Theoretical study on the reaction mechanism of proton transfer in alaninamide

We present detailed theoretical studies of the proton transfer in the isolated alaninamide and the effect of hydratation on the transition state structures corresponding to the proton transfer from the keto form to enol form, employing the B3LYP/6-311++G(d,p) level. The barrier heights for H2O-assisted reactions are significantly lower than that of the gas phase tautomerization reaction from alaninamide to alaninamidic acid, implying the importance of the catalytic effect of H2O. (c) 2007 Elsevier B.V. All rights reserved.