Identify the correct reactivity order for E_2 | vedclass

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Question

(B) The $E_2$ reaction involves the elimination of a proton and a leaving group to form a double bond. The rate of $E_2$ elimination is significantly

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$ii > i > iii$

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(B) The $E_2$ reaction involves the elimination of a proton and a leaving group to form a double bond. The rate of $E_2$ elimination is significantly enhanced if the resulting product is aromatic or anti-aromatic,as the transition state is stabilized by conjugation.$(i)$ Elimination in $8$-chlorocycloocta-$1,3,5$-triene leads to cyclooctatetraene,which is a stable $8\pi$ electron system (non-aromatic,but highly conjugated).(ii) Elimination in $3$-chlorocyclohexa-$1,4$-diene leads to benzene,which is highly aromatic and stable. This provides a very strong driving force for the reaction.(iii) Elimination in $3$-chlorocyclobutene leads to cyclobutadiene,which is anti-aromatic ($4\pi$ electrons) and highly unstable. This makes the reaction very slow.Therefore,the reactivity order is $(ii) > (i) > (iii)$.

Column-$I$	Column-$II$
$(i)$ $R-Cl + NaI \xrightarrow{\text{dry acetone}} R-I + NaCl$	$(a)$ Swarts reaction
$(ii)$ $CH_3-Br + AgF \xrightarrow{\Delta} CH_3-F + AgBr$	$(b)$ Wurtz reaction
$(iii)$ $R-X + Mg$ $\xrightarrow{\text{dry ether}} R-Mg-X$ $\xrightarrow{H_2O} RH + Mg(OH)X$	$(c)$ Finkelstein reaction
	$(d)$ Grignard reaction

Identify the correct reactivity order for $E_2$ reaction with alc. $KOH$ for the following compounds:
$(i)$ $8$-chlorocycloocta-$1,3,5$-triene
(ii) $3$-chlorocyclohexa-$1,4$-diene
(iii) $3$-chlorocyclobutene

Similar Questions

The following reaction is supposed to take place through the $S_N1$ mechanism: $CH_3-C(Ph)(OH)-CH_2-CH_3 \xrightarrow{HI} \text{products}$. If the configuration of the substrate is $D$,then the configuration of the products will be:

Which of the following statements is correct regarding the rate of hydrolysis of the compounds $(A)$ and $(B)$ by $S_N1$ reaction?

What is the product formed when $1$-bromo-$3$-chlorocyclobutane reacts with $2$ moles of sodium in ether?

Which of the following reactions is an example of an $S_{N}2$ reaction?

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Identify the correct reactivity order for $E_2$ reaction with alc. $KOH$ for the following compounds:$(i)$ $8$-chlorocycloocta-$1,3,5$-triene(ii) $3$-chlorocyclohexa-$1,4$-diene(iii) $3$-chlorocyclobutene