Question

Walden inversion includes:

• A. SN1
• B. SN2
• C. Both SN1 and SN2
• D. Elimination

Hint:

In SN2 reactions, the backside attack by the nucleophile causes Walden inversion — key for chirality-based GPAT questions!

Answer 1

The Correct Option is B

- Walden inversion refers to the inversion of configuration (chirality) that occurs during a nucleophilic substitution reaction.
- This phenomenon is characteristic of SN2 bimolecular nucleophilic substitution reactions, where the nucleophile attacks the carbon from the side opposite to the leaving group.
- As a result, the spatial arrangement of atoms around the chiral center gets inverted — this is what we call a Walden inversion.
- SN1 reactions proceed through a planar carbocation intermediate and often lead to racemization rather than inversion.
- Elimination reactions (E1 or E2) do not involve inversion of configuration, as they lead to the formation of alkenes.
- Therefore, only SN2 reactions exhibit Walden inversion.