✍ Scribed by Ludger Ernst; Victor Wray
No coin nor oath required. For personal study only.
📜 SIMILAR VOLUMES
The complete assignment of the 1H, 13C and 19F NMR spectra of eight Ñuoro-substituted 3H-naphthopyrans was achieved by the concerted application of homonuclear (1HÈ1H) and heteronuclear (13CÈ1H and 19FÈ1H) correlations.
## Abstract Analyses of the ^1^H, ^13^C and ^19^F NMR spectra of 15 mono‐, di‐, tri‐ or tetrafluoro‐substituted steroids were carried out by two‐dimensional ^1^H^1^H and ^1^H^13^C shift correlation experiments.
Two tagging reagents using a quinoxalinone Ñuorophore were synthesized and, for the Ðrst time, completely physicochemically characterized. The 1H and 13C spectra were entirely assigned using a combination of two-dimensional gradient enhanced HMQC, HMBC experiments and one-dimensional NOE di †erence
Indirect nuclear Overhauser enhancements through 19F have been determined for the three-spin systems 'H-I9F-'H and 1H-'9F-'3C by steady-state presaturation of the appropriate proton, and applied to the conformational analysis of 5-bromo-2-fluoro-4-nitroacetanilide. The 'H NOE difference spectra at 4