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Although chelation-assisted C–H olefination has been intensely investigated, Pd( ii )-catalyzed C–H olefination reactions are largely restricted to acrylates and styrenes. Here we report a quinoline-derived ligand that enables the Pd( ii )-catalyzed olefination of the C(sp 2 )–H bond with simple aliphatic alkenes using a weakly coordinating monodentate amide auxiliary. Oxygen is used as the terminal oxidant with catalytic copper as the co-oxidant. A variety of functional groups in the aliphatic alkenes are tolerated. Upon hydrogenation, the ortho -alkylated product can be accessed. The utility of this reaction is also demonstrated by the late-stage diversification of drug molecules.
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Ir( iii )-catalyzed ortho C–H alkylations of (hetero)aromatic aldehydes using alkyl boron reagents
Transition-metal-catalyzed C–H alkylation reactions directed by aldehydes or ketones have been largely restricted to electronically activated alkenes. Herein, we report a general protocol for the Ir( iii )-catalyzed ortho C–H alkylations of (hetero)aromatic aldehydes using alkyl boron reagents as the coupling partner. Featuring aniline as an inexpensive catalytic ligand, the method was compatible with a wide variety of benzaldehydes, heterocyclic aldehydes, potassium alkyltrifluoroborates as well as a few α,β-unsaturated aldehydes. An X-ray crystal structure of a benzaldehyde ortho C–H iridation intermediate was also successfully obtained.
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- Award ID(s):
- 1700982
- PAR ID:
- 10094687
- Date Published:
- Journal Name:
- Chemical Science
- Volume:
- 9
- Issue:
- 48
- ISSN:
- 2041-6520
- Page Range / eLocation ID:
- 8951 to 8956
- 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/10.1039/C8SC03606C
