Methylcyclohexane chlorination

Figure 24. Autooscillations of rate of methylcyclohexane chlorination in its equimolar mix with molecular chlorine. Initial temperature is 45 K. Radical concentration created with prephotolysis is 4 X 10 cm"...

Aware of the enhanced reactivity of trivalent [( ArO)3tacn)U] towards non-innocent solvents, such as ethers and chlorinated solvents, the reactivity of this molecule was challenged by exposure to more inert solvents like alkanes. Remarkably, recrystallization of 4 -bu u pentane solutions containing various cycloalkanes, i.e., methylcyclohexane, afforded the coordination of one cycloalkane molecule to the electron-rich U center (Scheme 4) (37). 

Kostiainen (1995) identified more than 200 individual VOCs indoors in 26 houses. In addition, they compared the VOC concentrations in normal houses to those where complaints of odors or illness had been registered. A number of different VOCs were present at increased concentrations in the houses with complaints compared to the normal houses these included a variety of aromatic hydrocarbons, methylcyclohexane, n-propylcyclohexane, terpenes, and chlorinated compounds such as 1,1,1-trichloroethane and tetra-chlorethene. 

The solid-state environment prevents diffusion of radicals, so reactions are only possible with neighboring Cl2 molecules. Reaction (9.15) can therefore occur only in clusters (RH-C12) , where > 2. Products are observed only when the mole fraction of chlorine in the mixture is greater than 0.1. The k(T) dependence includes an Arrhenius region (60-90 K) in which the activation energy (2-4 kcal/mol) is 1.5-2 times larger than in the corresponding gas-phase reactions. The low-temperature plateau occurs below 40-50 K where kc is 5 x 10-3 s-1 and 2 x 10 2 s-1 for the radicals of n-butylchloride and methylcyclohexane, respectively. 

Methylcyclohexane (MCH) + C12 When frozen, a solution of Cl2 in MCH (1 3) vitrifies (Tg 93 K). The chain chlorination does not occur until the system is heated into the devitrification region. The heat of reaction is 130kJ/mole.14... 

One of the two chair structures of cis-l-chloro-3-methylcyclohexane is more stable than the other by 15.5 kJ/mol (3.7 kcal/mol). Which is it What is the energy cost of a 1,3-diaxial interaction between a chlorine and a methyl group ... 

Draw the structures and provide systematic names for a-c by substituting a chlorine for a hydrogen of methylcyclohexane ... 

Would chlorination or bromination of methylcyclohexane produce a greater yield of 1-halo-1-methylcyclohexane ... 

Halo-1-methylcyclohexane is a tertiary alkyl halide, so the question becomes, Will bromination or chlorination produce a greater yield of a tertiary alkyl halide Because bromination is more selective, it will produce a greater yield of the desired compound. Chlorination will form some of the tertiary alkyl halide, but it will also form significant amounts of primary and secondary alkyl halides. 

Evidently there is not much difference in the overall conversions of styrene in polymerizations using rcrt-butyl chloride and 3-chloro-1 -butene coinitiators under similar conditions (Figs. 5 and 6). This is expected because of the similar reactivities of the tertiary and substituted allylic chlorines in these coinitiator molecules. In addition, since rates of the various individual competing reactions in nonpolar solvents (i.e. methylcyclohexane and n-heptane) are expected to be higher at higher temperatures (20° C) than at lower temperatures (—50° C), and if the propagation or initiation rate overrides that for termination, it would not be unexpected to find that yields increase with increasing temperature. Also, it is... 

It is important to note that when El elimination is effected on the epimeric chloro-derivative [neomenthyl chloride, (l/ 35,45)-3-chloro-4-(l-methylethyl) methylcyclohexane]. Scheme 7.33, which has the chlorine axial and the two alkyl substituents equatorial, and where, as a consequence of that arrangement, there are now two anti (or antarafacial) and axial protons situated P to the chlorine (Cl), the same product mixture is obtained, but now, with anri-elimination possible, the ratio of 3-menthene 2-menthene is 98 2. 

The diaxial conformation of c -l-chloro-3-methylcyclohexane is 16 kJ mole less stable than the diequatorial conformation. Why is this value larger than the sum of the steric strains of a chlorine atom and a methyl group ... 

Markovnikov Addition of Hydrochloric Acid to Alkenes. 1-Chloro-l-methylcyclohexane, the foimal Markovnikov adduct of hydrochloric acid and 1-methylcyclohexene, becomes largely predominant when Sulfuryl Chloride is the chlorine source and KIO the solid acid. The reaction at 0°C, in dry methylene chloride, is complete within 2 h (eq 10). 

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