Keras
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Aryl halides to phenols
Folks,
aryl sulphonates can be transformed to aryl phenols using alkaline fusion at 250 °C. Can the same be done from aryl halides, producing phenol(ate)
and sodium/potassium salts?
If not, what would be the best way to go from aryl halide to phenol?
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chempyre235
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The reaction you're describing is the Dow Process.
https://en.wikipedia.org/wiki/Dow_process_(phenol)
I found some other syntheses of phenol and derivatives here.
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clearly_not_atara
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For substitutions of aryl halides (except fluorides) the first thing to consider is always some kind of copper catalyst. Only bother thinking about
other options if that isn't possible for some reason.
For the hydrolysis of aryl sulfonates I am pretty sure that nucleophilic attack actually happens at sulfur rather than carbon but you may find a
radiolabelling study that proves me wrong. So in this case there is no catalyst.
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Keras
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Thanks to both.
Copper oxide with excess of copper (II) nitrate works for diazonium salts → phenol, but what would you suggest for halides?
The idea here is a fancy way to m-cresol. Toluene → p-nitrosotoluene → p-toluidine → p-toluidide → 3-bromo-4-toluidide → 3-bromo-4-toluidine
→ m-bromotoluene → m-cresol.
Vogel details a way to ‘deaminate’ an aryl compound using diazotisation followed by some sort of reaction involving copper (0) powder that can be
conveniently made by reducing copper (II) sulphate with ascorbic acid.
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DraconicAcid
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I was always taught that Grignards will react with dry oxygen to give oxides that hydrolyze to alcohols, but I'm not sure it's synthetically useful.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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Niklas
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Reaction of Grignard reagents with a source of hypochlorite may be a more synthetically viable version of this.
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Keras
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Quote: Originally posted by Niklas  | | Reaction of Grignard reagents with a source of hypochlorite may be a more synthetically viable version of this. |
Finding a dry source of hypo halides might be somewhat difficult?
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Niklas
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Calcium hypochlorite could work, no?
Chlorite may potentially also work, sodium chlorite is easily available because of its use for MMS.
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clearly_not_atara
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| Quote: Originally posted by Keras | Thanks to both.
Copper oxide with excess of copper (II) nitrate works for diazonium salts → phenol, but what would you suggest for halides? |
https://pubs.acs.org/doi/abs/10.1021/jo400702z
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Keras
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Thanks!
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