Question

(I) m-nitrobromobenzene (II) 2,4,6-trinitrobromobenzene
(III) p-nitrobromobenzene (IV) 2,4-dinitrobromobenzene
The decreasing order of reactivity for given compounds towards $O{H}^{-}$ ions is:

• A. I > II > III > IV
• B. II > IV > III > I
• C. IV > II > III > I
• D. II > IV > I > III

Answer 1

The correct option is B II > IV > III > I

Greater the number of nitro group at ortho and para position to $-Br$ group, greater is the reactivity towards $O{H}^{-}$ ions due to stabilising of intermediate carbanion. (II) has three nitro groups and is most reactive. (I) has nitro group at meta position is the least reactive.