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,Ndimethyl-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 I 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, pi*(C=O)->sigma*(C-X). This unexpected interaction was possibly due to the high (0.3) electron density on pi*C=O, which results from the interaction between one nitrogen lone pair and pi*C -> O. (c) 2005 Elsevier B.V. All rights reserved.|
|Editor:||Elsevier Science Bv|
|Appears in Collections:||Artigos e Materiais de Revistas Científicas - Unicamp|
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.