title: Mechanism of acid-catalyzed hydrolysis of formamide from cluster-continuum model calculations: concerted versus stepwise pathway.
abstract: The acid-catalyzed hydrolysis of formamide in aqueous solutions was investigated by ab initio calculations. Solvent effects on the hydrolysis reaction were reasonably considered by the cluster-continuum model with explicit water molecules in the first solvation shell, and the selection of hydration cluster plays an important role in reliable estimation of thermodynamic values for the hydrolysis reaction. Possible concerted and stepwise mechanisms of the O-protonated and N-protonated pathways were investigated by extensive calculations. On the basis of unbiased theoretical treatments on all plausible pathways, the O-protonated stepwise pathway was shown to be the favored mechanism, and the predicted activation free energies for the rate-determining step and the breaking of the C-N bond are 21.8 and 9.4 kcal/mol by B3LYP, respectively. The present results show good agreement with experiment and provide a complete description of the acid-catalyzed hydrolysis of formamide.
authors.affiliation: Department of Chemistry and State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 360015, China.
authors.forename: Binju
authors.initials: B
authors.lastname: Wang
authors.forename: Zexing
authors.initials: Z
authors.lastname: Cao
mesh_terms: D000143:Acids / Q000737:chemistry*; D002384:Catalysis; D005559:Formamides / Q000737:chemistry*; D006868:Hydrolysis; D056004:Molecular Dynamics Simulation; D015394:Molecular Structure; D011522:Protons; D011789:Quantum Theory; D013816:Thermodynamics; D014867:Water / Q000737:chemistry
chemical_list: D000143:Acids; D005559:Formamides; D011522:Protons; D014867:Water; C031066:formamide