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Glyceric acid [HOCH2CH(OH)COOH]—the simplest sugar acid—represents a key molecule in biochemical processes vital for metabolism in living organisms such as glycolysis. Although critically linked to the origins of life and identified in carbonaceous meteorites with abundances comparable to amino acids, the underlying mechanisms of its formation have remained elusive. Here, we report the very first abiotic synthesis of racemic glyceric acid via the barrierless radical-radical reaction of the hydroxycarbonyl radical (HOĊO) with 1,2-dihydroxyethyl (HOĊHCH2OH) radical in low-temperature carbon dioxide (CO2) and ethylene glycol (HOCH2CH2OH) ices. Using isomer-selective vacuum ultraviolet photoionization reflectron time-of-flight mass spectrometry, glyceric acid was identified in the gas phase based on the adiabatic ionization energies and isotopic substitution studies. This work reveals the key reaction pathways for glyceric acid synthesis through nonequilibrium reactions from ubiquitous precursor molecules, advancing our fundamental knowledge of the formation pathways of key biorelevant organics—sugar acids—in deep space.
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Octyl Co-grafted PrSO 3 H/SBA-15: Tunable Hydrophobic Solid Acid Catalysts for Acetic Acid Esterification
- Award ID(s):
- 1560519
- PAR ID:
- 10302146
- Date Published:
- Journal Name:
- ChemCatChem
- Volume:
- 9
- Issue:
- 12
- ISSN:
- 1867-3880
- Page Range / eLocation ID:
- 2231 to 2238
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/cctc.201601370
