Problem: For Multi-Step Synthesis of Benzocaine:1) Why don't we simply oxidize p-toluidine with KMnO4 to make p-aminobenzoic acid? Wouldn't that be a faster method? What unwanted reaction(s) may occur?2)The isolation of p-aminobenzoic acid is the trickiest step due to the formation of an amino compound. Why don't we do the esterification step prior to the deprotection step?

FREE Expert Solution

Multistep synthesis of benzocaine involves:

  1. Acylation of p-toluidine by acetic anydride (protects amino group)
  2. Oxidation of ring methyl group on p-acetotoluidide by KMnO4
  3. Hydrolysis (deprotection) of amino group by HCl to yield PABA (p-aminobenzoic acid)
  4. Fischer Esterification by ethanol to produce benzocaine
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Problem Details

For Multi-Step Synthesis of Benzocaine:

1) Why don't we simply oxidize p-toluidine with KMnO4 to make p-aminobenzoic acid? Wouldn't that be a faster method? What unwanted reaction(s) may occur?

2)The isolation of p-aminobenzoic acid is the trickiest step due to the formation of an amino compound. Why don't we do the esterification step prior to the deprotection step?

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