Methyl naphthalene oxidation

CASRN 90-12-0 molecular formula CnHio FW 142.20 ChemicaPPhysical. An aqueous solution containing chlorine dioxide in the dark for 3.5 d at room temperature oxidized 1-methylnaphthalene into the following 2-chloro-l-methyl-naphthalene, 4-chloro-1-methylnaphthalene, 2,4-dichloro-1-methylnaphthalene, 1-hydroxymethyl-naphthalene, 1-naphthaldehyde, and 1-naphthoic acid (Taymaz et al., 1979). 

Aromatic hydrocarbons which have methyl side chains mainly behave like toluene and form aldehydes, while combustion is stimulated and selective oxidation of the nucleus is repressed. The oxidation of methyl-naphthalene, for example, exhibits a low selectivity with respect to phtha-lic anhydride formation, combustion and maleic acid formation being the dominating reactions. Durene is a special case because it resembles o-xy-lene. The oxidation of durene over a V—W—O catalyst at 420° C is reported to produce pyromellitic dianhydride, phthalic and maleic anhydride, although combustion dominates (Geiman et al. [122]). 1,2,4-Trimethyl-benzene yields dimethylbenzene and trimellitic acid if oxidized on a Sn— V—O catalyst. Kinetic data have been measured by Balsubramanian and Viswanath [37]. 

Tar Fluorene Diphenylene oxide Acenaphthene Methyl-naphthalenes... 

Amoco Amoco Chemicals Company, a subsidiary of Amoco Corporation, formerly Standard Oil Company (IN), is best known in the chemicals industry for its modification of the Mid-Century process for making pure terephthalic acid. p-Xylene in acetic acid solution is oxidized with air at high temperature and pressure. Small amounts of manganese, cobalt, and bromide are used as catalysts. The modification allows the use of terephthalic acid, rather than dimethyl terephthalate, for making fiber. The process can also be used for oxidizing other methylbenzenes and methyl-naphthalenes to aromatic carboxylic acids. See also Maruzen. 

A second class of oxidation in which these systems have been applied is conversion of electron-rich arenes to quinones.50 Oxidation of 2-methyl-naphthalene showed a significant selectivity for formation of 2-methylnaph-thoquinone over the 6-methyl isomer. This was later proposed33 to proceed via epoxidation of the electron-rich arene ring, followed by ring opening and further oxidation of the hydroquinone. 

Fig. 8. Aromatic ring systems in Murchison polymer (Hayatsu et al., 1977, 1980a). Gentle oxidation converts substituents to COOH groups, but leaves ring systems intact. In addition to the ring systems shown, methyl naphthalene and methyl phenanthrene were also identified (Hayatsu et al., 1980a)...

The alkyl naphthalenes, such as methyl naphthalene, may be oxidized to phthalic anhydride in the same manner as naphthalene, thus making it possible to use cruder grades of naphthalene. Thus, crude naphthalene obtained by centrifuging the oils from the proper cut from the distillation of coal-tar (whizzed naphthalene) consisting principally of naphthalene to the extent of 50 to 80 per cent and usually containing considerable quantities of alkyl naphthalenes and other ring compounds may be treated in a manner similar to that used in the oxidation of pure naphthalene. The reaction products contain phthalic anhydride, benzoic acid, naphthoic acids and anhydrides, etc.81... 

FIGURE 5.10 Oxidation stability of white oil formulations with added P-methyl naphthalene and t-dodecyl mercaptan. 

Oxidation of 2-methyl naphthalene Metal salt and heteropolyacid 2-Methyl 1.4 naphthoquinone Kozhevnikov (1995)... 

Fig. 6 Proposed catalytic oxidation cycle for conver.sion of napthalene-2-carbaldehyde to methyl naphthalene-2-carboxylate using a...

Benzene Toluene Xylene Tar acids Tar bases Solvent Naphtha Tar acids Tar bases Naphthalene Methyl-naphthalene Acenapthene Fluorene Diphenylene oxide Phenathracene Anthracene Carbazole Chrysene Fluoranthene Pyrene... 

Mochida (58) developed a process in which a synthetic mesophase is produced from the HF/BF3 catalyzed polymerization of naphthalene or methyl naphthalene. HF/BF3 is a Bronsted acid that has been used to catalyze coal liquifaction and aromatic condensation. The aromatic resin (AR)-mesophase produced through this process is both more spinnable and more easily oxidized than that produced from... 

Methyl- and dimethylnaphthalenes are contained in coke-oven tar and in certain petroleum fractions in significant amounts. A typical high temperature coke-oven coal tar, for example, contains ca 3 wt % of combined methyl- and dimethylnaphthalenes (6). In the United States, separation of individual isomers is seldom attempted instead a methylnaphtha1 ene-rich fraction is produced for commercial purposes. Such mixtures are used for solvents for pesticides, sulfur, and various aromatic compounds. They also can be used as low freezing, stable heat-transfer fluids. Mixtures that are rich in monomethyinaphthalene content have been used as dye carriers (qv) for color intensification in the dyeing of synthetic fibers, eg, polyester. They also are used as the feedstock to make naphthalene in dealkylation processes. PhthaUc anhydride also can be made from m ethyl n aph th al en e mixtures by an oxidation process that is similar to that used for naphthalene. 

Naphthalenedicarboxylic acid has been prepared by fusing dipotassium 2,6-naphthalenedisulfonate with potassium cyanide to give the corresponding dinitrile, which is hydrolyzed by oxidation of 2-methyl-6-acetylnaphthalene with dilute nitric acid at 200 by the thermal disproportionation of potassium a- or /3-naphthoate to dipotassium 2,6-naphthalenedicarboxylate and naphthalene and by the present method. The present method is much more convenient than earlier methods, if a suitable autoclave is available. 

The presence of free bromine, and consequently the end-point, can be detected by its yellow colour, but it is better to use indicators such as methyl orange, methyl red, naphthalene black 12B, xylidine ponceau, and fuchsine. These indicators have their usual colour in acid solution, but are destroyed by the first excess of bromine. With all irreversible oxidation indicators the destruction of the indicator is often premature to a slight extent a little additional indicator is usually required near the end point. The quantity of bromate solution consumed by the indicator is exceedingly small, and the blank can be neglected for 0.02M solutions. Direct titrations with bromate solution in the presence of irreversible dyestuff indicators are usually made in hydrochloric acid solution, the concentration of which should be at least 1.5-2M. At the end of the titration some chlorine may appear by virtue of the reaction ... 

Naphthalene dioxygenase from P. putida strain FI is able to oxidize a number of haloge-nated ethenes, propenes, and butenes, and d5 -hept-2-ene and cis-oct-2-ene (Lange and Wackett 1997). Alkenes with halogen and methyl substituents at double bonds form allyl alcohols, whereas those with only alkyl or chloromethyl groups form diols. 

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