MCQ
Among the given compounds, the correct dehydration order is :
- ✓$I < II < III < IV$
- B$II < III < IV < I$
- C$I < III < IV < II$
- D$I < II < III = IV$
✓
Answer
Correct option: A.
$I < II < III < IV$
a
Dehydration order is according to the stability of their intermediate. Benzylic carbocation is most stable due to resonance so $IV$ has the highest order. As allylic carbocation are more stable than $2^{\circ}$ carbocation, so the order is $III\, >\, II$.
Dehydration order is according to the stability of their intermediate. Benzylic carbocation is most stable due to resonance so $IV$ has the highest order. As allylic carbocation are more stable than $2^{\circ}$ carbocation, so the order is $III\, >\, II$.
Phenyl carbocations are least stable, so the order is $I\, <\, II\, < \,III \,<\, IV$.
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