Related Experiment Video
Updated: Jan 6, 2026

Qualitative Identification of Carboxylic Acids, Boronic Acids, and Amines Using Cruciform Fluorophores
Published on: August 19, 2013
Detection and Chiral Recognition of α-Hydroxyl Acid through 1 H and CEST NMR Spectroscopy Using a Ytterbium
Haonan He1,2, Kelu Zhao1,2, Long Xiao3
1State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, P. R. China.
Abstract:
Chiral α-hydroxyl acids are of great importance in chemical synthesis. Current methods for recognizing their chirality by 1 H NMR are limited by their small chemical shift differences and intrinsic solubility problem in organic solvents. Herein, we developed three YbDO3A(ala)3 derivatives to recognize four different commercially available chiral α-hydroxyl acids in aqueous solution through 1 H NMR and chemical exchange saturation transfer (CEST) spectroscopy. The shift difference between chiral α-hydroxyl acid observed by proton and CEST NMR ranged from 15-40 and 20-40 ppm, respectively. Our work demonstrates for first time, that even one chiral center on the side-arm chain of cyclen could set the stage for rotation of the other two non-chiral side chains into a preferred position. This is ascribed to the lower energy state of the structure. The results show that chiral YbDO3A-like complexes can be used to discriminate chiral α-hydroxyl acids with a distinct signal difference.
More Related Videos
10:52Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
12:47Nuclear Magnetic Resonance Spectroscopy for the Identification of Multiple Phosphorylations of Intrinsically Disordered Proteins
Published on: December 27, 2016
Related Concept Videos
¹H NMR Chemical Shift Equivalence: Enantiotopic and Diastereotopic Protons
In chiral compounds such as 2-butanol, replacing the methylene hydrogens at C3 produces a pair of...
NMR Spectroscopy and Mass Spectrometry of Aldehydes and Ketones
NMR and Mass Spectroscopy of Carboxylic Acids
While α protons of carboxylic acids absorb at 2–2.5 ppm, β protons absorb further upfield.
Carboxylic acids are easily identified by dissolving them in deuterium oxide, which results in a rapid exchange of the acidic protons with deuterium. This leads to the...
Proton (¹H) NMR: Chemical Shift
Absorption signals of all the protium nuclei...
¹H NMR of Conformationally Flexible Molecules: Variable-Temperature NMR
Spectroscopy of Carboxylic Acid Derivatives