Alylic vs. benzylic vs. vinylic

[brlin]

So I've never been able to keep these terms straight and I'm having trouble finding a clear cut answer: Alylic vs. benzylic vs. vinylic groups?

Here are my best guesses:
Allylic: compound bound to a C bound to a C=C
So X in C=C-C-X would be an allylic group. But would the C bound to the 2 carbons in a double bond also be considered an allylic carbon?

Benzylic:
Benzene-C-X, where X is the benzylic group

Vinylic: No idea. (Edit: would "X" in C=C-X be vinylic?)

On the same train of thought, claisen rearrangements utilize" vinylic allyl ethers". I know what compound that's referring to, but how did they arrive at that nomenclature?

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[akim6890]

You're mostly correct on everything. There's a distinction between an allylic/vinyllic carbon and an allylic/vynyllic group because allylic/vynyllic groups are those that are attached to allylic/vynyllic carbons. So the two carbons that participate in a double bond are vinylic and carbons attached to those are allylic.

If you look at the structure of a vynylic allyl ether, it'll make sense. An ether tells you there are two alkyl substituents on either side of the oxygen. On one side of the ether is a allylic carbon and on the other side is a vynylic carbon making a vynylic allyl ether. = O -- =

 

[brlin]

Ok, so to make sure I've got this all straight, do you mind taking a look at the below image I attached?

Can the allylic carbon that I drew technically also be a vinylic group, because its attached to the vinylic carbon?

Also, is there a distinction between benzylic carbons and benzylic groups? I'm assuming its analogous to the distinction between allylic carbon and an allylic group?

Sorry for the deluge of questions

 

[ChemTutor]

Ok, so to make sure I've got this all straight, do you mind taking a look at the below image I attached?

Can the allylic carbon that I drew technically also be a vinylic group, because its attached to the vinylic carbon?

Also, is there a distinction between benzylic carbons and benzylic groups? I'm assuming its analogous to the distinction between allylic carbon and an allylic group?

Sorry for the deluge of questions

-CH2- is not considered to be a group. so it would not be called a vinylic group.

 

[heartsavior]

Ok, so to make sure I've got this all straight, do you mind taking a look at the below image I attached?

Can the allylic carbon that I drew technically also be a vinylic group, because its attached to the vinylic carbon?

Also, is there a distinction between benzylic carbons and benzylic groups? I'm assuming its analogous to the distinction between allylic carbon and an allylic group?

Sorry for the deluge of questions

Try not to get too caught up with the terminology. Focus more on the implications of such chemical representations. That being said, the carbon you drew is the first atom of one of two substituents of one of the two vinyl carbons. It is also an allylic position. -CH2-Cl is the substituent. Either of the two -Hs on this carbon are Allylic, because they are attached to a carbon considered the allylic position. The convention is analogous to a primary, secondary, or tertiary hydrogens and the carbon substitution of the carbons they are directly attached to.