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2-Phenylethanol naming convention doesn't make sense

What doesn't seem to make sense to me is how the naming convention gives it to be 2-phenylethanol.

I'm struggling to understand why.

Please explain.

By my understanding, the fact that it is a long chain of CH2CH2OH is ethanol but why is it 2-phenylethanol when it is on carbon 1 of the ring?

(edited 7 years ago)

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Reply 1

Shawman

I'm not sure (always hated IUPAC naming) but I think it may be because the OH is on C1 and so the phenyl ring is on C2

Reply 2

nwmyname

Original post by Shawman

I'm not sure (always hated IUPAC naming) but I think it may be because the OH is on C1 and so the phenyl ring is on C2

That was my guess. Hmm you seem to be right.
Iupac naming is just so weird at times.

Because I know that the OH group is functional, so the benzene becomes a phenyl, but like I said (and you might be right) is why it is 2-phenylethanol.

Hmm, you seem right on second thoughts. We'll wait for someone else to confirm it.

Reply 3

Kvothe the Arcane

The benzene group is attached to Carbon 2 of the ethanol.

You are mistaken.
The molecule below is 1-phenylethanol.

The number prefix refers to which carbon of the long chain has a H substituted with the functional group in question.

(edited 7 years ago)

Reply 4

Shawman

Original post by nwmyname

Having recovered slightly more from my hangover I'm more certain of my explanation.*

Reply 5

oShahpo

There are two ways of naming this, only one is IUPAC correct.
either the alcohol takes precedence, and the phenyl group becomes just an added branch, in this case you start counting carbons from the OH. So the carbon bonded to the phenyl group is the second carbon and you get 2-Phenylethanol.
OR
You could treat the chain as the substituent group, if you do that, you will fall into a lot of trouble. How do you indicate which carbon of ethanol is bonded to the benzene? And what the hell is the substituent name of ethanol? ethanyl? ethanoyl? They're all taken. So stick to the first one as it's the IUPAC certified one.