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(A) Nucleophilic aromatic substitution $(S_NAr)$ is facilitated by electron-withdrawing groups (EWGs) at the ortho and para positions relative to the

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$3 > 4 > 1 > 2$

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(A) Nucleophilic aromatic substitution $(S_NAr)$ is facilitated by electron-withdrawing groups (EWGs) at the ortho and para positions relative to the leaving group $(-Br)$,as they stabilize the Meisenheimer complex intermediate through resonance ($-M$ effect).$1$. $1$-bromo-$2$-nitrobenzene: One $-NO_2$ group at the ortho position ($-M$ effect).$2$. $1$-bromo-$3$-nitrobenzene: One $-NO_2$ group at the meta position (only $-I$ effect,no resonance stabilization of the intermediate).$3$. $1$-bromo-$2,4$-dinitrobenzene: Two $-NO_2$ groups at ortho and para positions (strong $-M$ effect from both).$4$. $1$-bromo-$3,4$-dinitrobenzene: One $-NO_2$ group at the para position ($-M$ effect) and one at the meta position ($-I$ effect).Comparing the stabilization:Compound $3$ has two groups providing resonance stabilization,so it is the fastest.Compound $4$ has one group providing resonance stabilization (para),so it is faster than $1$.Compound $1$ has one group providing resonance stabilization (ortho),but it is generally slightly less reactive than para-substituted due to steric hindrance,however,both $1$ and $4$ are faster than $2$.Actually,comparing $1$ and $4$: $4$ has a para-nitro group (strong $-M$) and a meta-nitro group $(-I)$,while $1$ has an ortho-nitro group $(-M)$. The para-nitro group in $4$ provides better resonance stabilization than the ortho-nitro in $1$. Thus,the order is $3 > 4 > 1 > 2$.

Rank the following compounds in order of decreasing rate of reaction with alkoxide ion $(CH_3CH_2O^{-})$ in a nucleophilic aromatic substitution reaction:
$1$. $1$-bromo-$2$-nitrobenzene
$2$. $1$-bromo-$3$-nitrobenzene
$3$. $1$-bromo-$2,4$-dinitrobenzene
$4$. $1$-bromo-$3,4$-dinitrobenzene

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Rank the following compounds in order of decreasing rate of reaction with alkoxide ion $(CH_3CH_2O^{-})$ in a nucleophilic aromatic substitution reaction:$1$. $1$-bromo-$2$-nitrobenzene$2$. $1$-bromo-$3$-nitrobenzene$3$. $1$-bromo-$2,4$-dinitrobenzene$4$. $1$-bromo-$3,4$-dinitrobenzene