Arrange the following in order of C-Br bond s | vedclass

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(C) The $C-Br$ bond strength in a polar solvent is inversely proportional to the stability of the carbocation formed after the dissociation of the $Br

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$IV < III < II < I$

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(C) The $C-Br$ bond strength in a polar solvent is inversely proportional to the stability of the carbocation formed after the dissociation of the $Br^-$ ion. More stable the carbocation,weaker is the $C-Br$ bond. $(I)$ and $(II)$ form cyclohexadienyl cations. $(III)$ and $(IV)$ form cyclopentadienyl cations. The cyclopentadienyl cation is anti-aromatic ($4n \pi$ electrons,$n=1$,total $4\pi$ electrons),making it highly unstable. The cyclohexadienyl cation is non-aromatic and relatively more stable than the cyclopentadienyl cation. Comparing $(I)$ and $(II)$: $(I)$ has a methyl group which stabilizes the carbocation via inductive effect and hyperconjugation,making the carbocation more stable and the $C-Br$ bond weaker. Thus,$C-Br$ bond strength: $II > I$. Comparing $(III)$ and $(IV)$: $(III)$ has a methyl group which stabilizes the carbocation,making the $C-Br$ bond weaker. Thus,$C-Br$ bond strength: $IV > III$. Since the cyclopentadienyl cation is much less stable (anti-aromatic) than the cyclohexadienyl cation,the $C-Br$ bond in $(III)$ and $(IV)$ is much stronger than in $(I)$ and $(II)$. Therefore,the order of $C-Br$ bond strength is $I Re-evaluating: Stability of carbocation: $I > II > III > IV$. Bond strength: $IV > III > II > I$.

Arrange the following in order of $C-Br$ bond strength in a polar solvent. The structures are as follows:
$(I)$ $1$-methylcyclohexa-$2,4$-dienyl bromide
$(II)$ cyclohexa-$2,4$-dienyl bromide
$(III)$ $1$-methylcyclopenta-$2,4$-dienyl bromide
$(IV)$ cyclopenta-$2,4$-dienyl bromide

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Arrange the following in order of $C-Br$ bond strength in a polar solvent. The structures are as follows: $(I)$ $1$-methylcyclohexa-$2,4$-dienyl bromide$(II)$ cyclohexa-$2,4$-dienyl bromide$(III)$ $1$-methylcyclopenta-$2,4$-dienyl bromide$(IV)$ cyclopenta-$2,4$-dienyl bromide