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The accurate detection, classification, and separation of chiral molecules are pivotal for advancing pharmaceutical and biomolecular innovations. Engineered chiral light presents a promising avenue to enhance the interaction between light and matter, offering a noninvasive, high-resolution, and cost-effective method for distinguishing enantiomers. Here, we present a nanostructured platform for surface-enhanced infrared absorption–induced vibrational circular dichroism (VCD) based on an achiral plasmonic system. This platform enables precise measurement, differentiation, and quantification of enantiomeric mixtures, including concentration and enantiomeric excess determination. Our experimental results exhibit a 13 orders of magnitude higher detection sensitivity for chiral enantiomers compared to conventional VCD spectroscopic techniques, accounting for respective path lengths and concentrations. The tunable spectral characteristics of this achiral plasmonic system facilitate the detection of a diverse range of chiral compounds. The platform’s simplicity, tunability, and exceptional sensitivity holds remarkable potential for enantiomer classification in drug design, pharmaceuticals, and biological applications.
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Enantioselective Synthesis of Enantioisotopomers with Quantitative Chiral Analysis by Chiral Tag Rotational Spectroscopy
Abstract Fundamental to the synthesis of enantioenriched chiral molecules is the ability to assign absolute configuration at each stereogenic center, and to determine the enantiomeric excess for each compound. While determination of enantiomeric excess and absolute configuration is often considered routine in many facets of asymmetric synthesis, the same determinations for enantioisotopomers remains a formidable challenge. Here, we report the first highly enantioselective metal‐catalyzed synthesis of enantioisotopomers that are chiral by virtue of deuterium substitution along with the first general spectroscopic technique for assignment of the absolute configuration and quantitative determination of the enantiomeric excess of isotopically chiral molecules. Chiral tag rotational spectroscopy uses noncovalent chiral derivatization, which eliminates the possibility of racemization during derivatization, to perform the chiral analysis without the need of reference samples of the enantioisotopomer.
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- Award ID(s):
- 1904686
- PAR ID:
- 10371124
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 61
- Issue:
- 33
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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