Stability of organic compounds

As chemists learned more about the effects of structure on the stability of organic compounds, it became apparent that Dewar benzene is much less stable than benzene. Not only does it have a considerable amount of angle strain, but it also has none of the stabilization due to aromaticity that benzene has. Because of these factors, Dewar benzene is 71 kcal/mol (297 kJ/mol) less stable than benzene. Because the conversion of Dewar benzene to benzene is so exothermic and involves an apparently simple electron reorganization, many chemists believed that the isolation of this strained isomer would prove to be impossible. They thought that if it were prepared, it would rapidly convert to benzene. In support of tills view, numerous attempts to synthesize Dewar benzene met with failure. 

Chemical stabilization is the alteration of the chemical form of the contaminants to make them resistant to aqueous leaching. Solidification/Stabilization processes are formulated to minimize the solubility of metals by controlling pH and alkalinity. Entrapment or microencapsulation may immobilize anions, which are more difficult to bind in insoluble compounds. Chemical stabilization of organic compounds maybe possible, but the mechanisms involved are poorly understood [22]. 

We recall (Sec. 2.6) that the heat of combustion is the quantity of heat evolved when one mole of a compound is burned to carbon dioxide and water. Lik heats of hydrogenation (Secs. 6.4 and 8.16), heats of combustion can often fur nish valuable information about the relative stabilities of organic compounds. Let us see if the heats of combustion of the various cycloalkanes support Baeyer s proposal that rings smaller or larger than cyclopentane and cyclohexane are unstable. 

Most of the principles used to explain the acidity of compounds are also used to explain the reactivity and stability of organic compounds in general. Also, proton transfer reactions are often the first step in most organic reactions. For this reason, if we can thoroughly comprehend proton transfer, then we have a solid basis for understanding most organic reactions. 

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