Bipyridine-N,N′-dioxides Catalysts: Design, Synthesis, and Application in Asymmetric Synthesis of 1H-Pyrazolo[3,4-b]pyridine Analogues

Organic Letters, Journal Year: 2024, Volume and Issue: 26(17), P. 3487 - 3492

Published: April 18, 2024

A novel type of highly efficient chiral C2-symmetric bipyridine-N,N′-dioxides ligand application in catalyzing Michael addition/Cyclization 5-aminopyrazoles with α,β-unsaturated 2-acyl imidazoles has been developed, affording the corresponding adducts 85–97% yield up to 99% enantioselectivity under mild conditions a lower catalyst loading and broad scope. Remarkably, this protocol exhibits advantages terms reactivity enantioselectivity, giving fact that as low 2.2 mol % L1 2.0 Ni(OTf)2 can promote title reaction on gram scale afford desired product excellent enantioselectivity.

Language: Английский

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Oxalyl Monoamide Ligand-Promoted Palladium-Catalyzed Suzuki Coupling Reactions in Aqueous Media at Low Doses

Acta Chimica Sinica, Journal Year: 2025, Volume and Issue: 83(4), P. 354 - 354

Published: Jan. 1, 2025

Language: Английский

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Development of Eagle‐Shaped BPE/Phe‐2NO Ligands: Switch of Enantioselectivity in Friedel–Crafts Alkylation

Chemistry - An Asian Journal, Journal Year: 2025, Volume and Issue: unknown

Published: April 25, 2025

Abstract The development of single chiral source‐derived ligands to fine‐switch enantioselectivity has been a key aspect in asymmetric catalysis. Herein, this study, using the same source l ‐prolinamide as starting material, we synthesize 14 new diphenyl ether bridged C 2 ‐symmetric rigid tertiary amine‐derived dioxide (abberviated BPE‐2NO) and 9 m ‐phenylene Phe‐2NO); their effectiveness was demonstrated first switch palladium(II)‐catalyzed Friedel–Crafts alkylation. In presence palladium acetate Lewis acid, both enantiomers indole derivatives can be prepared good‐to‐excellent yields enantioselectivities by Eagle‐shaped BPE/Phe‐2NO ligands. Control experiments density functional theory calculations provide rational explanation for above observations. This study alkylation

Language: Английский

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Green solvent-controlled switchable synthesis of six-membered N-heterocycles and seven-membered O-heterocycles

Green Synthesis and Catalysis, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 1, 2024

Language: Английский

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Modular Synthesis of C₂‐Symmetric Chiral TPy‐BPI Pincer Ligands and Application in Asymmetric Ni(II)‐Catalysed Friedel‐Crafts Alkylation

Chinese Journal of Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 17, 2024

Comprehensive Summary Terpyridine ligands have been applied as a class of unique due to their rich coordination chemistry in the catalysis. Herein, we developed new C 2 ‐symmetric chiral terpyridine‐pyrroloimidazolone (TPy‐BPI). Their catalytic activity was evaluated asymmetric Friedel‐Crafts alkylation indoles with 2,3‐dioxopyrrolidines. Excellent yields (up 92%) and high enantioselectivities 97% ee) are obtained for wide range substrates under mild conditions. In addition 2,3‐dioxopyrrolidines, β , γ ‐unsaturated α ‐ketoesters were also compatible Ni(OTf) ‐TPy‐BPI ligand L1 ‐catalyzed reaction. Control experiments, single crystal structure two TPy‐BPI ‐Ni(OTf) complexes, DFT calculations revealed origins enantioselectivity. To best our knowledge, work is first report showing that terpyridine framework contained only nitrogen atoms coordinating metal, additional pyridine unit acted stereodirecting element, which different from previously reported containing all three metal.

Language: Английский

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Asymmetric Synthesis of Optically Active Pyrazolidines or Pyrazoline Derivatives via Ni(II)-Bipyridine-N,N′-dioxide Complexes

Organic Letters, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 25, 2024

Easily obtainable and efficient chiral

Language: Английский

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