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Abstract Enantioselective, intermolecular alkene arylamination was achieved through gold redox catalysis. Screening of ligands revealed chiral P,N ligands as the optimal choice, giving alkene aminoarylation with good yields (up to 80 %) and excellent stereoselectivity (up to 99 : 1er). As the first example of enantioselective gold redox catalysis, this work confirmed the feasibility of applying a chiral ligand at the gold(I) stage, with the stereodetermining step (SDS) at the gold(III) intermediate, thus opening up a new way to conduct gold redox catalysis with stereochemistry control.
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Engineering Dirhodium Artificial Metalloenzymes for Diazo Coupling Cascade Reactions**
Abstract Artificial metalloenzymes (ArMs) are commonly used to control the stereoselectivity of catalytic reactions, but controlling chemoselectivity remains challenging. In this study, we engineer a dirhodium ArM to catalyze diazo cross‐coupling to form an alkene that, in a one‐pot cascade reaction, is reduced to an alkane with high enantioselectivity (typically >99 %ee) by an alkene reductase. The numerous protein and small molecule components required for the cascade reaction had minimal effect on ArM catalysis. Directed evolution of the ArM led to improved yields andE/Zselectivities for a variety of substrates, which translated to cascade reaction yields. MD simulations of ArM variants were used to understand the structural role of the cofactor on ArM conformational dynamics. These results highlight the ability of ArMs to control both catalyst stereoselectivity and chemoselectivity to enable reactions in complex media that would otherwise lead to undesired side reactions.
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- Award ID(s):
- 1700982
- PAR ID:
- 10288640
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 60
- Issue:
- 44
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 23672-23677
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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