Why furan 2-aldehyde undergoes cannizaro reaction but pyrrole 2-aldehyde does not-explain ?

KAKALI GHOSH November 02, 2018 1

Why furan 2-aldehyde undergoes cannizaro reaction but pyrrole 2-aldehyde does not-explain ?

Oxygen is more electronegative than nitrogen. consequently, the lone pair on 'O' atom is more tightly held.

So, it is less available for preserving the aromatic character of furan.

But, the lone pair of electron on 'N'atom is more available for preserving the aromatic character of pyrrole ring.

Now, the cannizaro reaction occurs by the nucleophilic attact.

Therefore, the approach of nucleophile towards the carbonyl carbon of furan becomes more facilites than pyrrole.

That is why furan 2-aldehyde undergoes cannizaro reaction,but pyrrole 2-aldehyde does not.