Related Experiment Video
Updated: Jun 17, 2026

Developing Photosensitizer-Cobaloxime Hybrids for Solar-Driven H2 Production in Aqueous Aerobic Conditions
Published on: October 5, 2019
Light induced multiphase chemistry of gas-phase ozone on aqueous pyruvic and oxalic acids
I Grgić1, L I Nieto-Gligorovski, S Net
1Laboratory for Analytical Chemistry, National Institute of Chemistry, Hajdrihova 19, P.O. Box 660, SI-1001 Ljubljana, Slovenia.
Abstract:
In this study for the first time it has been shown that pyruvic acid can affect the atmospheric multiphase reactions of ozone with oxalic acid due to its properties as a photosensitizer. To this end, the photochemical batch multiphase reactions of a mixture of pyruvic acid/oxalic acid (PA/OA) and gas-phase ozone under simulated sunlight were studied as a function of time using high pressure liquid chromatography equipped with a UV detector (HPLC-UV) and electrospray ionization mass spectrometry (ESI-MS) to investigate product formation. Following the simultaneous ozone and light irradiation the first peak for pyruvic and oxalic acids (retention time = 3.68 min) decreased to 67% of the initial intensity after a 12 h reaction while a broad and not well defined peak appeared at longer retention times. After prolonged exposure times this broad peak shifted to shorter retention times: from 14 min at 2 h reaction to 8 min at 12 h. The HPLC-UV analysis of the reaction mixture simultaneously exposed to ozone and irradiated by simulated sunlight for 6-12 h revealed the presence of high weight molecular mass products and formation at longer times of highly non-polar products. The results obtained from ESI-MS have clearly demonstrated that the distribution of high molecular weight products is consistent with an oligomer system. No evidence of oligomer formation was found after the sample (PA/OA) was exposed only to either ozone or irradiated with UV/Vis light using the same instrumental conditions.
Related Concept Videos
Oxidative Cleavage of Alkenes: Ozonolysis
Ozone is a symmetrical bent molecule stabilized by a resonance structure.
Phase I Reactions: Oxidation of Carbon-Heteroatom and Miscellaneous Systems
In carbon-nitrogen systems, aliphatic and aromatic amines can undergo oxidative reactions. Secondary and tertiary amines, like those found in tricyclic antidepressants, can undergo N-dealkylation, a process that involves the oxidation of the alkyl group. In addition, oxidative...
Phase I Oxidative Reactions: Overview
Pyruvate Oxidation
First, the enzyme pyruvate dehydrogenase removes the carboxyl group from pyruvate and releases it as carbon dioxide. The stripped molecule is then oxidized and releases electrons, which are then picked up by NAD+...
Acid Halides to Carboxylic Acids: Hydrolysis
As shown below, the mechanism involves a nucleophilic attack by water at the carbonyl carbon to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen π bond along with the departure of a halide ion. A final proton transfer step yields carboxylic acid...
Phase I Reactions: Oxidation of Aliphatic and Aromatic Carbon-Containing Systems
Oxidation reactions are fundamental in aromatic carbon-containing systems. An example is the hydroxylation of phenobarbital, a process that transforms it into...

