2013 |
Ormazabal-Toledo, R; Contreras, R; Tapia, R A; Campodonico, P R Specific Nucleophile-Electrophile Interactions in Nucleophilic Aromatic Substitutions Artículo de revista Organic & Biomolecular Chemistry, 11 (14), pp. 2302-2309, 2013, ISSN: 1477-0520. Resumen | Enlaces | BibTeX | Etiquetas: base binary catalysis, group, groups, leaving mechanism, mixtures, nitro ortho-para ratio, reactions, secondary-amines, snar solvent @article{RN167, title = {Specific Nucleophile-Electrophile Interactions in Nucleophilic Aromatic Substitutions}, author = { R. Ormazabal-Toledo and R. Contreras and R.A. Tapia and P.R. Campodonico}, url = {/brokenurl#<Go to ISI>://WOS:000316011300012}, doi = {10.1039/c3ob27450k}, issn = {1477-0520}, year = {2013}, date = {2013-01-01}, journal = {Organic & Biomolecular Chemistry}, volume = {11}, number = {14}, pages = {2302-2309}, abstract = {We herein report results obtained from an integrated experimental and theoretical study on aromatic nucleophilic substitution (SNAr) reactions of a series of amines towards 1-fluoro-2,4-dinitrobenzene in water. Specific nucleophile-electrophile interactions in the title reactions have been kinetically evaluated. The whole series undergoes SNAr reactions where the formation of the Meisenheimer complex is rate determining. Theoretical studies concerning specific interactions are discussed in detail. It is found that H-bonding effects along the intrinsic reaction coordinate profile promote the activation of both the electrophile and the nucleophile. Using these results, it is possible to establish a hierarchy of reactivity that is in agreement with the experimental data. Second order energy perturbation energy analysis highlights the strong interaction between the ortho-nitro group and the acidic hydrogen atom of the amine. The present study strongly suggests that any theoretical analysis must be performed at the activated transition state structure, because the static model developed around the reactant states hides most of the relevant specific interactions that characterize the aromatic substitution process.}, keywords = {base binary catalysis, group, groups, leaving mechanism, mixtures, nitro ortho-para ratio, reactions, secondary-amines, snar solvent}, pubstate = {published}, tppubtype = {article} } We herein report results obtained from an integrated experimental and theoretical study on aromatic nucleophilic substitution (SNAr) reactions of a series of amines towards 1-fluoro-2,4-dinitrobenzene in water. Specific nucleophile-electrophile interactions in the title reactions have been kinetically evaluated. The whole series undergoes SNAr reactions where the formation of the Meisenheimer complex is rate determining. Theoretical studies concerning specific interactions are discussed in detail. It is found that H-bonding effects along the intrinsic reaction coordinate profile promote the activation of both the electrophile and the nucleophile. Using these results, it is possible to establish a hierarchy of reactivity that is in agreement with the experimental data. Second order energy perturbation energy analysis highlights the strong interaction between the ortho-nitro group and the acidic hydrogen atom of the amine. The present study strongly suggests that any theoretical analysis must be performed at the activated transition state structure, because the static model developed around the reactant states hides most of the relevant specific interactions that characterize the aromatic substitution process. |
2013 |
Specific Nucleophile-Electrophile Interactions in Nucleophilic Aromatic Substitutions Artículo de revista Organic & Biomolecular Chemistry, 11 (14), pp. 2302-2309, 2013, ISSN: 1477-0520. |