Butylate Butylbenzene

The fact that n-butylbenzene can be prepared in reasonable yield by the action of sodium upon a mixture of bromohenzene and n-butyl bromide can be partly explained on the assumption that n-butyl bromide reacts with phenyl-sodium more rapidly than does bromobenzene. It is interesting to note that n-butylbenzene can be prepared either from benzylsodium and n-propyl bromide or from phenylsodium and n-butyl bromide (Section VI,29). 

Kinetic data are available for the nitration of a series of p-alkylphenyl trimethylammonium ions over a range of acidities in sulphuric acid. - The following table shows how p-methyl and p-tert-h xty augment the reactivity of the position ortho to them. Comparison with table 9.1 shows how very much more powerfully both the methyl and the tert-butyl group assist substitution into these strongly deactivated cations than they do at the o-positions in toluene and ferf-butylbenzene. Analysis of these results, and comparison with those for chlorination and bromination, shows that even in these highly deactivated cations, as in the nitration of alkylbenzenes ( 9.1.1), the alkyl groups still release electrons in the inductive order. In view of the comparisons just... 

Figure 12 7 illustrates attack on the benzene ring by tert butyl cation (step 1) and subsequent formation of tert butylbenzene by loss of a proton from the cyclohexadienyl cation intermediate (step 2)... 

Some degree of regioselectivity can be imposed on l//-azepine formation if the arene has substituents of high steric demand.63 For example, the thermolysis of ethyl azidoformate in a tenfold molar excess of 1,4-di-fert-butylbenzene yields a 95 5 mixture of the di-zerr-butyl-l//-azcpincs 3 and 4, crystallization of which yields the pure 3,6-di-/er/-butyl isomer 3. 

The products from the thermolyses of other alkyl and aryl azidoformates in 1,4-di-tm-butylbenzene are unpredictable. In some cases, e.g. with cyclopropylmethyl, tert-butyl and 4-methoxyphenyl azidoformates, only the corresponding 3,6-di-/< rt-butyl-l//-azepines are... 

A kinetic isotope effect, kH/kD = 1.4, has been observed in the bromination of 3-bromo-l,2,4,5-tetramethylbenzene and its 6-deuterated isomer by bromine in nitromethane at 30 °C, and this has been attributed to steric hindrance to the electrophile causing kLx to become significant relative to k 2 (see p. 8)268. A more extensive subsequent investigation304 of the isotope effects obtained for reaction in acetic acid and in nitromethane (in parentheses) revealed the following values mesitylene, 1.1 pentamethylbenzene 1.2 3-methoxy-1,2,4,5-tetramethyl-benzene 1.5 5-t-butyl-1,2,3-trimethylbenzene 1.6 (2.7) 3-bromo-1,2,4,5-tetra-methylbenzene 1.4 and for 1,3,5-tri-f-butylbenzene in acetic acid-dioxan, with silver ion catalyst, kH/kD = 3.6. All of these isotope effects are obtained with hindered compounds, and the larger the steric hindrance, the greater the isotope... 

Subsequently, rate coefficients were determined for the zinc chloride-catalysed bromination of benzene, toluene, i-propyl-benzene, r-butylbenzene, xylenes, p-di-f-butylbenzene, mesitylene, 1,2,4-trimethyl-, sym-triethyl-, sym-tri-f-butyl-, 1,2,3,5-and 1,2,4,5-tetramethyl- and pentamethylbenzenes, all at 25.4 °C and in acetic acid, and it was shown that the reaction was inhibited by HBr.ZnCl2 which accumulates during the bromination and was considered to cause the first step of the reaction (formation of ArHBr2) to reverse320. The second-order coefficients for bromination of o-xylene at 25.0 °C were shown to be inversely dependent upon the hydrogen bromide concentration and the reversal of equilibrium (155)... 

Although there are a number of reports in the literature of this process, (see ref. 1) only one of these relates to a kinetic study of the reaction168. The ease with which the reaction takes place depends upon the stability of the leaving carbonium ion. Consequently, de-r-butylation is mcst frequently observed and in a kinetic study of the sulphonation of /-butylbenzene in aqueous sulphuric acid (see p. 72) this side reaction was sufficiently prominent for rates to be easily measurable (Table 225)168. Comparison of the rates with those in Table 42 shows that de-... 

Butane, 1,4-diiodo-, 30, 33 2-Butanone, 3-acetamido-, 33,1 n-BuTYLACETYLENE, 30, IS tert-Butyl alcohol, 30, 19, 20 32, 20 ierl-Butylbenzene, 32, 91 n-Butyl bromide, 30, 16 tert-Butyl hypochlorite, 32, 20 n-Butyl iodide, 30, 34 Butylketene dimer, 31, 71 -ter -Butylphenyl salicylate, 32, 26 Butyrchloral, 33, IS Butyric acid, a, y-dicyano-o-phenyl-, ethyl ester, 30, 80... 

Dichloromethane solutions of some sterically congested benzyl chlorides and triethylsilane need only the addition of excess trifluoroacetic acid to promote rapid conversion of the chlorides to the related hydrocarbons.128 Thus 2,4,6-trimethylbenzyl chloride produces a 79% yield of isodurene at room temperature after 2.5 hours, 2-methyl-4,6-di-/m-bu(ylbenzyl chloride gives 50% 1, 2-di-methyl-4,6-di-tm-butylbenzene after 40 minutes at reflux, and 2,4,6-tm-butyl-benzyl chloride gives a 100% yield of 2,4,6-tri-rm-butyltoluene within 17 minutes at reflux (Eq. 54). The unsubstituted parent benzyl chloride remains unreacted under these conditions even after 30 days.128... 

Butylated hydroxytoluene (BHT), 12 60 antioxidant useful in cosmetics, 7 830t as soap bar additive, 22 744-745 4- -Butylbenzaldehyde, 9 680-681 ft-Butylbenzene, 12 163 IV-Butylbenzenesulfonamide, 2 550t Butyl benzoate, 3 635... 

Ogimachi et al. (1955) also investigated in more detail the steric effect on the equilibrium constants of the complex formation of ICl with various benzene derivatives. The basicity decreases greatly on substitution of bulky groups, e.g. the t-butyl group. This effect is particularly pronounced for 1,3,5-tri-t-butylbenzene. 

Synonyms AI3-00119 1-BB j-BB BRN 1903395 Butylbenzene 1-Butylbenzene /j-Butyl-benzene /j-BuBz EINECS 203-209-7 NSC 8465 1-Phenylbutane l-Phenyl- 3-butane UN 2709. 

AI3-00040, see Cyclohexanol AI3-00041, see Cyclohexanone AI3-00045, see Diacetone alcohol AI3-00046, see Isophorone AI3-00050, see 1,4-Dichlorobenzene AI3-00052, see Trichloroethylene AI3-00053, see 1,2-Dichlorobenzene AI3-00054, see Acrylonitrile AI3-00072, see Hydroquinone AI3-00075, see p-Chloro-rrr-cresol AI3-00078, see 2,4-Dichlorophenol AI3-00085, see 1-Naphthylamine AI3-00100, see Nitroethane AI3-00105, see Anthracene AI3-00109, see 2-Nitropropane AI3-00111, see Nitromethane AI3-00118, see ferf-Butylbenzene AI3-00119, see Butylbenzene AI3-00121, see sec-Butylbenzene AI3-00124, see 4-Aminobiphenyl AI3-00128, see Acenaphthene AI3-00134, see Pentachlorophenol AI3-00137, see 2-Methylphenol AI3-00140, see Benzidine AI3-00142, see 2,4,6-Trichlorophenol AI3-00150, see 4-Methylphenol AI3-00154, see 4,6-Dinitro-o-cresol AI3-00262, see Dimethyl phthalate AI3-00278, see Naphthalene AI3-00283, see Di-rj-butyl phthalate AI3-00327, see Acetonitrile AI3-00329, see Diethyl phthalate AI3-00399, see Tributyl phosphate AI3-00404, see Ethyl acetate AI3-00405, see 1-Butanol AI3-00406, see Butyl acetate AI3-00407, see Ethyl formate AI3-00408, see Methyl formate AI3-00409, see Methanol AI3-00520, see Tri-ocresyl phosphate AI3-00576, see Isoamyl acetate AI3-00633, see Hexachloroethane AI3-00635, see 4-Nitrobiphenyl AI3-00698, see IV-Nitrosodiphenylamine AI3-00710, see p-Phenylenediamine AI3-00749, see Phenyl ether AI3-00790, see Phenanthrene AI3-00808, see Benzene AI3-00867, see Chrysene AI3-00987, see Thiram AI3-01021, see 4-Chlorophenyl phenyl ether AI3-01055, see 1.4-Dioxane AI3-01171, see Furfuryl alcohol AI3-01229, see 4-Methyl-2-pentanone AI3-01230, see 2-Heptanone AI3-01231, see Morpholine AI3-01236, see 2-Ethoxyethanol AI3-01238, see Acetone AI3-01239, see Nitrobenzene AI3-01240, see I idine AI3-01256, see Decahydronaphthalene AI3-01288, see ferf-Butyl alcohol AI3-01445, see Bis(2-chloroethoxy)methane AI3-01501, see 2,4-Toluene diisocyanate AI3-01506, see p,p -DDT AI3-01535, see 2,4-Dinitrophenol AI3-01537, see 2-Chloronaphthalene... 

BuAc, see sec-Butyl acetate sec-BuAc, see sec-Butyl acetate f-BuAc, see fert-Butyl acetate i-BuBz, see Isobutylbenzene n-BuBz, see Butylbenzene sec-BuBz, see sec-Butylbenzene f-BuBz, see fert-Butylbenzene fert-BuBz, see fert-Butylbenzene BUGS, see 2-Butoxyethanol Bug master, see Carbaryl Bunt-cure, see Hexachlorobenzene Bunt-no-more, see Hexachlorobenzene 1-BuOH, see 1-Butanol... 

Butylbenzene, see Butylbenzene f -Butylbenzene, see Isobutylbenzene n-Butylbenzene, see Butylbenzene s-Butylbenzene, see sec-Butylbenzene secondar/-Butylbenzene, see sec-Butylbenzene f-Butylbenzene, see ferf-Butylbenzene ferffar/ Butylbenzene, see ferf-Butylbenzene Butyl benzyl phthalate, see Benzyl butyl phthalate n-Butyl benzyl phthalate, see Benzyl butyl phthalate Butyl cellosolve, see 2-Butoxyethanol n-Butyl cellosolve, see 2-Butoxyethanol Butylene, see 1-Butene 1-Butylene, see 1-Butene... 

Pseudobutylbenzene, see fert-Butylbenzene Pseudocumene, see 1,2,4-Trimethylbenzene Pseudocumol, see 1,2,4-Trimethylbenzene Puralin, see Thiram PX 104, see Di-n-butyl phthalate PX 138, see Di-n-octyl phthalate Pyranton, see Diacetone alcohol Pyranton A, see Diacetone alcohol p-Pyrene, see Pyrene... 

Butylated hydroxytoluene, see Ethyl ether Butylate sulfoxide, see Butvlate Butylbenzene, see Isobutylbenzene, PCB-1242... 

Steele, W.V., Chirico, R.D., Knipmeyer, S.E., and Nguyen, A. Vapor pressure, heat capacity, and density along the saturation line measurements for benzenamine,butylbenzene, sec-butylbenzene, ferf-butylbenzene, 2,2-dimethylbutanoic acid, trideca-fluoroheptanoic acid, 2-butyl-2-ethyl-l, 3-propanediol, 2,2,4-trimethyl-l, 3-pentanediol, and l-chloro-2-propanol, J. Chem. Eng. Data, 47(4) 648-666, 2002a. 

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