Inductive effect of chlorine

As can be seen by comparing these two examples to 37 acetaldehyde, the inductive effect of chlorine shifts the... 

In vinyl chloride, inductive effect of chlorine reduces the electron availability of the 7T bond to retard severely the rate of reaction. On the other hand, conjugation returns some electron density to the site p to chlorine, which becomes the preferred site of hydroboration. 

Because the C—Cl bond is so long, the lone-pair orbital (3p) of chlorine and the -ir orbital of the carbonyl group do not overlap sufficiently to permit delocalization of a chlorine unshared pair. Not only is the carbonyl group of an acyl chloride not stabilized by electron-pair donation, the electron-withdrawing inductive effect of chlorine makes it more electrophilic and more reactive toward nucleophiles. 

In the structure on the left, the charge is somewhat stabilized by the inductive effects of the neighboring chlorine atoms. In contrast, the structure on the right is destabilized by the presence of methyl groups. Therefore, the structure on the left is more stable. 

The extra electron-withdrawing inductive effect of the electronegative chlorine atom is responsible for the greater acidity of chloroacetic acid by making the hydroxyl proton of chloroacetic acid even more positive than that of acetic acid. 

Also other Type B and C series from Table II are consistent with the above elimination mechanisms. The dehydration rate of the alcohols ROH on an acid clay (series 16) increased with the calculated inductive effect of the group R. For the dehydrochlorination of polychloroethanes on basic catalysts (series 20), the rate could be correlated with a quantum-chemical reactivity index, namely the delocalizability of the hydrogen atoms by a nucleophilic attack similar indices for a radical or electrophilic attack on the chlorine atoms did not fit the data. The rates of alkylbenzene cracking on silica-alumina catalysts have been correlated with the enthalpies of formation of the corresponding alkylcarbonium ions (series 24). Similar correlations have been obtained for the dehydrosulfidation of alkanethiols and dialkyl sulfides on silica-alumina (series 36 and 37) in these cases, correlation by the Taft equation is also possible. The rate of cracking of 1,1-diarylethanes increased with the increasing basicity of the reactants (series 33). 

In this case the waier attacks and hydrolyzes not a cation but a small, highly charged center (the tnvalent phosphorus atom) resulting from the inductive effect of the chlorine atoms. 

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