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Synthetic dioxygenase reactivity by pairing electrochemical oxygen reduction and water oxidation.

ABSTRACT: The reactivity of molecular oxygen is crucial to clean energy technologies and green chemical synthesis, but kinetic barriers complicate both applications. In synthesis, dioxygen should be able to undergo oxygen atom transfer to two organic molecules with perfect atom economy, but such reactivity is rare. Monooxygenase enzymes commonly reductively activate dioxygen by sacrificing one of the oxygen atoms to generate a more reactive oxidant. Here, we used a manganese-tetraphenylporphyrin catalyst to pair electrochemical oxygen reduction and water oxidation, generating a reactive manganese-oxo at both electrodes. This process supports dioxygen atom transfer to two thioether substrate molecules, generating two equivalents of sulfoxide with a single equivalent of dioxygen. This net dioxygenase reactivity consumes no electrons but uses electrochemical energy to overcome kinetic barriers.

SUBMITTER: Hoque MA

PROVIDER: S-EPMC10902909 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature

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Synthetic dioxygenase reactivity by pairing electrochemical oxygen reduction and water oxidation.

Hoque Md Asmaul MA Gerken James B JB Stahl Shannon S SS

Science (New York, N.Y.) 20240111 6679

The reactivity of molecular oxygen is crucial to clean energy technologies and green chemical synthesis, but kinetic barriers complicate both applications. In synthesis, dioxygen should be able to undergo oxygen atom transfer to two organic molecules with perfect atom economy, but such reactivity is rare. Monooxygenase enzymes commonly reductively activate dioxygen by sacrificing one of the oxygen atoms to generate a more reactive oxidant. Here, we used a manganese-tetraphenylporphyrin catalyst ...[more]

PMID: 38207052

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