Question

Velocity of the `S_(N^(2))` reaction depends on the concentration of the substrate as well as te nucleophile.
The reaction is favoured by strong `Nu^(overset(..)(ө))`, and in the presence of polar aprotic solvent, optically active halides give walden inversion by `S_(N^(2))` mechanism. the presence of hetro group (atom as `beta-C` atom, unsaturation at `beta-C`, and `(-overset(O)overset(||)(C)-)` Allyl halides also give `S_(N^(2))` mechanism. EDG at ortho-and para-positions in benzyl halides favours `S_(N^(1))` mechanism, whereas EWG favours `S_(N^(2))` mechanism.
Q. Which of the following will give `S_(N^(2))` reaction

Select the correct answer
A. (I) and (II)
B. (I) and (III)
C. (I),(II), and (III)
D. All

Answer 1

Correct Answer - C
`(I)implies1^(@)RX,(II) implies1^(@)RX,(III)implies[-overset(O)overset(||)(C)-]` group at `alpha-C` atom, (IV)`implies`Neopentyl halide (does not undergo either `S_(N^(1)) ` or `S_(N^(2))`)