Please use this identifier to cite or link to this item:
|Type:||Artigo de periódico|
|Title:||Conformational Preferences For N,n-dimethyl-2-haloacetamides (halo=f, Cl, Br And I) Through Theoretical And Experimental Studies: An Unexpected Orbital Interaction|
|Abstract:||Conformational preferences and orbital interactions of N,N-dimethyl-2- fluoroacetamide (1), N,N-dimethyl-2-chloroacetamide (2), N,N-dimethyl-2- bromoacetamide (3) and N,N-dimethyl-2-iodoacetamide (4) were analyzed using experimental infra-red data, theoretical calculations and NBO analysis. The conformational equilibria of compounds 1-4 can be represented by their cis and gauche rotamers. The gauche form of 1 is stable in the vapor phase and in a non-polar solvent, but the cis is predominant in a polar solvent. For 2-4 the gauche form is more stable than the cis, in both the vapor and liquid phases. These conformational preferences were attributed to the orbital interaction between two antibonding orbitals, π* C=O→σ*C-X. This unexpected interaction was possibly due to the high (0.3) electron density on π* C=O, which results from the interaction between one nitrogen lone pair and π*C=O. © 2005 Elsevier B.V. All rights reserved.|
|Appears in Collections:||Unicamp - Artigos e Outros Documentos|
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.