MolSynapsequestion bank
MolSynapse / Question bank / Haloalkanes and Haloarenes / Reactions of aryl halides
JEE Advanced levelOne or more correct optionsDifficulty 3 of 3hx158

1-Chloro-2,4-dinitrobenzene reacts with sodium methoxide in methanol to give 2,4-dinitroanisole. Which statements are correct?

  1. AThe slow step is attack of on the carbon bearing giving an anionic sigma (Meisenheimer) complex
  2. BThe negative charge of the intermediate is delocalised onto the oxygen atoms of the ortho and para nitro groups
  3. C1-Chloro-3,5-dinitrobenzene would react at the same rate under identical conditions
  4. DThe reaction goes through a benzyne intermediate

Answer: A, B

This is addition-elimination (SNAr). The nucleophile adds to , and charge is delocalised onto the ortho and para groups; then is lost. No benzyne forms because the reagent is not a very strong base like . Nitro groups meta to cannot delocalise the charge by resonance, so the 3,5-dinitro isomer is far less reactive.
Practice Haloalkanes and Haloarenes More on Reactions of aryl halides

More questions on Reactions of aryl halides