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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

On the Protonation and Deuteration of Hydroxy- Substituted Naphthalenes - A ¹H NMR Study

Hartmann, Horst, Yu, Xiuling 16 May 2024 (has links)
The ¹HNMR spectra of all possible structural isomers of mono and dihydroxy substituted naphthalenes are measured in trifluoracetic acid and trifluormethanesulfonic acid as well as in their deuterated derivatives. These spectra indicate different protonation/deuteration positions in the compounds studied. Whereas with the relative weak TFA the OH group as most basic group of the substrates is protonated, with the more acidic TFS also aromatic positions with lower basicity are protonated. However, some of these position were indicated only by using deutertated acids. To quantify the degree of proton/deuterium exchange at the aromatic rings, dioxane as proton standard was used. For the OH-protonation a complex between the appropriate naphthol and the acid used, in which a quick proton exchange can be occur, is assumed. Furthermore, the formation of corresponding trifluoroacetates or triflates by reaction of the naphthols with the corresponding acids has been indicated. In some cases, in which the ring positions of protonation are not definitely clear, 2D NOESYNMR experiments have been performed.

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