Cyclohexene reaction with benzene

Tphe rate-limiting processes in catalytic reaction over zeolites remain A largely undefined, mainly because of the lack of information on counterdiffusion rates at reaction conditions. Thomas and Barmby (7), Chen et al. (2, 3), and Nace (4) speculate on possible diffusional limitations in catalytic cracking over zeolites, and Katzer (5) has shown that intracrystalline diffusional limitations do not exist in liquid-phase benzene alkylation with propene. Tan and Fuller (6) propose internal mass transfer limitations and rapid fouling in benzene alkylation with cyclohexene over Y zeolite, based on the occurrence of a maximum in the reaction rate at about 100 min in flow reaction studies. Venuto et al (7, 8, 9) report similar rate maxima for vapor- and liquid-phase alkylation of benzene and dehydro-... 

Phenyliodonium bis(perfluoroalkanesulfonyl)methide 200 can react with various organic substrates upon irradiation with UV light [141,142]. For example, the reaction with cyclohexene affords cycloaddition product 201, while the photolysis of 200 in benzene or toluene leads to the C-H insertion products 202 (Scheme 72) [142]. 

This is a mild brominating agent. In benzene solution in the presence of dibenzoyl peroxide, hydrocarbons such as toluene undergo benzylic bromination. In acetic acid solution aromatic substitution is observed. In the reaction with cyclohexene the only product obtained was that of addition (1,2-dibromocyclohexane, 80%) regardless of the solvent and in the presence or absence of dibenzoyl peroxide. F. D. Chattaway and G. Hoyle, J. Chem.Soc., 123,654 (1923)... 

The mechanism of the reaction is unknown. The stereospecificity observed with (E)- and (Z)-l-methyl-2-phenylethylene points to a one-step reaction. The very low Hammett constant, -0.43, determined with phenylethylenes substituted in the benzene ring, excludes polar intermediates. Yields of only a few percent are obtained in the reaction of aliphatic alkenes with (52). In the reaction of cyclohexene with (52), further amination of the aziridine to aminoaziridine (99) is observed. Instead of diphenylazirine, diphenylacetonitrile (100) is formed from diphenylacetylene by NH uptake from (52) and phenyl migration. 

Reaction with Acrylonitrile (9) As in the preceding case, a mixture of 61 g (0.45 mole) of aluminum chloride in 300 ml of benzene is heated to 60°, and a solution of 26.6 g (0.5 mole) of acrylonitrile in 100 ml of benzene is added. Butadiene (0.9 mole) is bubbled into the stirred and heated solution over a period of 4 hours, and the reaction mixture is worked up as above. Distillation gives 3-cyclohexene-1-carbonitrile, bp 80-87°/20 mm, nj,° 1.4742, in about 85% yield. 

Methyl phenyl sulfide, see Thioanisole Methyl phenyl sulfoxide, 46, 78 from methylsulfinyl chloride and benzene with anhydrous alumi num chloride, 46, 80 Methyl vinyl ketone, reaction with 1-morpholino 1 cyclohexene, 45,... 

FIRST-ORDER RATE COEFFICIENTS FOR REACTION OF CYCLOHEXENE WITH BENZENE... 

The first reactions concerned (Simons and Archer, 27) alkylation of benzene with propylene to form isopropylbenzene, with isobutene to form f-butylbenzene and di-f-butylbenzene, and trimethylethylene to form amylbenzene. Later on (Simons and Archer, 28) studied these and other reactions in more detail and showed that high yields could be obtained and that the product was not contaminated with tars or other obnoxious impurities. It was shown that the products obtained with trimethylethylene were mono- and di-f-amylbenzene, that phenyl-pentane resulted from the use of pentene-2, and that cyclohexene produced cyclohexylbenzene. Cinnamic acid reacted with benzene (Simons and Archer, 29) to form /3-phenylpropionic acid and allyl benzene reacted with benzene to form 1,2-diphenylpropane. It is interesting to note that although allyl alcohol reacted with benzene to form 1,2-diphenylpropane, the intermediate in the reaction, allylbenzene, was isolated and identified. This shows that in this case the hydroxyl reacted at a more rapid rate than the double bond. Both di- and triisobutylene reacted with phenol (Simons and Archer, 30) at 0°, when using hydrogen fluoride containing only relatively small quantities of water, to form f-butyl-benzene, but diisobutylene with 70% hydrogen fluoride produced p-f-octylphenol. Cyclohexene reacted with toluene to form cyclohexyl-toluene and octene-1 rapidly reacted with toluene to form 2-octyltoluene (Simons and Basler, 31). 

Oxidation of thiochromones does not lead to the sulfoxide or sulfone derivatives these are better prepared from the corresponding thiochromanones by oxidation followed by bromination and dehydrobromination. The 1-oxide is an extremely reactive species and gives a Diels-Alder adduct with butadiene. The 1,1-dioxide is also very reactive. Photolysis in benzene affords a 2 1 adduct in 30% yield (116) (79TL1097) via an initial [2 + 2] addition followed by a Diels-Alder reaction. Simple [2 + 2] addition is found with cyclohexene. 

Even though n-hexane is a minority hydrogenolysis product, it is a reliable measure of the degree of hydrogenolysis because of its ease of mass spectro-metric detection and it is not formed in a background reaction with the walls of the reaction chamber. Besides the saturated hydrogenolysis products and benzene, we found the olefinic products cyclohexene, ethylene, and propylene. Cyclohexene is an intermediate in the dehydrogenation to benzene and its various reactions will be discussed separately in the next section. The olefinic product distribution of ethylene propylene cyclohexene benzene is 10 1 0.5 1. 

Assume you have two unlabeled bottles, one with cyclohexene and one with benzene. How could you tell them apart by doing chemical reactions ... 

Although the first example of an asymmetric Kharasch-Sosnovski reaction with a chiral perester was reported as early as 1965 [17], major advances have only been made in the last ten years. In the early 1990s, Muzart carefully reinvestigated earlier results obtained by Araki and Nagase [18]. After intensive optimization of the reaction conditions, the acyloxylation of cydopentene and cyclohexene gave products with up to 59 and 45 % ee, respectively. The best conditions for the oxidation of cyclohexene were found to involve the use of 5 mol% copper oxide, 10 mol% proline (1), and tert-butyl perbenzoate/benzoic acid in benzene under reflux (Scheme 2) [19]. 

Benzene is reduced in 95% current yield to a mixture of 23% cyclohexadiene, 10% cyclohexene and 67% cyclohexane. HMPTA as a solvent additive seems to play a dual role. Firstly it is selectively adsorbed at the cathode surface, thereby preventing hydrogen evolution from the protic solvent. Thus it permits the attainment of a potential sufficiently cathodic for the generation of the solvated electron. It secondly stabilizes the solvated electron, thus suppressing its reaction with protic solvents (eq. (130) ). With decreasing HMPTA concentration in the electrolyte the current efficiency for reduction decreases and hydrogen evolution dominates. In pure ethanol the current efficiency is less than 0,4%. 

Michael BD, Hart EJ. The rate constants of hydrated electron, hydrogen atom, and hydroxyl radical reactions with benzene, 1,3-cyclohexadiene, 1,4-cyclo-hexadiene, and cyclohexene. J Phys Chem 1970 74 2878-2884. 

Interest in the photochemistry of the phthalimide systems has continued. The phthalimide derivatives (316) are phot ochemically reactive and on irradiation in acetone yields the cyclized products (317). The reaction involves hydrogen abstraction to yield the biradical (318) which subsequently bonds to afford the observed products. A recent study has examined the behaviour of the anion (319) in an attempt to reduce electron transfer processes. In t-butanol irradiation affords the solvent addition product (320) as the principal product presumably by a free radical path. Minor products (321) and (322) are also formed but are probably artefacts of the work-up procedure. Irradiation of (319) in methanol with added cyclohexene follows a different reaction path. In this system the reaction with methanol is minor while the dominant reaction is addition of the alkene to afford the adduct (323) in 20 % yield. The Dewar benzene derivative (324) is photocheraically unstable and irradiation affords t etramet hyl cyclobutadiene. ... 

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