Producción Científica Profesorado

Three-center intramolecular hydrogen bonding in oxamide derivatives. NMR and X-ray diffraction study



Tlahuextl Romero, Angela Margarita

1998

F. J. Martínez-Martínez, I. I. Padilla-Martínez, M. A. Brito, E. D. Geniz, R. C. Rojas, J. B. R. Saavedra, H. Höpfl, Margarita Tlahuextl, R. Contreras, 12. Three-center intramolecular hidrogen bonding in oxamide derivatives. NMR and X-ray diffraction study, J. Chem. Soc. Perkin Trans. 2, 401-406 (1998). DOI: 10.1039/A704640E


Abstract


This contribution describes the synthesis and structural investigation of the symmetric and non-symmetric oxamides N,N?-bis(2-hydroxyphenyl)oxamide 1, N,N?-bis(5-tert-butyl-2-hydroxyphenyl)oxamide 2, N,N?-bis(3,5-dimethyl-2-hydroxyphenyl)oxamide 3, N,N?-bis(2-hydroxybenzyl)oxamide 4, N,N?-diphenethyloxamide 5, N-(2-hydroxyphenyl)-N?-(2-methoxyphenyl)oxamide 6, N-(2-hydroxyphenyl)-N?-phenethyloxamide 7, (1S,2R)-()-N-(2-hydroxyphenylcarbamoylcarbonyl)norephedrine 8, (1R,2S)-()-N-(2-hydroxyphenylcarbamoylcarbonyl) 9, ethyl N-(2-hydroxyphenyl)oxalamate 10 and ethyl N-(2-methoxyphenyl)oxalamate 11. The structures were established by 1H, 13C, 15N and variable temperature NMR spectroscopy. Compounds 14 and 611 are stabilized by intramolecular three-center hydrogen bonding between the amide proton and two oxygen atoms. The 1H NMR ??/?T value of the amide proton correlates with the 15N NMR chemical shift. The X-ray diffraction molecular structures of 1 and 11 showed a planar conformation with trans configuration in the solid state, corresponding to the preferred conformation found in solution.



Producto de Investigación




Artículos relacionados

Synthesis and structural studies of N-(p-toluenesulfonyl)-amino acid 3,5-di-tert-butyl-2-phenolamide...

Chlorination reactions of ephedrines revisited. Stereochemistry and functional groups effect on the ...

New 3,3?[2,2?-oxy-bis-(oxazaborolidine)]-ethylenes. Structural studies by NMR, X-ray, and quantum ch...

Hydrogen bond studies in substituted N-(2-hydroxyphenyl)--2-[(4-methylbenzenesulfonyl)amino]acetamid...

Synthesis and structural studies of new N-(p-toluenesulfonyl)amino acid o-phenolamides

Diastereoselective alkylation of chiral glycinate derivatives containing the a-phenylethyl group.

Hydrogen bond studies in substituted N-(2-hydroxyphenyl)--2-[(4-methylbenzenesulfonyl)amino]acetamid...

Synthesis and structural studies of new N-(p-toluenesulfonyl)amino acid o-phenolamides

Synthesis and structural studies of N-(p-toluenesulfonyl)-amino acid 3,5-di-tert-butyl-2-phenolamide...

Speciation of the new ligand di-isopropyliminodiacetoamide with Cu(II) using computational processin...