pg.1060]


See other pages where Acenaphthene hydrogenation is mentioned: [Pg.487]    [Pg.81]    [Pg.464]    [Pg.243]    [Pg.5]    [Pg.663]    [Pg.4]    [Pg.574]    [Pg.76]    [Pg.175]    [Pg.7]    [Pg.281]    [Pg.175]    [Pg.953]    [Pg.959]    [Pg.311]    [Pg.2295]    [Pg.3]    [Pg.239]    [Pg.73]    [Pg.53]    [Pg.140]    [Pg.235]    [Pg.24]    [Pg.5]    [Pg.6]   
See also in sourсe #XX -- [ Pg.68 ]




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