Basicity of Arylamines Arylamines have a larger positive△G° for Alkylammonium ion,RNH3+ protonation and are Arylammonium ion,ArNHg+ therefore less basic △G°aikyl than alkylamines, △Gaw1 primarily because of Alkylamine,RNH2 resonance stabilization Resonance of the ground state stabilization Arylamine,ArNH2 Nitrogen lone-pair electron density is delocalized in the :NH2 NH3+ amine but the charge is localized in the corresponding ammonium ion Aniline Anilinium ion (delocalized electrons) (localized chargeArylamines have a larger positive DG° for protonation and are therefore less basic than alkylamines, primarily because of resonance stabilization of the ground state ▪ Nitrogen lone-pair electron density is delocalized in the amine but the charge is localized in the corresponding ammonium ion Basicity of Arylamines