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Abstract C−H amination and amidation by catalytic nitrene transfer are well‐established and typically proceed via electrophilic attack of nitrenoid intermediates. In contrast, the insertion of (formal) terminal nitride ligands into C−H bonds is much less developed and catalytic nitrogen atom transfer remains unknown. We here report the synthesis of a formal terminal nitride complex of palladium. Photocrystallographic, magnetic, and computational characterization support the assignment as an authentic metallonitrene (Pd−N) with a diradical nitrogen ligand that is singly bonded to PdII. Despite the subvalent nitrene character, selective C−H insertion with aldehydes follows nucleophilic selectivity. Transamidation of the benzamide product is enabled by reaction with N3SiMe3. Based on these results, a photocatalytic protocol for aldehyde C−H trimethylsilylamidation was developed that exhibits inverted, nucleophilic selectivity as compared to typical nitrene transfer catalysis. This first example of catalytic C−H nitrogen atom transfer offers facile access to primary amides after deprotection.
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A Metal–Organic Framework with Exceptional Activity for C−H Bond Amination
Abstract The development of catalysts capable of fast, robust C−H bond amination under mild conditions is an unrealized goal despite substantial progress in the field of C−H activation in recent years. A Mn‐based metal–organic framework (CPF‐5) is described that promotes the direct amination of C−H bonds with exceptional activity. CPF‐5 is capable of functionalizing C−H bonds in an intermolecular fashion with unrivaled catalytic stability producing >105turnovers.
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- Award ID(s):
- 1661655
- PAR ID:
- 10048106
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 57
- Issue:
- 2
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 511-515
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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