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Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: Zensation on June 02, 2014, 04:15:22 PM

Title: Is the Nitrogen in a Pyrimidine ring electron donating or withdrawing?
Post by: Zensation on June 02, 2014, 04:15:22 PM

Sort of confused here. I am inclined to think it is electron withdrawing since the pKa is so low, but I've never really understood how Nitrogen or NH on a ring can be electron withdrawing. Aren't amines typically nucleophilic? Does the absense of 1 or more hydrogen increase the electrophilicity? 

Title: Re: Is the Nitrogen in a Pyrimidine ring electron donating or withdrawing?
Post by: Hunter2 on June 03, 2014, 09:02:04 AM

It is donating. It is not part of the aromatic system. Difference to Pyrrol, where it is part fhe aromatic system.