Which among the following compounds will undergo fastest $\mathrm{S}_{\mathrm{N}} 2$ reaction.

JEE Main · 2024 · 08 Apr 2024 · Shift 1 · Haloalkanes and Haloarenes

Which among the following compounds will undergo fastest

S_{N} 2

reaction.

(A)(see structure)
(B)(see structure)
(C)(see structure)
✓ Correct
(D)(see structure)

Answer: (C)

Solution

_{N}

2 rate falls with steric hindrance at the reacting carbon: primary > secondary > neopentyl-type. The substrate in option (3) has the C–Br on an unhindered primary carbon (–CH

_{2}

Br), so it reacts fastest. Option (3).

JEE Main · 2024 · 08 Apr 2024 · Shift 1 · Single correct option

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