Toluene is nitrated and the resulting product is reduced with tin and hydrochloric acid. The product so obtained is diazotised and then heated with cuprous bromide. The reaction mixture so formed contains
(A)mixture of o− and p− bromotoluenes✓ Correct
(B)mixture of o - and p -dibromobenzenes
(C)mixture of o - and p -bromoanilines
(D)mixture of 0 - and m-bromotoluenes
Answer: (A)
Solution
Nitrating toluene gives a mixture of ortho and para nitrotoluenes, since the methyl group directs ortho and para. Reduction with tin and hydrochloric acid turns the nitro groups into amino groups, giving ortho and para toluidine, and diazotisation then converts these to the corresponding diazonium salts. Warming the diazonium salts with cuprous bromide replaces the diazonium group by bromine in a Sandmeyer reaction, so the mixture finally contains ortho and para bromotoluenes.
JEE Main · 2008 · 27 Apr 2008 · Offline · Single correct option
