Assessing Peroxygenase-Mediated Oxidations in the Presence of High Concentrations of Water-Miscible Co-Solvents

The use of water-miscible organic co-solvents in biocatalysis is a simple procedure for obtaining higher enzymatic activities toward hydrophobic substrates. However, effects on activity and stability have to be carefully evaluated, also with regard to the type and concentration of the respective co-solvent. In this contribution, we investigated...

Valorization of Small Alkanes by Biocatalytic Oxyfunctionalization

The oxidation of alkanes into valuable chemical products is a vital reaction in organic synthesis. This reaction, however, is challenging, owing to the inertness of C−H bonds. Transition metal catalysts for C−H functionalization are frequently explored. Despite chemical alternatives, nature has also evolved powerful oxidative enzymes (e. g.,...

Nuclear Waste and Biocatalysis: A Sustainable Liaison?

It is well-known that energy-rich radiation induces water splitting, eventually yielding hydrogen peroxide. Synthetic applications, however, are scarce and to the best of our knowledge, the combination of radioactivity with enzyme-catalysis has not been considered yet. Peroxygenases utilize H2O2 as an oxidant to promote highly selective...

Piezobiocatalysis: Ultrasound-Driven Enzymatic Oxyfunctionalization of C-H Bonds

Peroxygenases have long inspired the selective oxyfunctionalization of various aliphatic and aromatic compounds, because of their broad substrate spectrum and simplicity of catalytic mechanism. This study provides a proof-of-concept of piezobiocatalysis by demonstrating peroxygenase-catalyzed oxyfunctionalization reactions fueled by...

Expanding the Spectrum of Light-Driven Peroxygenase Reactions

Peroxygenases require a controlled supply of H₂O₂ to operate efficiently. Here, we propose a photocatalytic system for the reductive activation of ambient O₂ to produce H₂O₂ which uses the energy provided by visible light more efficiently based on the combination of wavelength...

Bias-Free in Situ H₂O₂ Generation in a Photovoltaic-Photoelectrochemical Tandem Cell for Biocatalytic Oxyfunctionalization

Peroxygenases catalyze selective oxyfunctionalization of hydrocarbons with high conversion efficiencies using H₂O₂ as a key cosubstrate. Here, we report an unbiased photoelectrochemical (PEC) tandem structure consisting of a FeOOH/BiVO₄ photoanode, a Cu(In,Ga)Se₂ solar absorber, and a graphitic...

Cascading g-C₃N₄ and Peroxygenases for Selective Oxyfunctionalization Reactions

Peroxygenases are very interesting catalysts for specific oxyfunctionalization chemistry. Instead of relying on complicated electron transport chains, they rely on simple hydrogen peroxide as the stoichiometric oxidant. Their poor robustness against H₂O₂ can be addressed via in situ generation of H₂O<sub>2<...

Selective Activation of C−H Bonds in a Cascade Process Combining Photochemistry and Biocatalysis

Selective oxyfunctionalizations of inert C−H bonds can be achieved under mild conditions by using peroxygenases. This approach, however, suffers from the poor robustness of these enzymes in the presence of hydrogen peroxide as the stoichiometric oxidant. Herein, we demonstrate that inorganic photocatalysts such as gold–titanium dioxide...

Photoelectroenzymatic Oxyfunctionalization on Flavin-Hybridized Carbon Nanotube Electrode Platform

Peroxygenases are very promising catalysts for oxyfunctionalization reactions. Their practical applicability, however, is hampered by their sensitivity against the oxidant (H₂O₂), therefore necessitating in situ generation of H₂O₂. Here, we report a photoelectrochemical approach to provide...

Selective Photooxidation Reactions using Water-Soluble Anthraquinone Photocatalysts

The aerobic organocatalytic oxidation of alcohols was achieved by using water-soluble sodium anthraquinone sulfonate. Under visible-light activation, this catalyst mediated the aerobic oxidation of alcohols to aldehydes and ketones. The photo-oxyfunctionalization of alkanes was also possible under these conditions.

The Oxygen Dilemma: A Severe Challenge for the Application of Monooxygenases?

Monooxygenases are promising catalysts because they in principle enable the organic chemist to perform highly selective oxyfunctionalisation reactions that are otherwise difficult to achieve. For this, monooxygenases require reducing equivalents, to allow reductive activation of molecular oxygen at the enzymes' active sites. However, these...