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Updated: Jun 22, 2026

Light-driven Enzymatic Decarboxylation
Published on: May 22, 2016
Photochemistry and thermal decarboxylation of alpha-phosphoryloxy-p-nitrophenylacetates
John E T Corrie1, V Ranjit N Munasinghe, Maria Rudbeck
1MRC National Institute for Medical Research, London, UK.
Abstract:
Alpha-carboxy-4-nitrobenzyl phosphate 4 and its derived monomethyl phosphate ester 5 were synthesized and purified by anion-exchange chromatography. A gradient of LiCl was necessary for elution of the anion-exchange column to avoid unexpected thermal decarboxylation that occurred during vacuum evaporation when the volatile triethylammonium bicarbonate buffer was used. Photolysis of each compound was accompanied by decarboxylation, and 4 released inorganic phosphate with near-100% stoichiometry. Time-resolved infrared spectroscopy of the photolysis reaction, coupled with density functional theory calculations of vibrational frequencies, enabled us to infer a mechanism for the photolytic pathway, although there was some evidence for a second pathway also being operative. In contrast to the results for 4, photolysis of 5 appeared to release little or no monomethyl phosphate.
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