Protonation is a chemical reaction in which an acid donates a proton (hydrogen ion, H+) to a molecule, resulting in the formation of a new species known as a protonated molecule or a hydrogen ion species. In protonation, the acid molecule acts as a Lewis acid and accepts an electron pair from a Lewis base, which is the molecule that loses a proton. Protonation plays a crucial role in various chemical processes, including acid-base reactions, pH regulation, enzyme catalysis, and drug-receptor interactions, among others. The degree of protonation can be influenced by various factors, such as the strength of the acid, the concentration of the proton, and the presence of other species in the solution.
Deprotonation is the process of removing a proton (positive hydrogen ion) from a molecule, leading to the formation of a negatively charged species called an anion. This process involves the transfer of a proton from a molecule to a nucleophile, a species that can accept a proton, to form a new bond. Deprotonation is a fundamental reaction in many chemical processes, including acid-base reactions, organic synthesis, and biological reactions. The extent of deprotonation depends on the acidic strength of the molecule and the basicity of the nucleophile, as well as other factors such as the solvent and temperature.