Question

Which of the following is a Gattermann reaction?

पर्याय

• \[\ce{ArN_2^+X- ->[CuCl/HCl] ArCl + N2 \uparrow}\]

• \[\ce{ArN_2^+X- ->[K1][\Delta] ArI + N2 \uparrow + KX}\]

• \[\ce{ArN^+_2X- ->[HBF4] ArN^+_2BF^-_4 -> ArF + N2 \uparrow BF3}\]

• \[\ce{ArN^+_2 X^- ->[Cu/HBr] ArBr + N2 \uparrow}\]

Answer 1

\[\ce{ArN^+_2 X^- ->[Cu/HBr] ArBr + N2 \uparrow}\]

Explanation:

Chlorine or bromine can be introduced into the arene ring in the Gattermann reaction by treating the arene diazonium salt solution with the appropriate halogen acid in the presence of copper powder.

\[\ce{AR - N^+_2X^- ->[Cu + HX][(X = Cl, Br)] Ar - X + N2}\]