Use este identificador para citar ou linkar para este item: http://repositorio.ufla.br/jspui/handle/1/55471
Título: Iodine gauche effect induced by an intramolecular hydrogen bond
Palavras-chave: Electrical energy
Energy
Iodine
Molecular structure
Solvents
Data do documento: 19-Ago-2022
Editor: American Chemical Society (ACS)
Citação: MARTINS, F. A. et al. Iodine gauche effect induced by an intramolecular hydrogen bond. The Journal of Organic Chemistry, [S.l.], v. 87, p. 11625-11633, 2022.
Resumo: The gauche conformer in 1-X,2-Y-disubstituted ethanes, that is, the staggered orientation in which X and Y are in closer contact, is only favored for relatively small substituents that do not give rise to large X···Y steric repulsion. For more diffuse substituents, weakly attractive orbital interactions between antiperiplanar bonds (i.e., hyperconjugation) cannot overrule the repulsive forces between X and Y. Our quantum chemical analyses of the rotational isomerism of XCH2CH2Y (X = F, OH; Y = I) at ZORA-BP86-D3(BJ)/QZ4P reveal that indeed the anti conformer is generally favored due to a less destabilizing I···F and I···O–H steric repulsion. The only case when the gauche conformer is preferred is when the hydroxyl hydrogen is oriented toward the iodine atom in the 2-iodoethanol. This is because of the significantly stabilizing covalent component of the I···H–O intramolecular hydrogen bond. Therefore, we show that strong intramolecular interactions can overcome the steric repulsion between bulky substituents in 1,2-disubstituted ethanes and cause the gauche effect. Our quantum chemical computations have guided nuclear magnetic resonance experiments that confirm the increase in the gauche population as X goes from F to OH.
URI: https://pubs.acs.org/doi/10.1021/acs.joc.2c01258
http://repositorio.ufla.br/jspui/handle/1/55471
Aparece nas coleções:DQI - Artigos publicados em periódicos

Arquivos associados a este item:
Não existem arquivos associados a este item.


Os itens no repositório estão protegidos por copyright, com todos os direitos reservados, salvo quando é indicado o contrário.