Assertion : S_ N^2 reactions always proceed with inversion of con… - Vidyadip

MCQ

Assertion : ${S_{{N^2}}}$ reactions always proceed with inversion of configuration.
Reason : ${S_{{N^2}}}$ reaction of an optically active aryl halide with an aqueous solution of $KOH$ always gives an alcohol with opposite sign of rotation.

A
If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
B
If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
✓
If the Assertion is correct but Reason is incorrect.
D
If both the Assertion and Reason are incorrect.

✓

Answer

Correct option: C.

If the Assertion is correct but Reason is incorrect.

c
Assertion is true, because aryl halides do not undergo nucleophilic substitution under ordinary conditions. This is due to resonance, because of which the carbon-halogen bond acquires partial double bond character, hence, it becomes shorter and stronger and thus, cannot be replaced by nucleophiles. However, Reason is false

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