Allylic and benzylic? (Qvault OChem)

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TheEpicFruitCake

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The following carbocation is
image1054.png


A: Primary benzylic

B: Allylic

C: Secondary

D: Secondary benzylic

E: Benzylic

Explanation
This is a secondary benzylic carbocation. It is adjacent to a benzene ring and attached to an additional carbon. Because it is a benzylic carbocation, the positive charge can be distributed throughout the ring. The term benzylic generally refers to any substituent, charge, or electron that is on a carbon that is directly attached to a benzene ring. Allylic refers to any substituent, charge, or electron that is on a carbon directly attached to a carbon-carbon double bond.

I'm not understanding how there is only 1 correct answer here. Can't this carbon be considered allylic, benzylic and secondary benzylic? I can see how D is better than E, but not B.
Thanks in advanced!

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Well it's not allylic because the double bond you see in the ring is not a complete double bond. It's more of a 1.5 bond because the electrons are shared equally throughout the ring. For it to by allylic the C would have to be attached to a permanent C=C as in C-C=C.

Edit: ^^^^ ixyz's link above explains it perfectly.
 
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