Reimer–Tiemann Reaction (Phenol + CHCl₃ + NaOH → Salicylaldehyde (ortho-CHO) + 3NaCl)
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Phenol + CHCl₃ + NaOH → Salicylaldehyde (ortho-CHO) + 3NaCl
What each symbol means
| Symbol | What it stands for |
|---|---|
| NaOH | Base — deprotonates phenol and generates :CCl₂ from CHCl₃ |
| :CCl₂ | Dichlorocarbene — electrophilic intermediate that attacks phenoxide ring |
| CHCl₃ | Chloroform — generates dichlorocarbene (:CCl₂) in situ |
When to use this
Requires aqueous NaOH and heating. The intermediate dichlorocarbene (:CCl₂) attacks the ortho position of phenoxide. If CCl₄ is used instead of CHCl₃, salicylic acid (–COOH) forms instead of aldehyde.