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Vibrational energy dynamics of glycine, N-methylacetamide, and benzoate anion in aqueous (D2O) solution

Ying Fang1, Shinsuke Shigeto, Nak-Hyun Seong

  • 1School of Chemical Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.

The Journal of Physical Chemistry. A
|December 11, 2008
PubMed

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In proton NMR spectroscopy, primary amines and secondary amines showcase their N–H protons as a broad signal in the chemical shift range between δ 0.5 and 5 ppm. The exact position in this range depends on several factors, including sample concentration, hydrogen bonding, and the type of solvent used. Since amine protons undergo fast proton exchange in solution, the protons are labile and therefore do not participate in any splitting with adjacent protons. Thus, the observed peak is broad and...
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Carboxylic acid derivatives contain an acyl group attached to a heteroatom such as chlorine, oxygen, or nitrogen. The carbonyl carbon and oxygen are both sp2-hybridized with an unhybridized p orbital.
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