%0 Journal Article
%T 17O NMR of Enamino-Diesters: Intramolecular Hydrogen Bonding in 5-Alkylaminomethylene-2,2-dimethyl-1,3-dioxane-4,6-diones
%A Jin-Cong Zhuo
%J Molecules
%D 1997
%I MDPI AG
%R 10.3390/feb97p1
%X Natural abundance 17O NMR spectra of a series of 5-alkylaminomethylene-2,2-dimethyl-1,3-dioxane-4,6-diones, recorded in acetonitrile solution, are reported. The ¦Ä(17O) values correlate well with those of 4-alkylaminobut-3-en-2-ones and with the pKa values of amines. The effects of the N-alkyl groups on the 17O shift values is diminished, owing to the resonance effects of the alkoxy groups. The shift difference (D¦ÄHB) between the two carbonyl groups is mainly attributed to the intramolecular hydrogen bonding and depends on the donor property of the amino group.
%K NMR
%K 17O NMR
%K enamino-diesters
%K intramolecular hydrogen bonding
%U http://www.mdpi.com/1420-3049/2/2/31