Binaphthyl Scaffold: A Class of Versatile Structure in Asymmetric C–H Functionalization

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(15), P. 9359 - 9396

Published: July 18, 2022

Over the past decades, transition metal-catalyzed enantioselective C–H functionalization has emerged as a straightforward and powerful tool for rapid access to chiral molecules. The enormous advances achieved in this emerging area largely rely on development of ligands that can enable both high levels enantiocontrol efficiency. Chiral bearing binaphthyl scaffolds have been proven be versatile asymmetric due their availability, unique stereochemical features, ease fine-tuning steric electronic properties. In Review, we summarized advance applications basis scaffold functionalization.

Language: Английский

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C–H functionalization with alkenes, allenes, and alkynes by half-sandwich rare-earth catalysts

Tetrahedron, Journal Year: 2023, Volume and Issue: 135, P. 133323 - 133323

Published: Feb. 23, 2023

Language: Английский

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Copper-catalyzed asymmetric C(sp2)–H arylation for the synthesis of P- and axially chiral phosphorus compounds

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: April 20, 2023

Transition metal-catalyzed C-H bond functionalization is an important method in organic synthesis, but the development of methods that are lower cost and have a less environmental impact desirable. Here, Cu-catalyzed asymmetric C(sp

Language: Английский

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Regio- and Diastereoselective Annulation of α,β-Unsaturated Aldimines with Alkenes via Allylic C(sp³)–H Activation by Rare-Earth Catalysts

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(14), P. 10187 - 10198

Published: March 28, 2024

The [3 + 2] or [4 annulation of α,β-unsaturated aldimines with alkenes via β′- γ-allylic C(sp3)–H activation is, in principle, an atom-efficient route for the synthesis five- six-membered-ring cycloalkylamines, which are important structural motifs numerous natural products, bioactive molecules, and pharmaceuticals. However, such a transformation has remained undeveloped to date probably due lack suitable catalysts. We report herein first time regio- diastereoselective annulations imines allylic by half-sandwich rare-earth catalysts having different metal ion sizes. reaction α-methyl-substituted C5Me4SiMe3-ligated scandium catalyst took place trans-diastereoselective fashion at α-methyl group (β′-position), exclusively affording alkylidene-functionalized cyclopentylamines excellent trans-diastereoselectivity. In contrast, β-methyl-substituted C5Me5-ligated cerium proceeded cis-diastereoselective activation, selectively yielding multisubstituted 2-cyclohexenylamines cis-diastereoselectivity. mechanistic details these transformations have been elucidated deuterium-labeling experiments, kinetic isotope effect studies, isolation key intermediates. This work offers efficient selective protocol new family cycloalkylamine derivatives, featuring 100% atom efficiency, high diastereoselectivity, broad substrate scope, unprecedented mechanism.

Language: Английский

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Mechanisms and Origins of Regioselectivity in Rare-Earth-Catalyzed C–H Functionalization of Anisoles and Thioanisoles

Inorganic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: March 12, 2025

The direct catalytic C–H functionalization of aromatic compounds such as anisoles and thioanisoles is great interest significance. However, achieving precise regioselectivity remains a major challenge. In this study, we conducted comprehensive density functional theory calculations to explore the mechanisms rare-earth-catalyzed regioselective alkylation, borylation, silylation anisole thioanisole. results reveal that in cationic alkylation systems, alkene insertion step follows substrate-assisted mechanism, which an additional substrate molecule acts ligand facilitate transformation. neutral borylation although mononuclear hydride species readily dimerize into binuclear due thermodynamic stability, process predominantly proceeds via pathway. Furthermore, origins were thoroughly elucidated. A detailed analysis electronic steric effects related transition states reveals that, for anisole, primarily governed by ring strain. Since α-C(sp3)–H activation involves formation highly strained three-membered ring, reaction preferentially occurs at ortho-C(sp2)–H site, forming less four-membered ring. contrast, thioanisole, play decisive role, driving more negatively charged α-C(sp3) site stronger metal–carbon interactions.

Language: Английский

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Co‐syndiospecific Alternating Copolymerization of Functionalized Propylenes and Styrene by Rare‐Earth Catalysts

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(18), P. 7173 - 7177

Published: Feb. 19, 2020

The precise control of monomer sequence and stereochemistry in copolymerization is much interest importance for the synthesis functional polymers, but studies toward this goal have met with only limited success to date. Now, co-syndiospecific alternating methoxyphenyl- N,N-dimethylaminophenyl-functionalized propylenes styrene by half-sandwich rare-earth catalysts reported. This reaction efficiently afforded corresponding functionalized propylene-alt-styrene copolymers a perfect excellent co-syndiotacticity (rrrr >99 %), thus constituting first example co-stereospecific polar non-polar olefins.

Language: Английский

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Regiodivergent C–H Alkylation of Quinolines with Alkenes by Half-Sandwich Rare-Earth Catalysts

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(42), P. 18128 - 18137

Published: Sept. 28, 2020

The regiodivergent catalysis of C–H alkylation with alkenes is great interest and importance but has remained hardly explored to date. We report herein the first quinolines by half-sandwich rare-earth catalysts. regiodivergence was achieved fine-tuning metal/ligand combination or steric electronic properties use C5Me5-ligated scandium catalyst Sc-3 for reaction styrenes that C5Me4H-ligated yttrium Y-2 aliphatic olefins exclusively afforded corresponding C8–H products, thus constituting example direct neutral quinolines. In contrast, Sc-3-catalyzed 2-arylquinolines Y-2-catalyzed selectively gave 2-aryl o-C–H products. On basis catalyst/substrate-controlled regiodivergence, sequential regiospecific dialkylation two different also been achieved. DFT studies revealed activation 2-phenylquinoline at both C8 position an ortho 2-phenyl substituent possible, these types initially formed products were interconvertible through coordination another molecule quinoline. regioselectivity reactions governed not only ease initial formation energy barriers their interconversions, as well influences in subsequent alkene insertion processes. This work constituted efficient protocol selective synthesis diversified quinoline derivatives offered unprecedented insights into transformation may help design more efficient, selective, complementary

Language: Английский

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A New Class of C₂‐Symmetric Chiral Cyclopentadienyl Ligand Derived from Ferrocene Scaffold: Design, Synthesis and Application

Chemistry - A European Journal, Journal Year: 2020, Volume and Issue: 26(64), P. 14546 - 14550

Published: May 29, 2020

Abstract A new class of C 2 ‐symmetric, chiral cyclopentadienyl ligand based on planar ferrocene backbone was developed. series its corresponding rhodium(I), iridium(I), and ruthenium(II) complexes were prepared as well. In addition, the rhodium(I) evaluated in asymmetric catalytic intramolecular amidoarylation olefin‐tethered benzamides via C−H activation.

Language: Английский

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Diastereodivergent [3 + 2] Annulation of Aromatic Aldimines with Alkenes via C–H Activation by Half-Sandwich Rare-Earth Catalysts

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(12), P. 5531 - 5537

Published: March 8, 2020

Stereodivergent catalysis is of great importance, as it can allow efficient access to all possible stereoisomers a given product with multiple stereocenters from the same set starting materials. We report herein first diastereodivergent [3 + 2] annulation aromatic aldimines alkenes via C–H activation by half-sandwich rare-earth catalysts. This protocol provides an and general route for selective synthesis both trans cis diastereoisomers multisubstituted 1-aminoindanes alkenes, featuring 100% atom efficiency, excellent diastereoselectivity, broad substrate scope, good functional group compatibility. The diastereodivergence achieved fine-tuning sterics or ligand/metal combination metal complexes.

Language: Английский

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Chiral Cyclopentadienyl Ligands: Design, Syntheses, and Applications in Asymmetric Catalysis

Angewandte Chemie, Journal Year: 2020, Volume and Issue: 133(24), P. 13306 - 13332

Published: July 16, 2020

Abstract The creation of new chiral ligands capable providing high stereocontrol in metal‐catalyzed reactions is crucial modern organic synthesis. production bioactive molecules as single enantiomers increasingly required, and asymmetric catalysis with metal complexes constitutes one the most efficient synthetic strategies to access optically active compounds. Herein we offer a historical overview on development derivatives ubiquitous cyclopentadienyl ligand (Cp X ), detail their successful application broad range transformations. Those include functionalization challenging C−H bonds beyond, giving an extensive catalogue valuable molecules. A critical comparison existing families, design, synthesis, complexation different metals also provided. In addition, future research directions are discussed further enhance performance Cp enantioselective catalysis.

Language: Английский

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