Chemical reactivity unsaturated compound addition reactions

Thus, in spite of its lack of reactivity, iodine reacts chemically with unsaturated compounds, whereby the silica gel of the TLC layer can sometimes be assigned a catalytic role [11, 12]. Irreversible oxidations and electrophilic substitution and addition reactions have been observed on the interaction of iodine with tertiary nitrogen compounds such reactions possibly depend on particular steric relationships or are favored by particular functional groups [13, 14]. 

The single bonds between carbon and hydrogen atoms in organic compounds are not highly reactive. However, these compounds do participate in a variety of chemical reactions, one of which is called a substitution reaction. A substitution reaction is a reaction in which one or more atoms replace another atom or group of atoms in a molecule. Another type of reaction involving organic compounds is an addition reaction in which an atom or molecule is added to an unsaturated molecule and increases the saturation of the molecule. 

The 7t sulfuranes are isoelectronic with diazo compounds and therefore may be expected to possess very similar chemical reactivity. However, the zwitteridnic character of these intermediates is greater than that of diazo compounds thereby facilitating their nucleophilic additions to carbonyl groups and Michael acceptors such as a,p-unsaturated carbonyl systems. DiphenylsulfoniumallyMe serves as a typical example. ) Thus, it reacts with 4-f-butylcyclohexanone to give the epoxide with predominantly the trans configuration and with methyl acrylate to yield the cyclopropane after 1,3-elimination. Many new t5 es and new reactions of n... 

Aromaticity is one of the most fascinating popular qualitative chemical concepts in chemistry Michael Faraday isolated benzene by distillation in 1825. He noticed that although benzene is an unsaturated compound with H C 1 1 it is much less reactive than the related unsaturated aliphatic compounds. Moreover, it undergoes substitution reactions rather than addition reactions exhibited by alkenes and alkynes. Eilhard Mitscherlich synthesized benzene by heating benzoic acid with lime. 

In general, aromatic compounds tend to react in such a fashion as to retain the aromatic nucleus by undergoing substitution rather than addition reactions. This unusual (for unsaturated systems) pattern of reactivity is taken as an indication of the special stability of aromatics. Chemical reactivity is not a particularly good criterion for aromaticity as it is difficult to quantify and for many aromatics the preferred reaction motif is addition. 

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