question_answer

Which one of the following species will be most reactive in S^ 2 reaction?

A)                 

B)  

C)                        

D)    

Correct Answer: A

Solution :

                 \[{{S}_{N}}\] 2 reaction is a concerted bimolecular nucleophilic substitution that takes place by backside attack of a nucleophile and leads to a substitution product with inverted configuration at the substituted carbon. So, will be favoured at least sterically hindered carbon atom, ie, .