Of isopropylbenzene

The formation of isopropylbenzene when n-propyl chloride is employed as the alkylating agent is readily accounted for by the isomerisation of the alkyl carbonium (or alkylium) ion ... 

Give the structure of the expected product from the reaction of isopropylbenzene with... 

The best preparative results from autoxidation are encountered when only one relatively reactive hydrogen is available for abstraction. The oxidation of isopropylbenzene (cumene) is carried out on an industrial scale, with the ultimate products being acetone and phenol ... 

Ptlugmacher U, B Averhoff, G Gottschalk (1996) Cloning, sequencing, and expression of isopropylbenzene degradation genes from Pseudomonas sp, strain JRl identification of isopropylbenzene dioxygenase that mediates trichloroethene oxidation. Appl Environ Microbiol 62 3967-3977. 

Aluminum Trichloride. In an analogous way, an AICI3 containing waste of isopropylbenzene production [189] can be used as an acid hardener for urea-formaldehyde resins. The waste from the production of isopropylbenzene (via a Friedel-Crafts reaction) contains approximately 200 to 300 g/liter of AICI3. 

V. A. Blazhevich, D. A. Khisaeva, V. G. Umetbaev, and I. V. Legostaeva. Polymer plugging solution for oil and gas wells—contains urea-formaldehyde resin, and aluminium chloride containing waste of isopropylbenzene production as acid hardener. Patent SU 1763638-A, 1992. 

TABLE 3.1.1.11.1 Reported aqueous solubilities and Henry s law constants of isopropylbenzene at various temperatures Aqueous solubility Henry s law constant ... 

Photolytic. Major products reported from the photooxidation of isopropylbenzene with nitrogen oxides include nitric acid and lienzaldehyde (Altshuller, 1983). A / -hexane solution containing isopropylbenzene and spread as a thin film (4 mm) on cold water (10 °C) was irradiated by a mercury medium pressure lamp. In 3 h, 22% of the applied isopropylbenzene photooxidized into a,a-dimethylbenzyl alcohol, 2-phenylpropionaldehyde, and allylbenzene (Moza and Feicht, 1989). 

A rate constant of 3.7 x 10 L/molecule-sec was reported for the reaction of isopropylbenzene with OH radicals in the gas phase (Darnall et al., 1976). Similarly, a room temperature rate constant of 6.6 x lO cmVmolecule-sec was reported for the vapor-phase reaction of isopropylbenzene with OH radicals (Atkinson, 1985). At 25 °C, a rate constant of 6.25 x 10 cmVmolecule sec was reported for the same reaction (Ohta and Ohyama, 1985). 

The calculated evaporation half-life of isopropylbenzene from surface water 1 m deep at 25 °C is 5.79 h (Mackay and Leinonen, 1975). 

Jigami, Y., Omori, T., and Minoda, Y. The degradation of isopropylbenzene and isobutylbenzene by Pseudomonassp., Agric. Biol Chem., 39(9) 1781-1788, 1975. 

Let us assume that the 2- and 3-dephenylation reactions to form the parent heterocycle isoxazolidine have the same enthalpies as those of isopropylbenzene and dimethylani-line, 108.7 and 118.6 kJmol , respectively. Therefore, the enthalpy of formation of isoxazolidine is predicted to be ca 6 kJmoL. Consider the reaction in eqnation 13. 

Production of phenol and acetone is based on liquid-phase oxidation of isopropylbenzene. Synthetic fatty acids and fatty alcohols for producing surfactants, terephthalic, adipic, and acetic acids used in producing synthetic and artificial fibers, a variety of solvents for the petroleum and coatings industries—these and other important products are obtained by liquid-phase oxidation of organic compounds. Oxidation processes comprise many parallel and sequential macroscopic and unit (or very simple) stages. The active centers in oxidative chain reactions are various free radicals, differing in structure and in reactivity, so that the nomenclature of these labile particles is constantly changing as oxidation processes are clarified by the appearance in the reaction zone of products which are also involved in the complex mechanism of these chemical conversions. 

Friedel-Crafts reaction of isopropylbenzene and 2-methylpropenal diacetate (methacrolein diacetate) in the presence of titanium tetrachloride/boron trifluoride etherate gives cyclamenaldehyde enolacetate, which is hydrolyzed to the aldehyde [151] ... 

Gao et al. (346) obtained SER spectra of toluene, isopropylbenzene, and ferf-butylbcnzene on roughened gold electrodes. The spectra are reasonably interpreted in terms of flat-lying molecules, 77-bonded to the surface via the aromatic ring. However, one imagines that the 77-bonding must be weaker in the presence of the bulky ferf-butyl substituent, and for this molecule all the bands in the spectrum of the liquid occur also in the SER spectrum. (The normal Raman spectrum shown in Fig. 2A of the Gao et al. paper (346) is that of isopropylbenzene rather than that of the indicated toluene.)... 

Side-Chain Isomerization. Arylalkanes undergo acid-catalyzed isomerization in the side chain in a way similar to the skeletal rearrangement of alkanes.70-72 There are, however, notable differences. Propylbenzene, for instance, yields only a small amount (a few percentages) of isopropylbenzene 73 Similarly, sec-butyl- and iso-butylbenzene are interconverted at 100°C with wet A1C13, but only a negligible amount of tert-butylbenzene is formed.74 In the transformation of labeled propylbenzene the recovered starting material was shown to have equal amounts of labeling in the a and p positions of the side chain, but none in the y position 73... 

These experimental observations were explained by invoking the formation of the most stable benzylic carbocation that then undergoes rearrangement via an intermediate phenonium ion72 (Scheme 4.5). This mechanism accounts for cc-p isotope scrambling, and the low amount of isopropylbenzene is in harmony with the involvement of the primary cation. Other observations, in turn, suggest the involvement of the n complex of the arene and the side-chain carbocation.73-75... 

It follows from all the above considerations that the acidic character of the surface is necessary for the esterification reaction. This view is supported by the parallel found by some workers [405,406] between the rate of esterification and that of other typical acid-catalysed reactions. A linear correlation was established between the rate of acetic acid—ethanol esterification and that of deisopropylation of isopropylbenzene on a series of silica—alumina, alumina—boria and alumina catalysts [406] a similar relation was found between the rate coefficient of the same esterification reaction and the cracking activity of a series of silica—alumina catalysts prepared in a different way [405]. 

Unlike alkylation, acylation is controlled easily to give monosubstitution, because once an acyl group is attached to a benzene ring, it is not possible to introduce a second acyl group into the same ring. Because of this, a convenient synthesis of alkylbenzenes starts with acylation, followed by reduction of the carbonyl group with zinc and hydrochloric acid (Section 16-6). For example, propylbenzene is prepared best by this two-step route because, as we have noted, the direct alkylation of benzene with propyl chloride produces considerable amounts of isopropylbenzene and polysubstitution products ... 

Current commercial syntheses of benzenol involve oxidation of methyl-benzene or isopropylbenzene (Section 16-9E). Oxidation of isopropylbenzene is economically feasible for the production of benzenol because 2-propanone... 

As Margerison and Nyss noted 289) this reaction path is similar to one given by Benkeser et al.290) to explain the formation of l,l,3-trimethyl-3-phenylindane in the course of the metallation of isopropylbenzene by w-pentylsodium ... 

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