Isomerism alicyclic compounds

Alicyclic compounds exhibiting conformational isomerism are also subject to considerable medium effects [80-83, 182, 184]. 

Alicyclic compounds can also display cis-trans isomerism. As an example of a geometric isomer due to a ring structure, consider 1,2-dichlorocyclohexane ... 

A variety of isomeric or closely related mixtures of organic compounds are often found when manufacturing chemical and pharmaceutical products. However, it is usually necessary to separate these molecules in order to obtain the expected functionality of the products. Conventional methods such as distillation, extraction and crystallization might be difficult to use since the molecules to be separated might have very close chemical and physical properties. Hydrotropes are known to be selective in the solubilization of compounds and as mentioned earlier, do not perform so generally as surfactants. It has been found that the solubility enhancement in water by adding the hydrotrope sodium xylene sulfonate (SXS) will vary for different isomers such as o- and /7-nitrochlorobenzene, as well as for o- and p-dichlorobenzene (24). In this case, the c -isomer is more soluble than the p-isomer. Higher solubilities have also been reported for aromatic compounds when compared to aliphatic and alicyclic compounds (24). This selective... 

In concluding this account of the published information on the effect of cis,trans isomerism in compounds of the alicyclic series on their reactivity at electrodes it can be mentioned that differences in the behavior of the isomers arise from both thermodynamic and nonthermodynamic reasons. 

The conversion of a chemical with a given molecular formula to another compound with the same molecular formula but a different molecular structure, such as from a straight-chain to a branched-chain hydrocarbon or an alicyclic to an aromatic hydrocarbon. Examples include the isomerization of ethylene oxide to acetaldehyde (both C2H40) and butane to isobutane (both C4H10). 

Cyclic hydrocarbons are called cycloalkanes they are examples of alicyclic (g/ phatic cyclic) compounds. Cycloalkanes, having the general formula are isomeric with alkenes but, unlike... 

It has been found quite recently that the isomerization to carbonyl compounds of oxiranes containing a rr-electron system is catalyzed by certain metal complexes. The experimental data acquired so far suggest that only the penta-cyanocobalt complexes are active towards the isomerization of aliphatic and alicyclic oxiranes. ... 

Cycloaddition of 1,3-dipolarophiles to alkynes for the synthesis of diazo compounds can also be applied to reaction of diazoalkanes with alkynes (2-91). 2-Diazopropane and 1,2-diarylethynes readily form 3//-pyrazoles (2.229). These pyrazoles isomerize photochemically to the 4-diazo-2-methyl-3,4-diarylbutenes (2.230), i.e., to a vinyldiazo compound (Pincock et al., 1973 Arnold et al., 1976 Leigh and Arnold, 1979). Some cyclopropene (2.231) is formed in a consecutive dediazoniation, i. e., by cyclization of the carbene formed. The method is not useful for unsymmetrically substituted alkynes because these cycloadditions are not regiospecific. It is, however, applicable to the synthesis of diazoalkenes with alicyclic... 

Protonated aliphatic/alicyclic nitro compounds have not been studied to the same extent as the nitroarenes. However, the isomeric [C2H6N02]+ ions and their rearrangement in the gas phase have been subject to studies . The protonated ethyl nitrite and nitroethane were generated by proton transfer from different Br0nsted acids. In addition, protonated ethyl nitrite was obtained as a result of addition of NO+ to ethanol. The existence of two different [C2H6N02]" structures, i.e. protonated ethyl nitrite and protonated nitroethane, was demonstrated. Slow isomerization of protonated nitroethane to protonated ethyl nitrite has been elucidated see Scheme 40. 

As an example for the isomerism in which the C-atom is alicyclical, we have the compounds synthesised by Wallach ... 

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