The structural formula of the carbocation formed by protonation of either C-2 or C-3 in 1,3-cyclopentadiene is to be written for verifying that it is not allylic and hence not as stable as the one formed by protonation of either C-1 or C-4 Concept Introduction: > The allyl group contains the unit CH=CH-CH 2 . > A sp 3 carbon atom of an allyl group is the allylic carbon atom. > Carbon atoms which are adjacent to the double bonded carbon atoms are the allylic carbon atoms > Allylic carbocations are more stable than the corresponding alkyl carbocations because the vinyl group (CH 2 =CH) is a better carbocation-stabilizing substituent than alkyl groups.

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Chapter 11.10, Problem 15P

Interpretation Introduction

Interpretation:

The structural formula of the carbocation formed by protonation of either C-2 or C-3 in 1,3-cyclopentadiene is to be written for verifying that it is not allylic and hence not as stable as the one formed by protonation of either C-1 or C-4

Concept Introduction:
>
The allyl group contains the unit CH=CH-CH2 .
>
A sp3 carbon atom of an allyl group is the allylic carbon atom.
>
Carbon atoms which are adjacent to the double bonded carbon atoms are the allylic carbon atoms
>
Allylic carbocations are more stable than the corresponding alkyl carbocations because the vinyl group (CH2=CH) is a better carbocation-stabilizing substituent than alkyl groups.

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