Question

(A) $C{H}_3-\underset{\underset{C{H}_3}{|}}{C}H-C{H}_2-C{H}_2-OH$

(B) $C{H}_3-\stackrel{\underset{|}{OH}}{\underset{\stackrel{|}{C{H}_3}}{C}}-C{H}_2-C{H}_3$

(C) $C{H}_3\stackrel{\stackrel{C{H}_3}{|}}{CH}-\stackrel{\stackrel{OH}{|}}{CH}-C{H}_3$

The order of given alkanols $A,B,C$ in their reactivity towards acid catalysed dehydration is:

• A. $A>B>C$
• B. $B>A>C$
• C. $B>C>A$
• D. $C>B>A$

Answer 1

The correct option is C $B>C>A$

Carbocation formed during reaction are referred to the image above:

Therefore stability of carbocations have the order $3degree>2degree>1degree$ and $C{H}_3$ is $+$ group so, the order of stability is $:B>C>A$

(B) $C{H}_3-\stackrel{\underset{|}{OH}}{\underset{\stackrel{|}{C{H}_3}}{C}}-C{H}_2-C{H}_3\to C{H}_3-\stackrel{\underset{|}{\oplus }}{\underset{\stackrel{|}{C{H}_3}}{C}}-C{H}_2-C{H}_3$ $\left(2^o\right)$

(C) $C{H}_3-\stackrel{\stackrel{C{H}_3}{|}}{C}H-\stackrel{\stackrel{OH}{|}}{C}H-C{H}_3\to C{H}_3-\underset{\underset{C{H}_3}{|}}{C}-\underset{\oplus }{Ch}-C{H}_3\underset{\left(2^o\right)}{C{H}_3}$