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Photochemical and thermal stability of some dihydroxyacetophenones used as UV-MALDI-MS matrices. | LitMetric

Photochemical and thermal stability of some dihydroxyacetophenones used as UV-MALDI-MS matrices.

Photochem Photobiol

CIHIDECAR-CONICET, Departamento de Quimica Organica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Buenos Aires, Argentina.

Published: June 2015

AI Article Synopsis

Article Abstract

2,4-, 2,5-, 2,6- and 3,5-dihydroxyacetophenone (DHA) used as matrices in matrix-assisted ultraviolet laser desorption/ionization mass spectrometry (UV-MALDI-MS) were studied by steady-state and transient absorption spectroscopy, together with DFT calculations at the B3LYP level of theory. All compounds have low fluorescence quantum yields, possibly due to an efficient excited-state intramolecular proton transfer (ESIPT). Laser flash photolysis (LFP) results showed that, only for 2,4-DHA, a phototautomer could be detected at λ = 400 nm. Their photochemical stability in solution at different wavelengths and conditions was analyzed by UV-Vis and (1)H nuclear magnetic resonance spectroscopy ((1)H-NMR), together with thin layer chromatography and ultraviolet laser desorption/ionization mass spectrometry (UV-LDI-MS). Only 3,5-DHA showed decomposition when irradiated, probably because phototautomerization is not possible. Thermal stability studies of these compounds in solid state were also conducted.

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Source
http://dx.doi.org/10.1111/php.12130DOI Listing

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