Give the equations of reactions for the preparation of: (any three)(a) Phenol from chlorobenzene (b) Salicyaldehyde from phenol (c) 2-Methoxyacetophenone from anisole
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- Phenol preparation via Wurtz-Fittig reaction involves nucleophilic substitution and hydrolysis.
- Salicyaldehyde is obtained by the haloform reaction, a method of introducing an aldehyde group.
- Acetylation of anisole forms 2-methoxyacetophenone through electrophilic substitution with acetyl chloride.
- Nitration of phenol using conc. HNO\(_3\) introduces nitro groups and leads to picric acid.
(a) The Wurtz-Fittig reaction is used here. Chlorobenzene (C\(_6\)H\(_5\)Cl) undergoes nucleophilic substitution with NaOH under high temperature and pressure (623K, 300 atm), followed by acidic hydrolysis, to form phenol.
(b) Salicyaldehyde from phenol
(b)
Phenol (C\(_6\)H\(_5\)OH) undergoes haloform reaction with CHCl\(_3\) and NaOH to produce salicylic acid intermediate, which then undergoes acid hydrolysis to yield salicyaldehyde.
(c)
Anisole (C\(_6\)H\(_5\)OCH\(_3\)) reacts with acetyl chloride (CH\(_3\)COCl) in the presence of anhydrous AlCl\(_3\) to form 2-methoxyacetophenone.
(d) Picric acid from phenol
Phenol is nitrated with concentrated nitric acid (HNO\(_3\)) to produce picric acid (2,4,6-trinitrophenol).
