orgo question

Started by issa
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issa

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can someone explain the answer to this question?
 

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here is what i am thinking... 3 double bonds gives us 6 pi orbitals and there is one orbital from N because N is located in the far right. so, there are 7. is this correct?
 
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In pyridine, the aromatic compound already has 6 pi electrons (also, it satisfies all the other criteria for aromaticity), so the lone pairs on nitrogen doesn't contribute to the compound, whereas in pyrrole, the lone pairs on nitrogen do contribute to give an aromatic sextet, b/c there are only 4 pi electrons .

hope this helps!
 
The answer is 6 because the lone pairs on N are in an sp3 hybirdized orbital tha is Ortagonal (90 degress ) to the pi system and is not contributing to the stablitly of the aromatic ring