Answer to Question #94071 in Organic Chemistry for Megha Nautiyal

Question

In SN2 mechanism inversion of configuration takes place. Explain.

Answer 1

Since in case of SN2 mechanism the nucleophile attacks from backside and the leaving group leaves from he front side the configuration is reversed.

Backside attack is preffered as compared to front side because nucleophile has a lone pair of electrons to be shared with the electrophilic center, and the leaving group is going to take a lone pair of electrons with it upon leaving. Because like charges repel each other, the nucleophile will always proceed by a backside displacement mechanism