Modular Synthesis of C2‐Symmetric Chiral TPy‐BPI Pincer Ligands and Application in Asymmetric Ni(II)‐Catalysed Friedel‐Crafts Alkylation DOI Open Access
Hong Cen, Liping Ding,

L.L. Liu

et al.

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

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

Shijie Zhu,

Xue Tian, Jichang Liu

et al.

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

Citations

7
Chiral Phenol‐2NO Ligand Cooperation with Achiral Organic Base in the Zn(II)‐Catalyzed Asymmetric Alkylation Reaction of Indoles DOI

Ke‐Lan Xu,

Yuheng Wang, Xirui Wang

et al.

Chinese Journal of Chemistry, Journal Year: 2024, Volume and Issue: 42(13), P. 1474 - 1480

Published: March 1, 2024

Comprehensive Summary The privileged C 2 ‐symmetric rigid phenol‐type ligand is more attractive but challenging in asymmetric catalysis. Herein, we designed and synthesized a class of rigid‐featured chiral tridentate Phenol‐2NO ligands, that incorporate the advantages both phenol skeleton pyrroloimidazolone‐based N ‐oxide moiety, from readily available L ‐prolinamides operationally simple two steps up to 44% overall yield. More importantly, using an achiral quinoline derivative as additive, newly developed could serve anioic upon deprotonative activation coordinate Zn(II) form highly enantioselective catalyst for Michael‐type Friedel‐Crafts alkylation reaction indoles with 2,3‐dioxopyrrolidines. Excellent yields (up 90%) high enantioselectivities 99% ee) are obtained wide range substrates under mild conditions. Experiments DFT calculations revealed mechanism origins enantioselectivity. This also represented first ligand/metal complex by organic base additive

Language: Английский

Citations

5
Development of Eagle‐Shaped BPE/Phe‐2NO Ligands: Switch of Enantioselectivity in Friedel–Crafts Alkylation DOI
Jun Young Yang,

Jing Lou,

Wei Li

et al.

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

Citations

0
Phen-2NO, a new C2-symmetric rigid-featured tetradentate ligand, and its application in the asymmetric alkylation reaction of indoles DOI

Zi‐Yue Chen,

Ke‐Lan Xu,

Xirui Wang

et al.

New Journal of Chemistry, Journal Year: 2024, Volume and Issue: 48(15), P. 6670 - 6675

Published: Jan. 1, 2024

A new class of C 2 -symmetric rigid-featured chiral phen ligands that provide the N , O -tetradentate coordination moiety and two additional -dioxides were rationally designed developed.

Language: Английский

Citations

3
Naphthyridine–2NO, a new C2-symmetric rigid tetradentate bimetallic ligand and its application in asymmetric Friedel–Crafts alkylation DOI
Pan Hu,

Ke‐Lan Xu,

Xirui Wang

et al.

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(9), P. 2600 - 2606

Published: Jan. 1, 2024

The development of a series novel and easily accessed chiral naphthyridine-type binucleating ligands for asymmetric catalysis.

Language: Английский

Citations

3
Modular Synthesis of C2‐Symmetric Chiral TPy‐BPI Pincer Ligands and Application in Asymmetric Ni(II)‐Catalysed Friedel‐Crafts Alkylation DOI Open Access
Hong Cen, Liping Ding,

L.L. Liu

et al.

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

Citations

0