Detailed 1H and 13C NMR Spectral Data Assignment for Two Dihydrobenzofuran Neolignans

• Autor(a) principal: Medeiros,Talita C. T.
• Data de Publicação: 2016
• Outros Autores: Dias,Herbert J., Silva,Eliane O., Fukui,Murilo J., Soares,Ana Carolina F., Kar,Tapas, Heleno,Vladimir C. G., Donate,Paulo M., Parreira,Renato L. T., Crotti,Antônio E. M.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Journal of the Brazilian Chemical Society (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532016000100136
• topic: neolignans; oxidative coupling; J-resolved; benzofurans

In this work we present a complete proton (1H) and carbon 13 (13C) nuclear magnetic resonance (NMR) spectral analysis of two synthetic dihydrofuran neolignans (±)-trans-dehydrodicoumarate dimethyl ester and (±)-trans-dehydrodiferulate dimethyl ester. Unequivocal assignments were achieved by 1H NMR, proton decoupled 13C (13C{1H}) NMR spectra, gradient-selected correlation spectroscopy (gCOSY), J-resolved, gradient-selected heteronuclear multiple quantum coherence (gHMQC), gradient-selected heteronuclear multiple bond coherence (gHMBC) and nuclear Overhauser effect spectroscopy (NOESY) experiments. All hydrogen coupling constants were measured, clarifying all the hydrogen signals multiplicities. Computational methods were also used to simulate the 1H and 13C chemical shifts and showed good agreement with the trans configuration of the substituents at C7 and C8.