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Transition-metal-catalyzed nitrene transfer is a convenient method to introduce nitrogen into simple substrates through either alkene aziridination or C–H bond amination. Silver complexes have an unusual capability to accommodate a broad range of N-donor ligands and coordination geometries in catalysts competent for nitrene transfer. This behavior has resulted in the ability to achieve tunable chemoselectivity between aziridination and C–H bond amidation, as well as tunable site-selective functionalization between two different C–H bonds. In this paper, efforts to engage the diversity of silver and rhodium catalysts to accomplish selective and tunable aziridination of mixtures of alkenes are discussed. It was found that the selectivity of dinuclear Rh catalysts is dictated largely by steric effects, while the identity of the ligand on silver can be tuned to influence whether the steric or electronic features in the competing alkenes is the primary factor controlling which precursor is preferentially aziridinated.
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Taming Nitrene Reactivity with Silver Catalysts
Nitrene transfer (NT) is a convenient strategy to directly transform C–H bonds into more valuable C–N bonds and exciting advances have been made to improve selectivity. Our work in silver-based NT has shown the unique ability of this metal to enable tunable chemo-, site-, and stereoselective reactions using simple N-dentate ligand scaffolds. Manipulation of the coordination environment and noncovalent interactions around the silver center furnish unprecedented catalyst control in selective NT and provide insights for further improvements in the field. 1 Introduction 1.1 Strategies for Nitrene Transfer 1.2 Brief Summary of Chemocatalyzed Nitrene Transfer 1.3 Focus of this Account 2 Challenges in Chemocatalyzed Nitrene Transfer 2.1 Reactivity Challenges 2.2 Selectivity Challenges 2.3 Chemoselective Nitrene Transfer 2.4 Site-Selective Nitrene Transfer 2.5 Enantioselective Nitrene Transfer 3 Summary and Perspective 3.1 Future Opportunities and Challenges 3.2 Conclusion
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- Award ID(s):
- 1954325
- PAR ID:
- 10227773
- Date Published:
- Journal Name:
- Synlett
- Volume:
- 32
- Issue:
- 01
- ISSN:
- 0936-5214
- Page Range / eLocation ID:
- 30 to 44
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1055/s-0040-1707197
