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The heteroleptic borane catalyst (C 6 F 5 ) 2 B(CH 2 CH 2 CH 2 )BPin is found to hydrosilylatively reduce amides under mild conditions. Simple tertiary amides can be reduced using Me 2 EtSiH, whereas tertiary benzamides required a more reactive secondary silane, Et 2 SiH 2 , for efficient reduction. The catalytic system described exhibits exceptional chemoselectivity in the reduction of oligoamides and tolerates functionalities which are prone to reduction under similar conditions.
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This content will become publicly available on February 1, 2026
Dicobalt-catalyzed N=N coupling reactions of tertiary alkyl azides to form azoalkanes
Azoalkanes can serve as radical precursors for various catalytic and stoichiometric C–C bond-forming reactions. However, their use in these processes is hampered by the complexity of their synthesis, which often requires multiple steps and strong oxidants. Here, we report a direct denitrogenative dimerization of tertiary alkyl azides to form azoalkanes. The reaction uses a dicobalt catalyst, which is uniquely effective in this transformation relative to analogous monocobalt catalysts and an isostructural dinickel catalyst. Critical to the N=N coupling reactivity is the formation of a dicobalt imido intermediate that is resistant to undergoing competing H-atom abstraction. The catalytic N=N coupling provides access to a broad scope of tertiary azoalkanes, and the resulting products can be used to form hindered C–C bonds between quaternary carbons.
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- Award ID(s):
- 2349801
- PAR ID:
- 10589744
- Publisher / Repository:
- Cell Press
- Date Published:
- Journal Name:
- Chem
- ISSN:
- 2451-9294
- Page Range / eLocation ID:
- 102437
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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