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Normally phenols have the $\ce{OH}$ group at the 1 or 4 position. Can they be made at 2 or 3 positions, where nitro groups and $\ce{-CN}$ can attach? If not, why not?

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  • $\begingroup$ The enumeration of the phenyl carbons is arbitrarily chosen to start at the functional group. If you are not talking about isotopically labeling a phenol molecule, then the enumeration will not change. $\endgroup$ Aug 31 '14 at 17:23
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    $\begingroup$ I guess by "meta-phenol" you mean a phenol that has another group besides the $\ce{OH}$ group attached in the meta position of the aromatic ring, right? $\endgroup$
    – Philipp
    Aug 31 '14 at 17:48
  • $\begingroup$ Are you interested in Gallic Acid? en.wikipedia.org/wiki/Gallic_acid $\endgroup$
    – LDC3
    Aug 31 '14 at 18:47
  • $\begingroup$ Related: Why does m-cresol exist, given that -OH group is activating and should be o-, p-directing? $\endgroup$
    – user7951
    Nov 6 '16 at 16:18
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The hydroxyl groups in phenols are ortho-/para-directing. So, if you want to introduce a group in the meta position with respect to a hydroxyl group you will have to "overwrite" the ortho-/para-preference. This can be done by starting out with meta-directing group which can later be transformed into $\ce{OH}$ in the position where the hydroxyl group shall be. Then you only need to introduce the group you want to be in the meta-position by a simple electrophilic aromatic substitution reaction and subsequently convert the meta-directing group into $\ce{OH}$.

An example for this procedure would be to start out with a carbonyl group at the position of the $\ce{OH}$ group, then nitrate the aromatic ring in the meta position and employ the Baeyer-Villiger oxidation to introduce a $\ce{OH}$ group:

enter image description here

Or you start out with a nitro group at the position of the $\ce{OH}$ group, then introduce chlorine in the meta position of the aromatic ring, reduce the nitro group to an amine, which is then coverted into an diazonium salt which in turn is then transformed into a $\ce{OH}$ group using a Schiemann-type reaction:

enter image description here

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