Ultraviolet–visible phototransformation of dehydroacetic acid – Structural characterization of photoproducts and global ecotoxicity

Abstract

With the exception of one photoproduct, the structures proposed for the photoproducts on the basis of mass spectral interpretation have not been reported in previous studies. All photoproducts, with the exception of dimers, were detected after irradiation in the cosmetic emulsion. This result shows that personal care products containing DHA must be protected from direct sunlight to prevent photodegradation.

Photolysis, tautomerism and conformational analysis of dehydroacetic acid and a comparison with 2-hydroxyacetophenone and 2-acetyl-1,3-cyclohexanodione

“…On the other hand, De Vaugelade et al , [ 32 ] performed the photochemical degradation of 1 with a Xenon arc lamp using a natural light filter (for a realistic reproduction of the solar spectrum). They detected four photoproducts in the ACN solution after irradiation, two of them identified as dimers coming from its own [2+2]-cycloaddition ( Scheme 2 ), and relative amounts estimated by integrating the chromatographic peaks on the GC/MS.…”

“…[ 30 ] and De Vaugelade et al. [ 32 ], a [2+2]-cyclodimerization of 1 is a probable light promoted first step at wavelengths lower than 300 nm. With the exception of these recent works, there are, to the best of our knowledge, no previous mechanistic studies on the photoreaction of 1 under UV-light (254 nm).…”

Characterization of photoproducts and global ecotoxicity of chlorphenesin: A preservative used in skin care products

“…To avoid this degradation, packaging can be a particularly good protective element against UV radiations. Stability tests with this kind of degradation by Q‐sun test chamber study are also the key in order to anticipate the photodegradation and to ensure the role of the active compounds throughout it use [14‐17].…”