Naphthalene 2-methylnaphthalene mixture

Gasoline contains more than 250 components of a mixture of C4-C12 hydrocarbons, which varies in concentration from batch to batch. Some of these components are isobutane, n-butane. isopentane, n-pentane, 2,3-dimethylbutane, 3-methylpentane, n-hexane, 2,4-dimethylpentane, benzene, 2-methylhexane, 3-meth-ylhexane, 2,2,4-trimethylpentane, 2,3,4-trimethylpentane, 2,5-dimethylhexane, 2,4-dimethylhexane, toluene, 2,3-dimethylhexane. ethylbenzene, methylethylbenzenes, m-, p-, and o-xylene, trimeth- ylbenzenes, naphthalene, methylnaphthalenes, and dimethylnaph-thalenes... 

CCRIS 7916 EINECS 215-329-7 HSDB 1143 Methyl naphthalene Methyl naphthalene (molten) Methylated naphthalenes Methyinaftalen Methyinaphthalene 2-Methylnaphthalene Methylnaphthalenes, liquid Methyl-naphthalenes, solid Methyinapthalene Naphthalene, methyl-. Mixture of a- and p-isomers. Has been used as an insecticide. Mixture of isomers of methyinaphthalene. 

Application of this technique to the identification of methyl esters of the organic acids obtained by the controlled oxidation of bituminous coal allowed the more volatile benzene carboxylic acid esters to be identified (Studier et al., 1978). These were esters of benzene tetracarboxylic acid, tere-phthalic acid, toluic acid, and benzoic acid. Decarboxylation of the total acid mixture was shown to afford benzene, toluene, Cj-benzenes (i.e., ethylbenzene or xylenes), Cj-benzenes, butylbenzenes, Cj-benzenes, Cybenzenes, naphthalene, methylnaphthalene, C2-naphthalene, biphenyl, methylbi-phenyl, C3-biphenyl, indane, methylindane, Cj-indane, phenanthrene, and fluorene. 

Dissolve 71 g. of P-methylnaphthalene in 460 g. (283 ml.) of A.B. carbon tetrachloride and place the solution in a 1 -litre three-necked flask equipped with a mechanical stirrer and reflux condenser. Introduce 89 g. of JV-bromosuccinimide through the third neck, close the latter with a stopper, and reflux the mixture with stirring for 16 hours. Filter ofiT the succinimide and remove the solvent under reduced pressure on a water bath. Dissolve the residual brown oil (largely 2-bromomethyl naphthalene) in 300 ml. of A.R. chloroform, and add it to a rapidly stirred solution of 84 g. of hexamine in 150 ml. of A.R. chloroform contained in a 2-litre three-necked flask, fitted with a reflux condenser, mechanical stirrer and dropping funnel maintain the rate of addition so that the mixture refluxes vigorously. A white solid separates almost immediately. Heat the mixture to reflux for 30 minutes, cool and filter. Wash the crystalline hexaminium bromide with two 100 ml. portions of light petroleum, b.p. 40-60°, and dry the yield of solid, m.p. 175-176°, is 147 g. Reflux the hexaminium salt for 2 hours with 760 ml. of 60 per cent, acetic acid, add 160 ml. of concentrated hydrochloric acid, continue the refluxing for 5 minutes more, and cool. Extract the aldehyde from the solution with ether, evaporate the ether, and recrystallise the residue from hot -hexane. The yield of p-naphthaldehyde, m.p. 69-60°, is 60 g. 

In additional experiments, HZSM-5 was precoked by converting methanol alone (into hydrocarbons) at 400 °C. Afterwards the zeolite was exposed to the 2-methylnaphtha-lene/methanol mixture, under the usual reaction conditions. The initial yield of 1-methylnaphthalene was significantly reduced (1.5 % compared to 4 % for the fresh catalyst, cf. Fig. 4). Furthermore, the initial content of 2,6- + 2,7-dimethylnaphthalene in the dimethyl-naphthalene fraction was 84 % instead of 70 % for the fresh catalyst. In another run, HZSM-5 was loaded with 0.5 wt.-% of Pt, and H2 was used as carrier gas instead of N2. Under these conditions, the formation of coke was avoided or at least drastically diminished. In-line with our model, no changes in the product yields and in the distribution of the dimethylnaphthalene isomers were observed with time on stream. 

Thiocyanation can be directed, by choice of suitable reaction conditions, to the nucleus or side chain of most aralkyl hydrocarbons. For example 1-methylnaphthalene gives exclusively l-methyI-4-cyanato-naphthalene in acetic acid in darkness but gives exclusively 1-thio-cyanatomethylnaphthalene on irradiated carbon tetrachloride solution. Mixtures of the two, in varying proportions, are obtained from solutions allowed to stand in ordinary sunlight. 

Figure 16.2. Some phase diagrams, (a) The water end of the system potassium chloride and water, (b) The water end of the system sodium chloride and water, (c) The water end of the system magnesium sulfate and water the heptahydrate goes to the mono at 150°C, and to anhydrous at 200°C. (d) /3-methylnaphthalene and /S-chloronaphthalene form solid solutions, (e) Mixtures of formamide and pyridine form a simple eutectic, (f) These mixtures form binary eutectics at the indicated temperatures and a ternary eutectic at mol fractions 0.392 dibenzyl, 0.338 diphenyl, and 0.27 naphthalene.

McCullough and co-workers first reported the photocycloaddition of acrylonitrile (33a) to naphthalene in 1970 [94,95], They systematically investigated the photocycloaddition of 33a to mono- and di-methylnaphthalenes however, the yields and selectivity were not high and usually a complex mixture was produced [128] (Scheme 18). 

Fig. 1 Gas chromatography-flame ionization detection chromatogram of a complex mixture of PAHs extracted by SFE from a contaminated soil. (1) naphthalene (2) 2-methylnaphthalene (3) 1-methylnaphthalene (4) acenaphthene (5) fluorene (6) dibenzothiophene (7) phenanthrene (8) anthracene (9) fluoranthene (10) pyrene (11) benzo(a)anthracene (12) chrysene (13) benzo(e)pyrene (14) benzo(a)pyrene (15) indeno(l,2,3-cd)pyrene (16) dibenzo(a,h)anthracene (17) benzo(g,h,i)perylene. (From Ref. [12].)...

Similar reaction of the adduct 5 with unsubstituted isobenzofuran was more involved. With lithium aluminum hydride, a 60% yield of a 1 3 mixture of 1//-cyclopropa[6]naphthalene (6) and 2-methyl- and 2-chloro-3-methylnaphthalenes (7) was obtained after 18 hours. The corresponding bromomethylnaphthalene 7 (X = Br) was also observed after a reaction time of only 2 hours. Use of butyllithium instead of lithium aluminum hydride improved the ratio of 6/7 to 3 1, while methyllithium gave a 60% yield of the cyclopropanaphthalene uncontaminated by methylnaphthalenes. ... 

A further method for the synthesis of naphthalene-2,6-dicarboxylic acid is based on 2-methylnaphthalene or mixtures of l-/2-methylnaphthalene. The methylnaph-thalenes are oxidized to carboxylic acids subsequent Henkel rearrangement, which was carried out a number of years ago on a large scale in Japan Teijin) at 400 to 500 °C under CO2 pressure of around 100 bar, converts the monocarboxylic acid to dicarboxylic acid. 

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