Why Are Amidines So Basic?

Since we can draw more significant resonance structures for the amidine case, the protonated amidine is more stable than the protonated amide. This difference in protonated product stabilities explains why amidines are more basic than amides.

Why Amidines are more basic than amines?

Amidines can be thought of as carboxylic acid derivatives with the carbonyl oxygen replaced by a nitrogen and hydrogen atom; amidines exhibit conjugation. Amidines are more basic (less acidic) than amines and amides by a factor of around 103 and 1012, respectively (from pKas).

Are Amidines basic?

Amidines are much more basic than amides and are among the strongest uncharged/unionized bases. Protonation occurs at the sp² hybridized nitrogen. This occurs because the positive charge can be delocalized onto both nitrogen atoms.