Structural elucidation of dioxa‐cage compounds from tetrahydroisobenzofuran‐1(3H)‐one: analysis of NMR data and GIAO chemical shifts calculations

• Autor(a) principal: Resende, Gabriela da Costa
• Data de Publicação: 2016
• Outros Autores: Alvarenga, Elson Santiago
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: https://doi.org/10.1002/mrc.4483; http://www.locus.ufv.br/handle/123456789/18824
• topic: NMR; 1H; 13C; NMR calculations; DFT-GIAO; Norbornene derivatives; Dioxa-cage compounds; Electrophilic addition

The polycyclic compounds, especially the dioxa-cages, have attracted considerable attention in recent years. In our work, a series of 9β-substituted 3-oxo-4,11-dioxatetracyclo[5.2.1.1 5,8 .0 2,6 ]undecane compounds were unexpectedly isolated during bromination, chlorination and epoxidation reactions of the 3-hydroxy-3a,4,7,7a-tetrahydro-4,7-methanoisobenzofuran-1(3H)-one. After careful analysis of the NMR data, the chemical shifts of the isolated and the expected products were predicted by theoretical calculations using density functional theory and gauge including atomic orbitals. The best correlation between calculated and experimental data was evaluated by comparing mean absolute errors and applying DP4 probability methodology. Results from both approaches indicated a correct structural elucidation.