When -2,3- dibromobutane reacts with potassium hydroxide, some of the products are (2S,3R)-3 bromobutan-2-ol and its enantiomer and trans-2-bromobut-2-ene.Give mechanisms to account for these products.
Solution 57 SP:
Here, we are going to propose the mechanisms to account for these products.
The reaction is as follows:
SN2(second order Nucleophilic substitution reaction) reaction with inversion occur. SN2 reaction requires attack by a nucleophile on the back side of an electrophilic carbon atom. Therefore , in the product, the nucleophile assumes a stereochemical position opposite the position the leaving group originally occupied.This is called an inversion of configuration at the carbon atom.
Thus, backside attack inverts the configuration of the carbon atom.
If the reaction undergoes SN1 mechanism, it would form the same racemic mixture. If a nucleophile attacks the carbocation from the front side , the product molecule shows retention of configuration, whereas when it attacks from the back side gives a product molecule showing inversion of configuration. Racemization is simply a combination of retention and inversion. But in the above reaction, it does not occur.