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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Experimental and theoretical evaluation of trans-3-halo-2-hydroxy-tetrahydropyran conformational preferences. Beyond anomeric interaction

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Author(s):
Barbosa, Thais M. [1] ; Viesser, Renan V. [1] ; Abraham, Raymond J. [2] ; Rittner, Roberto [1] ; Tormena, Claudio F. [1]
Total Authors: 5
Affiliation:
[1] Univ Estadual Campinas, UNICAMP, Inst Chem, BR-13083970 Campinas, SP - Brazil
[2] Univ Liverpool, Dept Chem, Liverpool L69 3BX, Merseyside - England
Total Affiliations: 2
Document type: Journal article
Source: RSC ADVANCES; v. 5, n. 45, p. 35412-35420, 2015.
Web of Science Citations: 6
Abstract

Conformational isomerism in trans-3-X-2-hydroxy-tetrahydropyrans (X = F, Cl, Br, I) was investigated by NMR spectroscopy and electronic structure calculations. The compounds were synthesized, purified and identified by H-1, C-13 and selective TOCSY NMR spectra and by HSQC, COSY and NOESY contour maps. The geometries and conformer energies for the most stable conformers in the isolated molecules were calculated using M06-2X hybrid functional (DFT) and MP2 (ab initio) methods with the aug-cc-pVTZ basis set. Theoretical calculations taking into account the solvent effect (CHCl3 and DMSO) were performed using the IEFPCM solvent model, M06-2X/aug-cc-pVTZ level of theory for C, H and O atoms and M06-2X/aug-cc-pVDZ-PP with pseudopotential for the iodine atom. NBO, QTAIM and NCI analyses were applied to identify which stereoelectronic interactions are responsible for their conformational preferences. The conformer stability changes in the presence of solvent. The anomeric effect does not appear to have a significant influence on the molecular conformations in these molecules. (AU)

FAPESP's process: 14/12776-6 - Development and application of NMR techniques to analyse complex mixtures
Grantee:Thaís Mendonça Barbosa
Support type: Scholarships in Brazil - Doctorate
FAPESP's process: 14/25903-6 - Molecular structure of some amino acids and dipeptides
Grantee:Roberto Rittner Neto
Support type: Regular Research Grants
FAPESP's process: 13/03477-2 - DOSY methods for analyses of the complex mixtures
Grantee:Claudio Francisco Tormena
Support type: Regular Research Grants