Reactivity of Carbonyl compounds (Application of I Effect)

Application of I-Effect

III. Reactivity of Carbonyl compounds

Characteristic reaction of carbonyl compounds are Nucleophilic addition reaction [NAR]

>C=O  +  E^+δ—Nu^-δ  ---->

Mechanism:-

 Examples:-

*Formation of Cynohydrine is an example of  'NAR'.

*Reactivity towards NAR is directly proportional to positive charge on SP² C [Carbonyl compound   >C=O   ]

Reaction towards NAR  ∝  +ve charge on SP² C

Reactivity order towards NAR :-

CCl₃—C^{+ δ}H=O^{- δ}   >   C^{+ δ}H₂=O^{- δ}   >   CH₃—C^{+ δ}H=O^{- δ}   >   CH₃CH₂—C^{+ δ}H=O^{- δ}

-->More +ve charge on carbon atom

-->More reactive towards NAR

Question:-

Which of the following is most reactive towards   'NAR'   ?

Option:-

Answer :- 

 (d)

Explanation: 

 Minimum +I effect

So, More +ve charge on C-atom

So, More reactive.

Reactivity order  :- 
 d  >  c  >  b  >  a