Question
The order of decreasing ease of reaction with ammonia is
A.
anhydrides, esters, ethers
B.
anhydrides, ethers, esters
C.
ethers, anhydrides, esters
D.
esters, ethers, anhydrides
Answer :
anhydrides, esters, ethers
Solution :
Weaker the base, better the leaving group and hence more is the reactivity of the compound. The relative basic character of the four groups is \[NH_{2}^{-}>O{{R}^{-}}>OCOCH_{3}^{-}>C{{l}^{-}}\]
Thus the relative leaving ability of the four groups is $$NH_2^ - < O{R^ - } < OCOCH_3^ - < C{l^ - }$$
Hence the relative reactivity of the four acyl derivatives toward nucleophile is
Weaker the base, better the leaving group and hence more is the reactivity of the compound. The relative basic character of the four groups is \[NH_{2}^{-}>O{{R}^{-}}>OCOCH_{3}^{-}>C{{l}^{-}}\]
Thus the relative leaving ability of the four groups is $$NH_2^ - < O{R^ - } < OCOCH_3^ - < C{l^ - }$$
Hence the relative reactivity of the four acyl derivatives toward nucleophile is