Aerobic Baeyer–Villiger Oxidation Catalyzed by a Flavin‐Containing Enzyme Mimic in Water

Abstract

Direct incorporation of molecular oxygen into small organic molecules has attracted mucha ttention for the development of new environmentally friendly oxidation processes. In line with this approach,b ioinspired systems mimicking enzyme activities are of particular interest since they may perform catalysis in aqueous media. Demonstrated herein is the incorporation of an atural flavin cofactor (FMN) into the specific microenvironment of aw ater-soluble polymer which allows the efficient reduction of the FMN by NADH in aqueous solution. Once reduced, this artificial flavoenzyme can then activate molecular dioxygen under aerobic conditions and result in the Baeyer-Villiger reaction at room temperature in water.

Aerobic oxidation catalyzed by polyoxometalates associated to an artificial reductase at room temperature and in water

“…This was not unexpected since the FMN, buried into the microenvironment of the PEI, had already been shown to be able to activate dioxygen to perform the Baeyer-Villiger oxidation. 64 The combination of Zn5W19, FMN and NADH gave a 40% yield in sulfoxide after 16 hours of reaction. The same result was also found for the FMN/PEIguan-oct/Zn5W19/NADH full system.…”

“…The proportion of guanidinium and octyl groups grafted to the polymer were determined by 1 H NMR after lyophilization of the aqueous solution. 64 Alternatively, the commercial multibranched 25 kDa PEI was also used for comparison with the modified one. Catalytic experiments were performed in tinted glass vials in order to avoid any photochemical side reaction with the photosensitive flavin cofactor.…”