Unravelling the Keto–Enol Tautomer Dependent Photochemistry and Degradation Pathways of the Protonated UVA Filter Avobenzone
Jacob A. Berenbeim, Natalie G. K. Wong, Martin C. R. Cockett, Giel Berden, Jos Oomens, Anouk M. Rijs, Caroline E. H. Dessent
Abstract
146 and 177 also appearing prominently. Analysis of the production spectra of these photofragments reveals that that strong enol to keto photoisomerism is occurring, and that protonation significantly disrupts the stability of the enol (UVA active) tautomer. Close comparison of fragment ion yields with the TD-DFT-calculated absorption spectra give detailed information on the location and identity of the dissociative excited state surfaces, and thus provide new insight into the photodegradation pathways of avobenzone, and photoisomerization of the wider class of β-diketone containing molecules.
Topics & Concepts
TautomerChemistryEnolProtonationPhotochemistryInfrared multiphoton dissociationPhotodegradationKeto–enol tautomerismDissociation (chemistry)PhotoisomerizationAbsorption spectroscopyIntramolecular forceExcited stateInfrared spectroscopyIonIsomerizationPhysical chemistryStereochemistryOrganic chemistryCatalysisAtomic physicsPhotocatalysisPhysicsQuantum mechanicsMass Spectrometry Techniques and ApplicationsPhotochemistry and Electron Transfer StudiesInnovative Microfluidic and Catalytic Techniques Innovation