Theoretical study on the proton transfer reactions within phenol-base complexes

Abstract

In neutral phenol-base complexes, the most stable conformation contains a hydrogen-bonding between hydroxyl hydrogen atom of phenol and heteroatom of interacting base. Ionization enhances the acidity of phenol, and the proton transfer between phenol and base moiety becomes more favorable. The extent of proton transfer is crucially dependent upon the nature of base. In phenol-ammonia complex ion, the completely proton transferred complex ion is formed without activation barrier. Proton transfer reaction is improbable within ionic phenol-water complex. In ionic phenol-methanol complex the proton transfer is reversible and depends on the excess energy of ionic complex. The dessociation energy barrier is also an important factor in producing dissociated proton transferred product.