Quaternary Charge-Transfer Complex Enables Photoenzymatic Intermolecular Hydroalkylation of Olefins
Claire G Page1, Simon J Cooper1, Jacob S DeHovitz1
1Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States.
Journal of the American Chemical Society
|December 28, 2020
Summary
This study introduces photoenzymatic hydroalkylation using flavin-dependent enzymes to form C-C bonds. It achieves enantioenriched amide synthesis through a novel enzyme-templated radical mechanism.
Area of Science:
- Biocatalysis
- Organic Chemistry
- Photochemistry
Background:
- Intermolecular carbon-carbon bond-forming reactions are crucial but underdeveloped in biocatalysis.
- Flavin-dependent enzymes offer potential for novel catalytic transformations.
Purpose of the Study:
- To develop a photoenzymatic intermolecular hydroalkylation of olefins.
- To explore novel radical initiation mechanisms in biocatalysis.
- To synthesize enantioenriched γ-stereogenic amides.
Main Methods:
- Utilizing flavin-dependent 'ene'-reductases for catalysis.
- Employing photoexcitation of enzyme-templated charge-transfer complexes for radical initiation.
- Controlling radical terminating hydrogen atom transfer within the enzyme active site.
Main Results:
- Demonstrated photoenzymatic intermolecular hydroalkylation of olefins.
- Established a unique radical initiation mechanism involving a charge-transfer complex.
- Achieved synthesis of enantioenriched γ-stereogenic amides.
Conclusions:
- Photoenzymatic catalysis can enable new biocatalytic transformations.
- Novel electron transfer mechanisms can drive radical formation in enzymes.
- Flavin-dependent enzymes are versatile catalysts for C-C bond formation.
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