- Friday, June 13, 1986
- Benzo[b]phenanthro[4,3-d]thiophene: Spectral Assignment by Two-Dimensional NMR Methods and Tertiary Structure Determination
- Published at:Not Found
Two-dimensional heteronuclear chemical shift correlation, heteronuclear relayed coherence transfer and autocorrelated 13C--13C double quantum coherence have been used to assign the proton and 13C NMR spectra of benzo[b]phenanthro[4,3-d]thiophene. The highly complementary nature of the heteronuclear relay and carbon-carbon double quantum spectra conveniently provides the means of avoiding breaks in the carbon-carbon connectivity network assembled by the latter, which may arise when strongly AB rather than AX carbon-carbon pairings are encountered. Nuclear Overhauser difference spectra have shown the title compound to possess a tertiary helical structure similar to that of phenanthro[3,4-b]thiophene; the average separation between the H-1 and H-13 atoms of the title compound was found to be 2.06 ± 0.04 Å.