Proton transfer can occur via several pathways, including concerted, stepwise, or through relay mechanisms. In a concerted mechanism, the proton transfer happens simultaneously with other bond-making or bond-breaking events. In a stepwise mechanism, the proton transfer occurs in discrete steps. Relay mechanisms involve intermediate species that temporarily accept and donate the proton, facilitating the overall transfer. The nature of the proton transfer mechanism can significantly affect the reaction kinetics and thermodynamics.
