Cyclohexane-methylcyclopentane

Tantalum hydride(s) also catalyzes the hydrogenolysis of cyclic alkanes (substituted or not) but the reachvity order decreases with the cycle size as cycloheptane > methylcyclohexane > cyclohexane > methylcyclopentane > cyclopentane for the latter no reaction is actually observed (Figure 3.8). Activity decreases with hme and becomes low after 20 h. 

Figure 3.8 Conversion with time in the hydrogenolysis of cycloalkanes (19Torr, 14.5 equiv.) catalyzed by (=SiO)2TaH (3) at 160°C under hydrogen (470Torr) cycloheptane ( ), methylcyclohexane ( ), cyclohexane ( ), methylcyclopentane (A) and cyclopentane (x).

Cyclohexane-methylcyclopentane isomerization21 can be depicted as in Scheme 4.2. The isomerization of substituted cyclopentanes and cyclohexanes to polymethylcyclohexanes similarly occurs by way of a series of consecutive steps... 

Cyclohexane can be acylated with acetyl chloride and AICI3 to yield l-acetyl-2-methylcyclopentene in 37% yield.127 Alkanes, such as 2-methylbutane, cyclohexane, methylcyclopentane, and methylcyclohexane, are easily acylated with a,p-unsaturated acyl chlorides in the presence of A1C13 and a hydride acceptor to afford mono- or bicyclic products after secondary transformations.128 Isoalkanes (isopentane, 2-methylpentane, 3-methylpentane, 2,3-dimethylbutane) undergo diacylation and eventually form pyrilium salts under Friedel-Crafts acylation conditions with acetyl chloride or acetic anhydride.129... 

Hexane Isohexanes Cyclohexane Methylcyclopentane —. K-Hexene — — Isohexenes... 

Figure 6.39 Data for structure H hydrates of methane + nitrogen with cyclohexane, methylcyclopentane, and methylcyclohexane.

Cracking and disproportionation in the reaction of hexane could be suppressed by the addition of cycloalkanes (cyclohexane, methylcyclopentane, cyclopentane).101 Furthermore, 3-methylpentane and methylcyclopentane also reduced the induction period. These data indicate that reactions are initiated by an oxidative formation of alkene intermediates. These maybe transformed into alkenyl cations, which undergo cracking and disproportionation. When there is intensive contact between the phases ensuring effective hydride transfer, protonated alkenes give isomerization products. 

The results obtained in this study indicate that in Al-ffee H-boralite (BOR 1) only weak BrOnsted acid sites (Si—OH—B) are present. They are active only in cyclohexanol dehydration. Their catalytic activity is, however, relatively low. The insertion of A1 into the framework results in the creation of strong Bronsted acid sites. Most probably they are Si—OH—Al, the same as in zeolites. The IR band which could be characteristic of such Si—OH—Al (at about 3610 cm ) was not seen in the spectrum because of the very low concentration of these hydroxyls. The catalytic activity of Si—OH—Al is much higher that of Si—OH - B. Contrary to Si—OH -B, Si—OH— A1 are active in consecutive reactions of cyclohexene (isomerization and disproportionation). Cyclohexene isomerization (to methylcyclopentenes), a typical carbenium ion reaction is catalysed by strong Brdnsted acid sites even at temperatures as low as 450 K. The same strong Bronsted acid sites catalyse also cyclohexene disproportionation (to cyclohexane, methylcyclopentane and coke). Our earlier... 

Saturated normal hydrocarbons C H2n+2 Ethylene Ethylenes C H 2n with double bond in terminal position Cyclohexane Methylcyclopentane Cyclohexene Cyclohexadiene Benzene... 

Cycloalkanes also undergo related acid-catalyzed rearrangements. Higher coordinate carbocations again play a key role in the mechanism as shown in the cyclohexane-methylcyclopentane rearrangement. ... 

Whereas the cyclohexane-methylcyclopentane isomerization involves initial formation of the cyclohexyl (methylcyclopentyl) cation, that is, via protolysis of a C-H bond, it should be mentioned that in the acid-catalyzed isomerization of cyclohexane, up to 10% hexanes are also formed, and this is indicative of C-C bond protolysis (Scheme 6.10). 

Names in order cyclohexane methylcyclopentane ethylcyclobutane 1,1-dimethylcyclobutane 1,2-dimethylcyclobutane 1,3-dimethylcyclobutane. 

Cyclohexadiene Biallyl Cyclohexene Allyl sulfide Cyclohexane Methylcyclopentane... 

The combined liquid effluent from the fluidized-bed run was collected, and a complete analysis was made. The data are shown in Table V. The extensive isomerization taking place is of some interest all of the C6 paraffins except diisopropyl are present in the effluent, along with cyclohexane-methylcyclopentane, MCH-dimethylcyclopentane, etc. Nickel is, of course, known to have isomerizing activity, but in addition the catalyst may be functioning as a dual-function isomerization catalyst. 

The catalytic properties of metal-zirconium phosphate solid has also been investigated (21, 349). The catalysts were prepared by the ion exchange of zirconium phosphate with copper, nickel, and chromium ions. Cataljdic dehydration of 2-propanol was studied at 160°-350°C, with zirconium phosphate itself giving the highest activity, yielding 97% propylene at 230°-240°C. Introduction of Cu +, Ni +, and Cr " decreased the dehydrating properties, and also decreased the catalytic isomerizing properties when tested with the cyclohexane-methylcyclopentane isomerization. The introduction of copper and nickel improved the dehydration properties of zirconium phosphate when tested on ethylbenzene. 

Arts. In the order given, left to right, the compounds are cyclohexane, methylcyclopentane, ethylcyclo-butane, 1,2-dimethylcyclobutane, 1,3-dimethylcyclobutane, 1,1-dimethylcyclobutane, n-propyl-cyclopropane, isopropylcyclopropane, 1-ethyl-1-methylcyclopropane, l-ethyl-2-methylcyclopropane, 1,2,3,-trimethylcyclopropane. 

A plot of the resultant A O, against ring size is shown in Fig. 1, and from this it is seen that it is impossible (zI(t is positive) to polymerize cyclohexanes, methylcyclopentane, or 1,1-dimethyl-cyclopentane, at 25 C. Although in these cases the A S values are less negative than for the three- and four-membered ring polymerizations, the AH values are insufficiently negative to produce negative A O values. 

Methylbenzophenone o-Methyl benzoyl benzoate Methyl bromide 3-Methyl-2-butanol Methyl cyanoacetate Methyl cyclohexane Methylcyclopentane Methylene iodide Methyl 2-furoate Methyl heptenone... 

The Hydra process was originally based on platinum catalysts, modified with a lithium salt more recently, nickel catalysts have been used. Maintaining a low residence time ensures that, despite the high reaction temperature, the cyclohexane/ methylcyclopentane equilibrium cannot be achieved. 

Problem 5.L (a) Write the structures for n-hexane and as many of its isomers as you can. (b) Draw the structure of cyclohexane, methylcyclopentane, the isomers of dimethylcyclobutane, and isomers of trimethylcyclopropane. Note that they all correspond to CeHi2. (c) Draw the structure of bicyclo[2.2.0]hexane. Are there any other bicyclic isomers corresponding to CeHio ... 

Inglese, A. Grolier, J.-P. E. Excess enthalpies of binary mixtures containing heptane, decane, cyclopentane, cyclohexane, methylcyclopentane, benzene, or tetrachloromethane Int. DATA Ser., Sel. Data Mixtures, Ser. A1975,3,98-106... 

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