Enantioselective Friedel–Crafts alkylation of indoles with β,γ-unsaturated α-ketoesters catalyzed by new squaramide-linked bisoxazoline–Zn(OTf)2 complexes

Jia, Sheng‐Jian; Du, Da‐Ming

doi:10.1016/j.tetasy.2014.05.011

Cited by 15 publications

(4 citation statements)

References 66 publications

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“…8 Using chiral C 2 -symmetric squaramide-linked bisoxazoline-Zn(OTf) 2 as the catalyst, reactions of indoles with β,γ-unsaturated α-ketoesters at 0 °C provided the desired products in good to excellent yields and up to 94% enantiomeric excess (Scheme 1). 9 Low reaction temperatures were generally applied to ensure high stereoselectivity of the reactions due to the high reactivity of indoles and β,γunsaturated α-ketoesters. It is highly desirable to develop reaction systems, which can be easily handled and operated under mild conditions.…”

Section: ■ Introductionmentioning

confidence: 99%

Enantioselective Friedel–Crafts Alkylation of Indoles with β,γ-Unsaturated α-Ketoesters Catalyzed by New Copper(I) Catalysts

Cai

Wang

et al. 2023

J. Org. Chem.

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New Cu(I) catalysts are effective in enantioselective Friedel–Crafts alkylation of a variety of indoles with different β,γ-unsaturated α-ketoesters. A control study shows that such a catalyst system is less sensitive to air, and the reactions can be carried out without special cares such as glovebox operation or moisture/oxygen-free conditions. Preliminary computation results suggest that there exists π–π stacking between the substrate and the catalyst, and such an interaction seems to play a role in stabilizing the reaction intermediate and enhancing the stereoselectivity of the reactions. The desired products can be obtained in up to 98% yield at 99% enantiomeric excess. The same high enantioselectivity can be observed when the reaction is carried in a gram scale, indicating a good scalability of the catalyst system in enantioselective Friedel–Crafts alkylation of different indoles with β,γ-unsaturated α-ketoesters.

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Section: ■ Introductionmentioning

confidence: 99%

Enantioselective Friedel–Crafts Alkylation of Indoles with β,γ-Unsaturated α-Ketoesters Catalyzed by New Copper(I) Catalysts

Cai

Wang

et al. 2023

J. Org. Chem.

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“…1) [46]. Thus, it occurred to us to evaluate these types of ligands for Lewis acid catalyzed enantioselective chlorination of keto esters with NCS.…”

Section: Resultsmentioning

confidence: 99%

Enantioselective chlorination of β-keto esters and amides catalyzed by chiral copper(II) complexes of squaramide-linked bisoxazoline ligand

Jia

2014

Chinese Chemical Letters

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“…Catalysis by chiral magnesium complexes is preliminary associated with aldol condensation reaction, Diels‐Alder reaction, dipolar cycloaddition, and for the Friedel‐Crafts reaction there are only scarce examples of employing magnesium salts as catalysts ,. In contrast, there is a large number of asymmetric Friedel‐Crafts reactions catalyzed with the chiral complexes of copper, scandium, lanthanides, palladium, zinc, and indium …”

Section: Introductionmentioning

confidence: 99%

The Asymmetric Friedel‐Crafts Reaction of Indoles with Arylidenemalonates Catalyzed by MgI₂/PyBox Complexes

et al. 2018

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A mild and efficient catalytic enantioselective addition of indoles to dimethyl arylidenemalonates using MgI2 and PyBOX ligands bearing halogen substituents has been elaborated. The reactions were conducted in DCM at low temperature generally providing high yields (up to 99%), while enantioselectivity was shown to be strongly dependent on the nature of substituents in arylidenemalonate and indole reaching 83% ee. The reactivity of arylidenemalonates under described conditions was found to be enough different from that in copper‐catalyzed Friedel‐Crafts alkylation.

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Enantioselective Friedel–Crafts alkylation of indoles with β,γ-unsaturated α-ketoesters catalyzed by new squaramide-linked bisoxazoline–Zn(OTf)2 complexes

Cited by 15 publications

References 66 publications

Enantioselective Friedel–Crafts Alkylation of Indoles with β,γ-Unsaturated α-Ketoesters Catalyzed by New Copper(I) Catalysts

Enantioselective Friedel–Crafts Alkylation of Indoles with β,γ-Unsaturated α-Ketoesters Catalyzed by New Copper(I) Catalysts

Enantioselective chlorination of β-keto esters and amides catalyzed by chiral copper(II) complexes of squaramide-linked bisoxazoline ligand

The Asymmetric Friedel‐Crafts Reaction of Indoles with Arylidenemalonates Catalyzed by MgI₂/PyBox Complexes

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Enantioselective Friedel–Crafts alkylation of indoles with β,γ-unsaturated α-ketoesters catalyzed by new squaramide-linked bisoxazoline–Zn(OTf)2 complexes

Cited by 15 publications

References 66 publications

Enantioselective Friedel–Crafts Alkylation of Indoles with β,γ-Unsaturated α-Ketoesters Catalyzed by New Copper(I) Catalysts

Enantioselective Friedel–Crafts Alkylation of Indoles with β,γ-Unsaturated α-Ketoesters Catalyzed by New Copper(I) Catalysts

Enantioselective chlorination of β-keto esters and amides catalyzed by chiral copper(II) complexes of squaramide-linked bisoxazoline ligand

The Asymmetric Friedel‐Crafts Reaction of Indoles with Arylidenemalonates Catalyzed by MgI2/PyBox Complexes

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The Asymmetric Friedel‐Crafts Reaction of Indoles with Arylidenemalonates Catalyzed by MgI₂/PyBox Complexes