Reimer-Tiemann reaction introduces an aldehyde group, on to the aromatic ring of phenol, ortho to the hydroxyl group. This reaction involves electrophilic aromatic substitution. This is a general method for the synthesis of substituted salicyladehydes as depicted below.
The electrophile in this reaction is
The electrophile in this reaction is
- (A): CHCl
- (B)
- (C)✓ Correct
- (D)
Answer: (C)
Solution
In the Reimer-Tiemann reaction, chloroform reacts with strong base to form the trichloromethyl anion, which then loses a chloride ion to generate dichlorocarbene :CCl₂. This neutral species with a divalent carbon atom (having only six electrons in its valence shell) is electron-deficient and acts as the electrophile that attacks the electron-rich aromatic ring of phenoxide ion.
JEE Advanced · 2007 · 08 Apr 2007 · Paper 2 · Single correct option