Total assignment of the 1H and 13C NMR spectra of phenanthro[9,10-b]thiophene: Concerted use of two-dimensional NMR techniques
โ Scribed by Milton D. Johnston Jr; Miguel Salazar; Larry D. Sims; Andrew S. Zektzer; Raymond N. Castle; Gary E. Martin
- Publisher
- John Wiley and Sons
- Year
- 1989
- Tongue
- English
- Weight
- 444 KB
- Volume
- 27
- Category
- Article
- ISSN
- 0749-1581
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โฆ Synopsis
The 'H and I3C NMR spectra of phenanthro(9,10-b]thiophene were totally assigned using a combination of twodimensional NMR techniques. Direct heteronuclear correlations were established using heteronuclear chemical shift correlation with semi-selective proton decoupling. Two methods were employed to establish the identity of vicinal neighboring protons: heteronuclear relayed coherence transfer and low-pass J-filtered heteronuclear relayed coherence transfer. The versatilities of the two techniques were compared. Quaternary carbon resonance assignments and the orientations of individual spin systems relative to one another were accomplished using the protondetected long-range heteronuclear multiple quantum coherence experiment (HMBC). Key long-range inter-ring proton homonuclear spin couplings served to confirm the orientations of the proton spin systems. KEY WORDS 2D NMR Heteronuclear chemical shift correlation Heteronuclear relayed coherence transfer Proton-detected long-range heteronuclear multiple quantum coherence HMBC Low-pass J-filtration 2 10
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