MCQ
Reaction of phenol with chloroform/sodium hydroxide to give $o$-hydroxy benzaldehyde involves the formation of
  • Dichloro carbene
  • B
    Trichloro carbene
  • C
    Chlorine atoms
  • D
    Chlorine molecules

Answer

Correct option: A.
Dichloro carbene
a
(a)This is Reimer-Tiemann reaction where the electrophile is dichlorocarbene $(:CC{l_2})$ generated from chloroform by the action of a base.


$O{H^ - } + CHC{l_3}$ $HOH + :CCl_2^ - \to C{l^ - } + :CC{l_2}$

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