2.3- Dimethylbutanal

Because of isomerization, alkylation of benzene with tertiary alkyl haUdes can also yield secondary alkylbenzenes rather than only tertiary alkylbenzenes (20). For example, the / fAhexylbenzene, which is first formed by the reaction of benzene with 2-chloro-2,3-dimethylbutane and AlCl isomerizes largely to 2,2-dimethyl-3-phenylbutane by a 1,2-CH2 shift. With ferric chloride as the catalyst, / fAhexylbenzene does not undergo isomerization and is isolated as such. 

Cycloaliphatics. Synthesized cycloahphatics are generally not utilized as hydrauhc fluids. Cycloahphatics are synthesized for use as traction lubricants because, under high stress, they have high traction coefficients and excellent stabihty. A typical cycloahphatic used as a synthetic traction fluid is 2,3-dicydohexyl-2,3-dimethylbutane [5171 -88-0] ... 

Hexane refers to the straight-chain hydrocarbon, C H branched hydrocarbons of the same formula are isohexanes. Hexanes include the branched compounds, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, 2,3-dimethylbutane, and the straight-chain compound, / -hexane. Commercial hexane is a narrow-boiling mixture of these compounds with methylcyclopentane, cyclohexane, and benzene (qv) minor amounts of and hydrocarbons also may be present. Hydrocarbons in commercial hexane are found chiefly in straight-mn gasoline which is produced from cmde oil and natural gas Hquids (see Gasoline AND OTHER MOTOR fuels Gas,natural). Smaller volumes occur in certain petroleum refinery streams. 

The rates of these two reactions have been studied for the attack of trifluoromethyl (51) and methyl radicals (52) in isoprene that has been dissolved in 2,3-dimethylbutane and isooctane, respectively. The rate constants for the reactions with isoprene are much greater than those for the attack on the solvent. The ratio between the two rates for the attack of trifluoromethyl radicals varies from 1090 at 65°C to 233 at 180°C. For the corresponding reaction involving methyl radicals, the ratio is 2090 at 65°C. 

Dimethyl- Propene Ethane, ethylene, propane, 1- butene, 2,3-dimethylbutane, 2- methyl-4-pentene, isobutane, 1,5-hexadiene... 

Nordihydroguaiaretic [l,4Tbis(3,4-dihydroxyphenyl)-2,3-dimethylbutane] acid [500-38-9] M 302.4, m 184-185", pKEst(i) 9.7, pKEst(2) 12. Crystd from dilute acetic acid. 

Using the data incorporated in Fig. 3.3 and assuming the additivity of gauche and eclipsing interactions of similar type, sketch the rotational energy profile you would expect for 2,3-dimethylbutane. 

Important differences are seen when the reactions of the other halogens are compared to bromination. In the case of chlorination, although the same chain mechanism is operative as for bromination, there is a key difference in the greatly diminished selectivity of the chlorination. For example, the pri sec selectivity in 2,3-dimethylbutane for chlorination is 1 3.6 in typical solvents. Because of the greater reactivity of the chlorine atom, abstractions of primary, secondary, and tertiary hydrogens are all exothermic. As a result of this exothermicity, the stability of the product radical has less influence on the activation energy. In terms of Hammond s postulate (Section 4.4.2), the transition state would be expected to be more reactant-like. As an example of the low selectivity, ethylbenzene is chlorinated at both the methyl and the methylene positions, despite the much greater stability of the benzyl radical ... 

Dimethylbutane, 56 Dimethyl carbamoyl chloride, 56 Dimethyldichlorosilane, 56 Dimethyldiethoxysilane, 56 Dimethyldisulfide, 56... 

Volume of olefin/(volume of ionic liquid.hour). i-C = 2,2- and 2,3-dimethylbutanes, i-Cg = isooctanes, TMP trimethylpentanes, = hydrocarbon products with more than eight carbon atoms, Light ends = hydrocarbon products with fewer than eight carbon atoms, RON = research octane number, MON = motor octane number... 

I Sight along the C2-C3 bond of 2,3-dimethylbutane, and draw a Newman projection of the most stable conformation. 

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