NMR Spectra for Carbonyl Compounds
المؤلف:
..................
المصدر:
LibreTexts Project
الجزء والصفحة:
.................
13-10-2019
1957
NMR Spectra for Carbonyl Compounds
Hydrogens attached to carbon adjacent to the sp2 hybridized carbon in aldehydes and ketones usually show up 2.0-2.5 ppm.
. 
Aldehyde hydrogens are highly deshielded and appear far downfield as 9-10 ppm.
Chemical shift of each protons is predicted by 1H chemical shift ranges (Ha): chemical shift of methyl groups (1.1 ppm). (Hb) The chemical shift of the -CH- group move downfield due to effect an adjacent aldehyde group: (2.4 ppm). The chemical shift of aldehyde hydrogen is highly deshielded (9.6 ppm).
4) Splitting pattern is determined by (N+1) rule: Ha is split into two peaks by Hb(#of proton=1). Hb has the septet pattern by Ha (#of proton=6). Hc has one peak.(Note that Hc has doublet pattern by Hb due to vicinal proton-proton coupling.)
الاكثر قراءة في التشخيص العضوي
اخر الاخبار
اخبار العتبة العباسية المقدسة
