In which of the following reactions is Markow | vedclass

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(D) Markownikoff's rule states that in the electrophilic addition of $HX$ to an unsymmetrical alkene,the negative part of the addendum $(X^-)$ attache

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$O_2N - CH = CH_2 \xrightarrow[CCl_4]{HBr}$

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(D) Markownikoff's rule states that in the electrophilic addition of $HX$ to an unsymmetrical alkene,the negative part of the addendum $(X^-)$ attaches to the carbon atom with the fewer number of hydrogen atoms. This rule is based on the formation of the most stable carbocation intermediate. In the reaction of $O_2N - CH = CH_2$ with $HBr$,the $-NO_2$ group is a strong electron-withdrawing group ($-I$ and $-M$ effect). When $H^+$ attacks the terminal $CH_2$ group,it forms a carbocation at the carbon attached to the $-NO_2$ group $(CH_3 - CH^+ - NO_2)$. This carbocation is highly unstable due to the electron-withdrawing nature of the $-NO_2$ group. Consequently,the addition occurs in a way that avoids this unstable intermediate,effectively violating the standard Markownikoff's rule as the $Br^-$ attaches to the carbon with more hydrogen atoms to avoid the highly destabilized carbocation.

In which of the following reactions is Markownikoff's rule violated?

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