Oxidized naphthalene

Benzoquinone ( quinone ) is obtained as the end product of the oxidation of aniline by acid dichromate solution. Industrially, the crude product is reduced with sulphur dioxide to hydroquinone, and the latter is oxidised either with dichromate mixture or in very dilute sulphuric acid solution with sodium chlorate in the presence of a little vanadium pentoxide as catalyst. For the preparation in the laboratory, it is best to oxidise the inexpensive hydroquinone with chromic acid or with sodium chlorate in the presence of vanadium pent-oxide. Naphthalene may be converted into 1 4-naphthoquinone by oxidation with chromic acid. 

Oxidation. Naphthalene may be oxidized direcdy to 1-naphthalenol (1-naphthol [90-15-3]) and 1,4-naphthoquinone, but yields are not good. Further oxidation beyond 1,4-naphthoquinone [130-15-4] results in the formation of ortho- h. h5 ic acid [88-99-3], which can be dehydrated to form phthaUc anhydride [85-44-9]. The vapor-phase reaction of naphthalene over a catalyst based on vanadium pentoxide is the commercial route used throughout the world. In the United States, the one phthaUc anhydride plant currently operating on naphthalene feedstock utilizes a fixed catalyst bed. The fiuid-bed process plants have all been shut down, and the preferred route used in the world is the fixed-bed process. 

Gibbs A process for oxidizing naphthalene to phthalic anhydride, using air as the oxidant and catalyzed by vanadium pentoxide. Invented in 1917 by H. D. Gibbs and C. Conover. 

Kawasaki Kasei A process for oxidizing naphthalene to naphthaquinone. It is operated in the gas phase at 400°C, using air as the oxidant, and uses vanadium pentoxide on silica as the catalyst. Phthalic acid is a co-product. 

A third option involves oxidizing naphthalene, possibly with vanadium pentoxide as a catalyst. 

Streptomyces griseus NRRL 8090 catalyzes a series of biotransformations of naphthalene and 2-methyl-1,4-naphthaquinone to their corresponding racemic and diastereomeric 4-hydroxy-1-tetralones (Figure 12.1). The yields of 4-hydroxy-l-tetralone obtained with S. griseus are much higher than those produced by various fungi that oxidize naphthalene. ... 

Biological. In activated sludge, 9.0% of the applied amount mineralized to carbon dioxide after 5 d (Freitag et al, 1985). Under certain conditions. Pseudomonas oxidized naphthalene to cis-1,2-dihydro-1,2-dihydroxynaphthalene (Dagley, 1972). This metabolite may be oxidized by Pseudomonasputida to carbon dioxide and water (Jerina et ah, 1971). Under aerobic conditions, Cunninghamella elegans degraded naphthalene to 1-naphthol, 2-naphthol, trans-l, 2-A hyAxoxy-... 

Cultures of Bacillus sp. oxidized naphthalene to (-r)-fran5-l,2-dihydro-l,2-dihydroxy-naphthalene. In the presence of reduced nicotinamide adeninedinucleotide phosphate (NADPH2) and ferrous ions, a cell extract oxidized naphthalene to fra/ 5-naphthalenediol (Gibson, 1968). Hydroxylation by pure microbial cultures yielded an unidentified phenol, 1- and 2-hydroxynaphthalene (Smith and Rosazza, 1974). 

Chemical/Physical. An aqueous solution containing chlorine dioxide in the dark for 3.5 d oxidized naphthalene to chloronaphthalene, 1,4-dichloronaphthalene, and methyl esters of phthalic acid (Taymaz et ah, 1979). In the presence of bromide ions and a chlorinating agent (sodium hypochlorite), major products identified at various reaction times and pHs include 1-bromonaphthalene, dibromonaphthalene, and 2-bromo-l,4-naphthoquinone. Minor products identified include chloronaphthalene, dibromonaphthalene, bromochloronaphthalene, bromo-naphthol, dibromonaphthol, 2-bromonaphthoquinone, dichloronaphthalene, and chlorodibromo-naphthalene (Lin et ah, 1984). 

An interesting biochemical method of manufacture is the utilization of bioengineered Pseudomonad plasmid (16) or Pseudomonas stut eri (17) in a culture medium to oxidize naphthalene or alkyl-substituted naphthalene. The metabolic oxidation products, unsubstituted or substituted salicylic acid,... 

Among the Ti02 powders, P25, which contains a 30% rutile phase and has a 43 m2/g surface area, showed the highest activity, as shown in Fig. 11.8. In this system, only three kinds of oxidized compounds (2-formylcinnamaldehyde and 1,3- and 1,4-dihydroxynaphthalene) among 10 possible isomers were obtained.81) Furthermore, no mono-hydroxylated compounds, i.e., 1- and 2-naphthol. were detected in the reaction products. Quantum efficiencies of the reactions were determined at around 365 nm. After photoirradiation for 1 h, the quantum efficiencies were determined to be 14.6% and 5.8% for the production of 2-formylcinnamaldehyde and 1,3-dihydroxynaphthalene, respectively. The efficiency was determined on the assumption that 4 holes are necessary to form one oxidized naphthalene molecule. 

The presence of water in the sol ution is essential to the production of oxidized naphthalene compounds. As shown in Fig. 11.9, the reaction rate increased with increase of water content and reached the maximum at a water content of about 6%. 

Comparison of the reactivities of benzene oxides, naphthalene oxides, phenanthrene oxides, and arene oxides derived from benzo [a] pyrene and 7,12-dimethylbenz[a] anthracene with hepatic glutathione S-epoxide transferase showed that benzene oxides without electron-withdrawing groups are poor substrates as also are polycyclic arene oxides. Only naphthalene oxide was a good substrate. 

Catalyst Special high-performance catalysts oxidize o-xylene as well as oxidizing naphthalene, o-xylene and mixtures of both feedstocks in any proportions. All catalysts are ring-shaped. 

The manufacture of phthalic anhydride (world installed capacity ca. 4.4 Mt/a) has several points of similarity to that of maleic anhydride in that there are two alternative feedstocks and a large amount of heat is released. The first process, introduced by BASF at the end of 19 century, was based on the liquid phase oxidation of naphthalene catalyzed by mercury salts. It was later replaced by the cleaner gas phase process, carried out over vanadium and molybdenum oxides. Naphthalene was supplied by coal tar distillation and was used exclusively until the end of 1950s when u-xylene, of petrochemical origin, became an abundantly available feedstock (Equation 36). A few production units however can use either feedstock, taking advantage of price fluctuations in coke plants (naphthalene) and in refineries (u-xylene). 

Similar tests of the fiuidized-bed method have been successful with a variety of molecular adsorbates and catalysts (other zeolites, supported oxides, naphthalene, pyridine, methanol, alkanes, alkenes, acetonitrile, ammonia, etc.) (25). We believe that this fiuidized-bed method is a major step forward for measurements of working catalysts with UV Raman spectroscopy. It should also be a useful method for measurements of catalytic kinetics by reducing heat and mass transfer effects that arise when catalysts are used in the form of pellets. In the limit of low conversions... 

Dimerization, oxidative Naphthalene-Lithium. Palladium acetate. Periodic acid. 

This result contrasts with the observations on anthracene sensitized photolysis, wherein no arylated diarylsulfides are observed. Naphthalene cation radical is sufficiently oxidizing (naphthalene Eox = 1.54 V versus SCE) to oxidize diphenylsulfide ( ox = 1.31 V versus SCE), whereas anthracene cation radical cannot (anthracene Eox = 1.09 V versus SCE) [94], Thus, diphenylsulfide cation radical/phenyl radical pair is formed by two sequential single electron transfer reactions in-cage, the subsequent chemistry being the same... 

PROBABLE FATE photolysis, relatively high solubility could make photooxidation an important fate, data inconclusive, atmospheric and photolytic half-life 71-550 days oxidation chlorine and/or ozone in sufficient quantities may oxidize naphthalene, photooxidation half-life in air 2.96-29.6 hrs hydrolysis not an important process volatilization could be very important but the rate is uncertain, half-life in water 25°C and 1 m depth 7.15 hr, based on an... 

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