Question 37 of 39intermediate🧠 RememberShort Answer4 marks

Write equations of the following reactions: (i) Friedel-Crafts reaction – alkylation of anisole. (ii) Nitration of anisole. (iii) Bromination of anisole in ethanoic acid medium. (iv) Friedel-Craft's acetylation of anisole.

(i)
Answer

Anisole + CH₃Cl →(Anhyd. AlCl₃) 2-Methoxy-toluene (Minor) + 4-Methoxy-toluene (Major)

(ii)
Answer

Anisole + conc. HNO₃ + conc. H₂SO₄ → 2-Nitroanisole (Minor) + 4-Nitroanisole (Major)

(iii)
Answer

Anisole + Br₂ →(Ethanoic acid) p-Bromoanisole (Major) + o-Bromoanisole (Minor)

(iv)
Answer

Anisole + CH₃COCl →(Anhyd. AlCl₃) 2-Methoxy-acetophenone (Minor) + 4-Methoxy-acetophenone (Major)

Explanation

The textbook explains that the methoxy group (-OCH₃) in anisole is ortho, para-directing and activates the benzene ring towards electrophilic substitution. In all four reactions, the electrophile attacks at ortho and para positions, with para being the major product. For Friedel-Crafts reactions, anhydrous AlCl₃ acts as a Lewis acid catalyst. For bromination, the reaction proceeds even without FeBr₃ catalyst due to ring activation, yielding 90% para product.

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