why Pyrrole is more basic than pyridine?
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Normally a sp2-nitrogen centre is less basic than a sp3-nitrogen centre due to the fact that sp2-centres are more electronegative than sp3-centres. But the case of pyrrole and pyridine is quite different. In pyridine, we can simply say that nitrogen is sp2 hybridised but in case of pyrrole it seems to be a sp3- centre but it's not, in fact it's also a sp2-centre ,the reason for this is that the lone pair of N in pyrrole is in conjugation with the 2 double bonds in the ring and making the ring aromatic. Now, as both N are sp2, we can simply compare basicity by observing the electronic effects only and as lone pair of N in pyrrole is in resonance so this lone pair can't be donated wheareas the lonepair of N in pyridine is localised and hence ready for donation. Hence, pyridine is more basic than
Hope it works..!
Normally a sp2-nitrogen centre is less basic than a sp3-nitrogen centre due to the fact that sp2-centres are more electronegative than sp3-centres. But the case of pyrrole and pyridine is quite different. In pyridine, we can simply say that nitrogen is sp2 hybridised but in case of pyrrole it seems to be a sp3- centre but it's not, in fact it's also a sp2-centre ,the reason for this is that the lone pair of N in pyrrole is in conjugation with the 2 double bonds in the ring and making the ring aromatic. Now, as both N are sp2, we can simply compare basicity by observing the electronic effects only and as lone pair of N in pyrrole is in resonance so this lone pair can't be donated wheareas the lonepair of N in pyridine is localised and hence ready for donation. Hence, pyridine is more basic than
Hope it works..!
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