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Jan
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Suggestion for a Synthesis of Paracetamol — plausible?

I have seen a number of different plausible syntheses for paracetamol but they suffer from problems such poor regioselectivity of aromatic substitution (usually when nitrating phenol getting a mixture of undesired orthoortho and desired parapara). However, is the following not a plausible synthesis?...

  1. Take aniline (I believe it's commercially available but can be synthesised from mononitration then reduction).
  2. React with acetic anhydride to make the amide — still ortho-, para- still o,p directingdirecting and mildly activating and the directing effects are not acid sensitive as in aniline.
  3. Do a friedel craftsFriedel–Crafts acylation with the an acyl chloride.
  4. React with hydrogen peroxide and sodium hydroxide to get paracetamol via a dakinDakin reaction.

Of course the acylation will suffer a little with regioselectivity issues but I feel like it will suffer less as the amide group is larger than a hydroxyl so favours parapara on steric grounds more strongly and is thus a better solution than nitration of phenol and subsequent reduction.

Nitration of Phenolphenol then reduction and reaction with acetic anhydride is the most common hit on google so I assume it's the most common method. But what's wrong with what I have suggested?

Synthesis of Paracetamol

I have seen a number of different plausible syntheses for paracetamol but they suffer from problems such poor regioselectivity of aromatic substitution (usually when nitrating phenol getting a mixture of undesired ortho and desired para). However, is the following not a plausible synthesis?...

  1. Take aniline (I believe it's commercially available but can be synthesised from mononitration then reduction).
  2. React with acetic anhydride to make the amide - still o,p directing and mildly activating and the directing effects are not acid sensitive as in aniline.
  3. Do a friedel crafts acylation with the an acyl chloride.
  4. React with hydrogen peroxide and sodium hydroxide to get paracetamol via a dakin reaction

Of course the acylation will suffer a little with regioselectivity issues but I feel like it will suffer less as the amide group is larger than a hydroxyl so favours para on steric grounds more strongly and is thus a better solution than nitration of phenol and subsequent reduction.

Nitration of Phenol then reduction and reaction with acetic anhydride is the most common hit on google so I assume it's the most common method. But what's wrong with what I have suggested?

Suggestion for a Synthesis of Paracetamol — plausible?

I have seen a number of different plausible syntheses for paracetamol but they suffer from problems such poor regioselectivity of aromatic substitution (usually when nitrating phenol getting a mixture of undesired ortho and desired para). However, is the following not a plausible synthesis?

  1. Take aniline (I believe it's commercially available but can be synthesised from mononitration then reduction).
  2. React with acetic anhydride to make the amide — still ortho-, para-directing and mildly activating and the directing effects are not acid sensitive as in aniline.
  3. Do a Friedel–Crafts acylation with the an acyl chloride.
  4. React with hydrogen peroxide and sodium hydroxide to get paracetamol via a Dakin reaction.

Of course the acylation will suffer a little with regioselectivity issues but I feel like it will suffer less as the amide group is larger than a hydroxyl so favours para on steric grounds more strongly and is thus a better solution than nitration of phenol and subsequent reduction.

Nitration of phenol then reduction and reaction with acetic anhydride is the most common hit on google so I assume it's the most common method. But what's wrong with what I have suggested?

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RobChem
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Synthesis of Paracetamol

I have seen a number of different plausible syntheses for paracetamol but they suffer from problems such poor regioselectivity of aromatic substitution (usually when nitrating phenol getting a mixture of undesired ortho and desired para). However, is the following not a plausible synthesis?...

  1. Take aniline (I believe it's commercially available but can be synthesised from mononitration then reduction).
  2. React with acetic anhydride to make the amide - still o,p directing and mildly activating and the directing effects are not acid sensitive as in aniline.
  3. Do a friedel crafts acylation with the an acyl chloride.
  4. React with hydrogen peroxide and sodium hydroxide to get paracetamol via a dakin reaction

Of course the acylation will suffer a little with regioselectivity issues but I feel like it will suffer less as the amide group is larger than a hydroxyl so favours para on steric grounds more strongly and is thus a better solution than nitration of phenol and subsequent reduction.

Nitration of Phenol then reduction and reaction with acetic anhydride is the most common hit on google so I assume it's the most common method. But what's wrong with what I have suggested?