Aromatic compounds methylnaphthalene

Aromatic compounds are oxidized to quinones by bis(triorganosilyl) peroxides in the presence of a metal acid catalyst. Thus, 2-methylnaphthalene was oxidized with BTSP in the presence of Re207 and BU3PO in the presence of CHCI3, to a mixture of 59% 2-methyl-1,4-naphthoquinone and 8% 6-methy 1-1,4-naphthoquinone. ... 

Dimercury(I) n complexes are formed between aromatic compounds and Hg2(AsF6)2 in liquid S02 as solvent.113,121 Insoluble complexes with the ratio arene Hg2+ = 1 1 (arene = benzene, naphthalene, 2-methylnaphthalene, 2,6-dimethylnaphthalene, acenaphthene, fluor-anthrene, phenanthrene, anthracene, 9,10-dimethylanthracene or 1,3-dinitrobenzene) or 1 2 (arene = 9,10-benzophenanthrene) have been characterized by elemental analysis and, in some cases, by Raman spectrometry.113,120 The 13CNMR data allow the estimation of formation constants for the hexamethylbenzene, p-xylene and 1,4-dichlorobenzene complexes together with the chemical shifts for the bound substrates in these cases.121 Probably the coordination compounds of dimercury(I) salts with carbazole, dibenzofuran and diben-zothiophene are also n complexes.122... 

Figure 3.1 Acetylation at 373 K with acetic anhydride of a series of aromatic compounds over HBEA-15 zeolite. Conversion (XSUB) of anisole ( ), 2-methoxynaphthalene (x), m-xylene ( ), toluene ( ), 2-methylnaphthalene (o) and fluorobenzene (a) versus time. Reprinted from Journal of Catalysis, Vol. 230, Guidotti et al. Acetylation of aromatic compounds with H-BEA zeolite the influence of the substituents on the reactivity and on the catalyst stability, pp. 375-383, Copyright (2005), with permission from Elsevier...

Water-soluble cyclophanes QCP 44 or QCP 66 were impregnated as a carrier into the pores of membrane support. The SLMs showed isomer-selectivity for methylnaphthalenes (MNs), ethylnaphthalenes (ENs), dimethylnaphthalenes (DMNs), and three-ring aromatic compounds. The isomer selectivity of QCP 44 was completely opposite to that of QCP 66 the flux order of QCP 44 was 2-MN > 1-MN, 2-EN > 1-EN, 2,6-DMN > 1,5-DMN, and anthracene > phenanthrene and that of QCP 66 was 1-MN > 2-MN, 1-EN > 2-EN, 1,5-DMN and phenanthrene > anthracene. Cyclophanes exhibited facilitated transport for aromatic but not for... 

The particular value of the method is for converting methyl and polymethyl derivatives of polycyclic aromatic compounds into mono- and poly-carboxylic acids. For instance, 1-methylnaphthalene with a 42% excess of aqueous sodium dichromate solution in an autoclave at 240-250° gives 95% of 1-naphthoic acid in 18 h 2-methylnaphthalene with a 55% excess gives a 93% yield of 2-naphthoic acid the methyl group in fluoro-, bromo-, chloro-, nitro-, and methoxy-toluene as well as in xylenes and heterocycles can usually be oxidized smoothly to a carboxyl group. An excess of Na2Cr207 acts as a buffer and favors smooth reaction. With 1.5 moles of Na2Cr207 the reaction occurs in accord with the equation ... 

Fig. 10. GCMS total ion current (TIC) for aromatic hydrocarbon fractions are dominated by two and three ring aromatic compounds (a) Shublik A source rock extract (Prudhoe Bay Field) and (b) Kuparuk River Field oil-stained core, 3B-14 well, after long-term storage. Aromatic family labels are Nl, methylnaphthalenes N2, dimethylnaphthalenes D, dibenzothiophene Dl, methyldibenzothiophenes P, phenanthrene PI, methylphenanthrenes P2, dimethylphenanthrenes.

In fact, the El mass spectra in Figure 5.12 show that at 340°C xmsubstituted aromatic compounds (benzene, naphtiralene, anthracene) are present together with HCl, whereas at 450°C are mainly foimd alkyl aromatics (toluene, xylene, methylnaphthalene, and the like). ... 

The production of polysulfones was shown to be possible in Ref [ 181 ] by means of interaction of sulfuric acid, sulfur trioxide or their mixes with aromatic compounds (naphthalene, methylnaphthalene, methoxynaphtha-lene, dibenzyl ester, bisphenylcarbonate, bisphenyl, stilbene) if one used the anhydride of carbonic acid at 30-200 as the process activator. Obtained polymers could be reprocesses by means of pressing. 

Until recently, noncatalytic stoichiometric oxidations of arenes with toxic inorganic reagents, such as CrOj and K Cr O., MnO and KMnO, OsO, Pb(OAc), TllNOj), nitric acid, ceric ammonium nitrate, and some others, were the main route for the production of oxygenated aromatic compounds [1, 2, 6, 51]. A classic example is the manufacture ( 1500t/year) of vitamin via stoichiometric oxidation of 2-methylnaphthalene (MN) with carcinogenic CrO in sulfuric acid (Eq. 14.14) [52]. 

The process suffers from several drawbacks. For instance, the solvent must be able to dissolve both the apolar anthraquinone and the more polar hydroquinone and, at the same time, to provide immiscibility with water in order to allow the recovery of hydrogen peroxide. Complex mixtures of solvents are used, usually formed by an aromatic compound to dissolve the anthraquinone (toluene, methylnaphthalene) and a polar solvent to dissolve the hydroquinone (organic esters of phosphoric acid, diisobutylcarbinol, etc.). Even so, some derivatives of the quinone formed under the reaction conditions, particularly tetra- and octa-hydro derivatives are poorly soluble in the working solution. 

Machowska, Z., Mieluch, J., Obloj, J., et al (1987). Process for Preparing Vitamin K3 from 2-methylnaphthalene, Polish Patent PL 140780 Harrison, S., Fiset, G. and Mahdavi, B. (1999). Preparation of Quinones by Oxidation of Aromatic Compounds Using Electrochemically Prepared Ceric Ion, European Patent EP 919533. 

Figure 8 shows the preliminary results from our laboratory for selective adsorption of sulfur compounds from a commercial diesel fuel using a transition metal complex based adsorbent A-1. Figure 9 shows the corresponding results for a model diesel fuel that contains naphthalene, 2-methylnaphthalene, DBF and 4,6-DMDBT. Based on the computational and experimental results, it is theoretically possible and experimentally doable to distinguish between sulfur compounds and aromatic compounds in diesel fuels using a solid adsorbent. 

Solid-state irradiation of two component molecular crystals of thienylacetic acids with aza aromatic compounds (acridine and phenanthridine) ° results in photodecarboxylation and gives decarboxylated and condensation products. Two-component molecular crystals of the above azo aromatic compounds with 3-indolepropionic acid and 1-naphthylacetic acid, upon solid-state irradiation, give radical intermediates via electron transfer and ultimately afford decarboxylated compounds in near quantitative yield. Irradiation of crystalline charge-transfer complexes of 3-indoleacetic acid and 2-naphthylacetic acid with 1,2,4,5-tetracyanobenzene gives methylnaphthalene (decarboxylation) and naphthyl(2,4,5-tricy-ano)methane (dehydrocyanating condensation) in the solid state. 

Dehydrogenation (the conversion of alicycllc or hydroaromatic compounds into their aromatic counterparts by removal of hydrogen and also, in some cases, of other atoms or groups) finds wide application in the determination of structure of natural products of complex hydroaromatic structure. Dehydrogenation is employed also for the s)mthesis of polycyclic hydrocarbons and their derivatives from the readily accessible synthetic hydroaromatic compounds. A very simple example is the formation of p-methylnaphthalene from a-tetra-lone (which is itself prepared from benzene—see Section IV, 143) ... 

Fig. 5a-c. A typical distribution of polycyclic aromatic hydrocarbons in a atmospheric fallout sample, Alexandria City - Egypt b bottom incineration ash leachate of municipal solid waste - USA c hydrothermal petroleum, Escanaba Trough, NE Pacific Ocean. PAH Compound identifications N = naphthalene, MN = methylnaphthalene, DMN = dimethylnaphthalenes, P = phenanthrene, MP = methylphenanthrene, Fl = fluoranthene, Py = pyrene, BaAN = benzol anthracene, DH-Py = dihydropyrene, 2,3-BF = 2,3-benzofluorene, BFL = benzo[fc,/c]fluoranthene, BeP = benzo[e]pyrene, BaP = benzo[a]pyrene, Per = perylene, Cx-228 = methyl-228 series, Indeno = indeno[ l,2,3-c,d]pyrene, DBAN = dibenz[a,/z]anthracene, BPer = benzo[g,/z,z] perylene, AAN = anthanthrene, DBTH = dibenzothiophene, Cor = coronene, DBP = dibenzo [a,e]pyrene, DBPer = dibenzo [g,h,i] perylene... 

The fact that most alkylated benzenes show the same tendency to soot is also consistent with a mechanism that requires the presence of phenyl radicals, concentrations of acetylene that arise from the pyrolysis of the ring, and the formation of a fused-ring structure. As mentioned, acetylene is a major pyrolysis product of benzene and all alkylated aromatics. The observation that 1-methylnaphthalene is one of the most prolific sooting compounds is likely explained by the immediate presence of the naphthalene radical during pyrolysis (see Fig. 8.23). 

Polycyclic Aromatic Hydrocarbons, Two- or Three-Ring Compounds Acenaphthene Acenaphthylene Anthracene Methylnaphthalene Naphthalene Phenanthrene... 

The rate constant kTD for fluorescence of the pyrene intermolecular solution excimer has been found to follow the relation kFD = n2(kFD)n=I, where n is the the refractive index of the solvent69 . The values of kTO for the 1-methylnaphthalene excimer in ethanol at various temperatures are also consistent with the above relation 76). The fact that (kFD)n=I is independent of solvent and temperature indicates that the excimer has a specific structure, according to Birks 69,71). Experimentally, it was observed much earlier that kFM = n2(kFM)n=i for the polycyclic aromatic hydrocarbons, and that k /kp is independent of solvent and temperature. Table 5 shows that agreement between independent investigators of the excimers of naphthalene compounds is not always good, as in the case of 1-methylnaphthalene. 

Table XII presents compositional data for the aromatic hydrocarbons present in the anthracene oil. Compounds in the -12(H), -14(H), -18(H), and -22(H) series account for 78% of the aromatic hydrocarbons. The -12(H) compounds identified by GC/MS include naphthalene, 1- and 2-methylnaphthalene and at least 5 naphthalenes possessing 2 alkyl carbons. By GC/MS, acenaphthene and biphenyl account for 94% and 6%, respectively, of the first homolog in the -14(H) series. The parent member of the -18(H) series (C2.4H10 waS PreParat -ve -y isolated using GC and identified by UV and NMR to be >98% phenanthrene. The dominance of phenanthrene over anthracene in both high- and low- temperature coal tars has been previously noted (29,30,40,41,42,43). Thus, phenanthrene and presumably its alkylated homologs comprise the -18(H) Z series and account for 15.4% of the anthracene oil. The initial homolog in the -22(H) series, is comprised of 58%...

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