Affordable Access

Publisher Website

Acid-catalyzed nucleophilic additions to carbonyl groups: is the accepted mechanism the rule or an exception?

Authors
Type
Published Article
Journal
The Journal of Organic Chemistry
1520-6904
Publisher
American Chemical Society
Publication Date
Volume
78
Issue
6
Pages
2327–2335
Identifiers
DOI: 10.1021/jo302390r
PMID: 23419137
Source
Medline

Abstract

The transesterification reaction, and in particular the methanolysis of ethyl acetate with sulfuric acid as catalyst, is used as a model reaction to study the acid-catalyzed nucleophilic addition to a carbonyl group. Continuum solvation methods (SMD and IEF-PCM) and the MPWB1K functional are used. The reaction mechanism is studied in methanol and in acetonitrile as solvents. Our results indicate that the acid-catalyzed addition mechanism is stepwise, and the transition state (TS) is a contact ion-pair. The counteranion of the acid catalyst remains in the reaction site playing an important role in the TS of this reaction. Changes in the reaction kinetics and the ionic/nonionic nature of the TS with the ionizing ability of the solvent and the strength of the acid catalyst are explored. Additional calculations at the CBS-Q3 level of theory reinforce the conclusions of this paper. The results obtained allow the generalization of important ideas regarding the mechanism of the nucleophilic addition to carbonyl groups.

There are no comments yet on this publication. Be the first to share your thoughts.

Statistics

Seen <100 times
0 Comments