Aldehydes Ketones Question 15
Question: The order of decreasing ease of reaction with ammonia is
Options:
A) anhydrides, esters, ethers
B) anhydrides, ethers, esters
C) ethers, anhydrides, esters
D) esters, ethers, anhydrides
Show Answer
Answer:
Correct Answer: A
Solution:
[a] 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 $ \underset{Amide}{\mathop{R-\overset{O}{\mathop{\overset{||}{\mathop{C}}}}-NH_2}}<\underset{Ester}{\mathop{R-\overset{O}{\mathop{\overset{||}{\mathop{C}}}}-OR}}< $
$ \underset{Acidanhydride}{\mathop{R-\overset{O}{\mathop{\overset{||}{\mathop{C}}}}-OCOCH_3}}<\underset{Acidchloride}{\mathop{R-\overset{O}{\mathop{\overset{||}{\mathop{C}}}}-Cl}} $
BETA
