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Abstract Herein, we developed the recyclable ligand‐free iridium (Ir)‐hydride based Ir0nanoparticles (NPs) for the first regioselective partial hydrogenation of PV‐substituted naphthalenes. Both the isolated and in situ generated NPs are catalytically active. A control nuclear magnetic resonance (NMR) study revealed the presence of metal‐surface‐bound hydrides, most likely formed from Ir0species. A control NMR study confirmed that hexafluoroisopropanol as a solvent was accountable for substrate activation via hydrogen bonding. High‐resolution transmission electron microscopy of the catalyst supports the formation of ultrasmall NPs, and X‐ray photoelectron spectroscopy confirmed the dominance of Ir0in the NPs. The catalytic activity of NPs is broad as showcased by highly regioselective aromatic ring reduction in various phosphine oxides or phosphonates. The study also showcased a novel pathway toward preparingbis(diphenylphosphino)‐5,5′,6,6′,7,7′,8,8′‐octahydro‐1,1′‐binaphthyl (H8‐BINAP) and its derivatives without losing enantioselectivity during catalytic events.
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Ligand control of regioselectivity in palladium-catalyzed heteroannulation reactions of 1,3-Dienes
Abstract Olefin carbofunctionalization reactions are indispensable tools for constructing diverse, functionalized scaffolds from simple starting materials. However, achieving precise control over regioselectivity in intermolecular reactions remains a formidable challenge. Here, we demonstrate that using PAd2nBu as a ligand enables regioselective heteroannulation ofo-bromoanilines with branched 1,3-dienes through ligand control. This approach provides regiodivergent access to 3-substituted indolines, showcasing excellent regioselectivity and reactivity across a range of functionalized substrates. To gain further insights into the origin of selectivity control, we employ a data-driven strategy, developing a linear regression model using calculated parameters for phosphorus ligands. This model identifies four key parameters governing regioselectivity in this transformation, paving the way for future methodology development. Additionally, density functional theory calculations elucidate key selectivity-determining transition structures along the reaction pathway, corroborating our experimental observations and establishing a solid foundation for future advancements in regioselective olefin difunctionalization reactions.
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- Award ID(s):
- 2238081
- PAR ID:
- 10581661
- Publisher / Repository:
- Nature
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 15
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1038/s41467-024-49803-y
