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Abstract A nickel‐catalyzed regiodivergent hydroarylation and hydroalkenylation of unactivated alkenyl carboxylic acids is reported, whereby the ligand environment around the metal center dictates the regiochemical outcome. Markovnikov hydrofunctionalization products are obtained under mild ligand‐free conditions, with up to 99 % yield and >20:1 selectivity. Alternatively, anti‐Markovnikov products can be accessed with a novel 4,4‐disubstituted Pyrox ligand in excellent yield and >20:1 selectivity. Both electronic and steric effects on the ligand contribute to the high yield and selectivity. Mechanistic studies suggest a change in the turnover‐limiting and selectivity‐determining step induced by the optimal ligand. DFT calculations reveal that in the anti‐Markovnikov pathway, repulsion between the ligand and the alkyl group is minimized (by virtue of it being 1° versus 2°) in the rate‐ and regioselectivity‐determining transmetalation transition state.
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This content will become publicly available on June 12, 2026
Multifunctional Chiral Silanol Ligands for Enantioselective Catalysis
We report transition metal catalysis using novel chiral metal-chelating ligands featuring a silanol coordinating group and peptide-like aminoamide scaffold. The catalytic properties of the silanol ligand are demonstrated through an enantioselective Cu-catalyzed N–H insertion affording unnatural amino acid derivatives in high selectivity. Our investigations into the silanol coordination mode include DFT calculations, ligand structure investigations, and X-ray structure analyses, which support the formation of an H-bond stabilized silanol-chelating copper carbenoid complex. A p–p stacking interaction revealed by DFT calculations is proposed to enable selectivity for aryl diazoacetate substrates, overcoming some of the traditional limitations of using these substrates.
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- Award ID(s):
- 2400351
- PAR ID:
- 10609981
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Chemical Science
- ISSN:
- 2041-6520
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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