Theoretical and experimental study of the orientational oxygen lone-pair effect on 1J(13C-1H) in methoxy- and methylene-dioxybenzene compounds1 1 Part of a Ph.D. thesis (R.R.B.) to be presented at the University of Buenos Aires, Argentina.
The difference between the 1JC-H values for C-H bonds cis and trans to oxygen lone pairs for methylenedioxybenzene and veratrole was studied experimentally and theoretically. Experimentally, the coupled and decoupled 13C NMR spectra of nine methoxybenzene and methylenedioxybenzene derivatives, some...
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| Formato: | Capítulo de libro |
| Lenguaje: | Inglés |
| Publicado: |
1990
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| Acceso en línea: | Registro en Scopus DOI Handle Registro en la Biblioteca Digital |
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| Sumario: | The difference between the 1JC-H values for C-H bonds cis and trans to oxygen lone pairs for methylenedioxybenzene and veratrole was studied experimentally and theoretically. Experimentally, the coupled and decoupled 13C NMR spectra of nine methoxybenzene and methylenedioxybenzene derivatives, some of which were synthesized for this work, were obtained and a consistent empirical trend was found. Theoretically, the CLOPPA method was used and it was found that the oxygen lone pairs have an effect of spatial proximity on the C-H bond cis to the lone pairs, which is found to be the main cause of the difference in the 1JC-H values. © 1990. |
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| ISSN: | 01661280 |
| DOI: | 10.1016/0166-1280(90)80044-O |