ISSN: 2161-0401
+44 1478 350008
Silvana C Caglieri
Centro de Investigacion y Transferencia en Ingenieria Quimica Ambiental-Universidad Tecnologica Nacional, Argentina
Posters & Accepted Abstracts: Organic Chem Curr Res
A theoretical study of acetylation of ethanol catalyzed by Mn2+ ions from the analysis of intermediate of the reaction was carried out. The study of acetylation of alcohols is of great interest by the utility of its products of reaction and is one of the most frequently used transformations in organic synthesis as it provides an efficient means for protecting hydroxyl groups in a synthetic process. Acetylation of alcohols is a nucleophilic substitution reaction. This reaction can be catalyzed by Lewis acid, metallic ion. In reaction mechanism, the metallic ion formed a complex with the oxygen of the acetic anhydride carbonyl, facilitating the polarization of the same and the successive addition of alcohol at the position to form a tetrahedral intermediate, determining step of the rate of the reaction. Experimental studies were carried out and agreed that this reaction takes place with the formation of a tetrahedral intermediate. In the present theoretical work we investigated the structure and energy of the tetrahedral intermediate of the reaction catalyzed by Mn2+ ions. Geometries of all species involved in the acetylation were made and identified. All of the geometry optimizations were performed by the method at the DFT/B3LYP level of theory and were adopted the 6-31+G* basis sets. Energies were calculated using the Mechanics-UFF method. Following the same procedure it was identified the geometric parameters and energy of reaction intermediate. The calculations show 65.39 kcal/mol of energy for the tetrahedral intermediate and the energy of activation for the reaction was 26.29 kcal/mol.