| Texto completo | |
| Autor(es): |
Oliveira, Paulo R. de
;
Rittner, Roberto
;
Guerrero, Palimecio G.
;
Batista, Patrick R.
;
Costa, Gustavo J.
Número total de Autores: 5
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Química Nova; v. 46, n. 8, p. 7-pg., 2023-05-12. |
| Resumo | |
Textbooks show that in cis-1,3-disubstituted cyclohexane molecule, the conformer with the substituents in the diaxial positions is higher in energy and hence, it presents a low population in the conformational equilibrium. The diaxial conformer is destabilized by the repulsion between the substituent groups and the axial hydrogen atoms on the same side of the ring. This interaction is known as the 1,3-diaxial interaction. In this study, the solvent effect on the conformational equilibria of cis-3-N-ethylaminocyclohexanol (cis-3-EACOL) and cis-3-N,N-diethylaminocyclohexanol (cis-3-DEACOL) has been assessed through the spin-spin coupling constant (3JHH). The results show that the diaxial conformation of cis-3-EACOL decreases from 92% in CCl4 ( increment Gee-aa = 1.48 kcal mol-1) to 10% in DMSO-d6 ( increment Gee-aa = -1.31 kcal mol-1). For cis-3-DEACOL the diaxial conformer decreased from 36% in CCl4 ( increment Gee-aa= -0.33 kcal mol-1) to 7% in Pyridine -d5 ( increment Gee-aa = -1.55 kcal mol-1). The stabilization of the diaxial conformer in nonpolar solvents takes place due to the O-H center dot center dot center dot N intramolecular hydrogen bond, which overcomes the 1,3-diaxial steric interactions. (AU) | |
| Processo FAPESP: | 21/09687-5 - Avaliação de preferências conformacionais de moléculas fluoradas e estudo do caminho de transmissão do acoplamento JFH utilizando dinâmica molecular de Car-Parrinello |
| Beneficiário: | Patrick Rodrigues Batista |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |