Q. Decreasing order of reactivity in Williamson ether synthesis of the following is
(I) ,
(II) ,
(III) ,
(IV)

 2197  218 Delhi UMET/DPMTDelhi UMET/DPMT 2010 Report Error

Solution:

Williamsons ether synthesis involves pathway, ie, involves formation of transition state and back side attack.
Thus, less hindered alkyl halides react readily in Williamsons synthesis.
The order of hindrance is Allyl halide As the size of halide ion increases, reactivity towards reaction increases.
Thus, bromides are more reactive than their corresponding chlorides towards Williamsons ether synthesis.
Hence, the decreasing order of reactivity towards Williamsons ether synthesis is