Question

Why the metal prefer to bind from pyridine nitrogen instead of amino nitrogen?

Answer 1

Answer:

Pyridine is a weaker base than saturated amines of similar structure because its electron pair is in an sp2-hybridized orbital, and the electron pair is more tightly held by the atom. Protonation of a similar nitrogen atom in pyrimidine is more favorable because the charge is delocalized to the second nitrogen atom

Answer 2

Heya!!

The basicity of amines of different classes do not follow a simple pattern because the number of groups bonded to nitrogen affects the electron density at the nitrogen atom.

And, the stability of the conjugate acid in the solvent has a major affect on basicity. Thus, the basicity of amines can be explained only for amines with similar structures at the nitrogen atoms.

Thanks!