## Abstract The ^13^C n.m.r. spectra of 36 naturally occurring xanthones are reported and all chemical shifts assigned. The shifts in substituted xanthones can be predicted from substituent effects evaluated for simple derivatives. The agreement between calculated and observed shifts decreases as t
Carbon-13 n.m.r. studies of methylquinolines and methylisoquinolines
✍ Scribed by Ja-An Su; Ernest Siew; Ellis V. Brown; Stanford L. Smith
- Publisher
- John Wiley and Sons
- Year
- 1977
- Tongue
- English
- Weight
- 370 KB
- Volume
- 10
- Category
- Article
- ISSN
- 0749-1581
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
Spectra are reported for all seven methylquinolines, nine dimethylquinolines, six methylisoquinolines and one dimethylisoquinoline. Substituent effects for the α, ortho, meta, para, vinylogous para and peri positions are reported for the monomethylcompounds. Additivity of these substituent effects is demonstrated for the dimethyl compounds which also exhibit a vicinal dimethyl steric effect.
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