Theoretical study of HOCl-catalyzed keto-enol tautomerization of β-cyclopentanedione in an explicit water environment.

ABSTRACT: The mechanism of acid-catalyzed keto-enol tautomerization of β-cyclopentanedione (CPD) in solution is studied computationally. Reaction profiles are first calculated for a limited solvation environment using ab initio and density functional methods. Barrier heights for systems including up to one hydration shell of explicit water molecules depend strongly on the number of waters involved in proton transfer and to a lesser but significant extent on the number of waters forming hydrogen bonds with waters in the proton-transfer chain (each such water reduces the barrier by 4.4 kcal/mol on average). Barriers of 8-13 kcal/mol were obtained when a full or nearly full hydration shell was present, consistent with calculations for nonacid-catalyzed keto-enol tautomerization of related molecules. Th

SUBMITTER: D'Cunha C 

PROVIDER: S-EPMC3809839 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature