There is evidence of catalytic formation of peroxide and ozone products via reactions between some amino acids and singlet oxygen in the presence of water. The initial process of the oxidation mechanism involves the amino acid and surrounding reactive singlet oxygen reacting to yield an endoperoxide at a chiral carbon. From these foundations we propose two possible mechanisms for the oxidation of water in the presence of the mentioned endoperoxide. The first mechanism we explore oxidizes water to hydrogen peroxide and leaves an alcohol group on the amino acid, while the second mechanism yields the original amino acid and trioxidane, which promptly degrades to form hydrogen peroxide. Employing density functional calculations to investigate the reactant, product, and transition state energetics, we characterize the potential energy surface of these two independent mechanisms for amino acids histidine and tryptophan. Additionally, the mechanism has been explored experimentally by studying the decomposition of tryptophan hydroperoxide intermediates. Tert-butylindole was synthesized using the Fischer Indole Synthesis. Upon the addition of oxalyl chloride, ammonia, and subsequent reduction, t-butyl tryptamine was synthesized in good yields. Protection of the free amine using acetic anhydride resulted in formation of N-acetyl-t-butyl-tryptamine. Singlet-oxygen mediated oxidation afforded the tryptophan hydroperoxide, and decomposition studies are currently under investigation. The energetics for the two catalytic pathways provide insight into water oxidation reactions via common organic molecules.<br/>

Oxidation of water catalyzed via natural and synthetic organic species

251st National Meeting (2016)

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