Department Seminar

Upcoming Seminar

Chemistry of Singlet Oxygen: From Phenolic Antioxidants and Exotic Peroxides to Porphyrinic Metal-Organic Frameworks as Photocatalysts
Prof. Matthias Selke, CSU Los Angeles

November 4, 2026
4:00pm-5:00pm in HSCI-103

Singlet molecular oxygen (¹Δ_g) is a powerful electrophilic oxidant. It is a highly toxic and at the same time a useful tool for oxyfunctionalization of carbon-carbon double bonds. Biomolecules targeted by singlet oxygen include guanine as well as several amino acids. We will discuss reaction pathways and kinetics of singlet oxygen reactions with amino acids (tryptophan, methionine) as well as the complex interaction of singlet oxygen with some phenolic antioxidants, namely resveratrol and derivatives.

In the second part of the seminar, we will present recent advances at the interface of materials chemistry and singlet oxygen. Photocatalysts for singlet oxygen production are of interest as singlet oxygen can be considered a "green" oxidant derived from molecular O2. Quantum dotphotosensitizer hybrids have been used to photochemically produce singlet oxygen, but this may lead to self-quenching and degradation of the quantum dot surface. Porphyrinic metal-organic frameworks (MOFs) may be a much better alterative as photocatalysts. Our work includes studies of the singlet oxygen ene reaction, [4+2] cycloaddition of singlet oxygen and photooxidation of organic sulfides and arylphosphines catalyzed by MOFs. Interestingly, substrate selectivity is altered in photooxidation processes catalyzed by MOFs as compared to analogous reactions in homogeneous solution.

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