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Abstract Engineered heme protein biocatalysts provide an efficient and sustainable approach to develop amine‐containing compounds through C−H amination. A quantum chemical study to reveal the complete heme catalyzed intramolecular C−H amination pathway and protein axial ligand effect was reported, using reactions of an experimentally used arylsulfonylazide with hemes containing L=none, SH−, MeO−, and MeOH to simulate no axial ligand, negatively charged Cys and Ser ligands, and a neutral ligand for comparison. Nitrene formation was found as the overall rate‐determining step (RDS) and the catalyst with Ser ligand has the best reactivity, consistent with experimental reports. Both RDS and non‐RDS (nitrene transfer) transition states follow the barrier trend of MeO−−
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Enantioselective Addition of Pyrazoles to Dienes**
Abstract We report the first enantioselective addition of pyrazoles to 1,3‐dienes. Secondary and tertiary allylic pyrazoles can be generated with excellent regioselectivity. Mechanistic studies support a pathway distinct from previous hydroaminations: a Pd0‐catalyzed ligand‐to‐ligand hydrogen transfer (LLHT). This hydroamination tolerates a range of functional groups and advances the field of diene hydrofunctionalization.
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- Award ID(s):
- 1956457
- PAR ID:
- 10282891
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 60
- Issue:
- 36
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 19660-19664
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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