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

Organic Letters, Год журнала: 2024, Номер 26(17), С. 3487 - 3492

Опубликована: Апрель 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.

Язык: Английский

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Asymmetric synthesis of 1H-pyrazolo[3,4-b]pyridine analogues catalyzed by chiral-at-metal Rh(iii) complexes

Organic Chemistry Frontiers, Год журнала: 2024, Номер 11(19), С. 5385 - 5389

Опубликована: Янв. 1, 2024

An efficient asymmetric Friedel–Crafts-type alkylation/cyclization of 5-aminopyrazoles has been developed, affording corresponding pyrazolo[3,4- b ]pyridine analogues.

Язык: Английский

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Regio- and Enantioselective N-Heterocyclic Carbene-Catalyzed Annulation of Aminoindoles Initiated by Friedel–Crafts Alkylation

Organic Letters, Год журнала: 2024, Номер 26(33), С. 6993 - 6998

Опубликована: Авг. 8, 2024

Chiral indoles annulated on the benzene ring are unique and significant in natural medicinal compounds. However, accessing these enantioenriched molecules has often been overlooked. The present study introduces an organocatalytic protocol to access compounds efficiently, demonstrated by substrate scope, functional group tolerance, using only 1 mol % of a chiral conjugated acid catalyst. Additionally, explores regioselectivity, gram-scale reactions, follow-up transformations, underscoring method's potential.

Язык: Английский

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Chiral Phosphoric Acid-Catalyzed Asymmetric Synthesis of Axially Chiral Arylpyrazole

Organic Letters, Год журнала: 2025, Номер 27(4), С. 932 - 936

Опубликована: Янв. 23, 2025

A chiral phosphoric acid-catalyzed efficient, operationally simple, general method for straightforward syntheses of axially arylpyrazole employing N-alkyl 3-aryl-5-aminopyrazoles reacting with azonaphthalenes was achieved. wide variety heterobiaryl diamines in generally good yields excellent enantioselectivities were obtained under mild conditions. In addition, a scaled-up experiment and postmodification the product further highlighted synthetic utility.

Язык: Английский

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NHC‐Catalyzed Remote γ,δ–Protonation and Formal [3+3] Annulation to Access Functionalized Dihydropyridinones

Asian Journal of Organic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Апрель 8, 2025

Abstract We have developed an N ‐heterocyclic carbene (NHC)‐catalyzed [3+3] annulation of α,β−γ,δ‐unsaturated aldehydes with enamines for the asymmetric synthesis dihydropyridinone that bearing all‐carbon quaternary center. This strategy proceeding via NHC‐mediated γ,δ–protonation α,β−γ,δ−unsaturated aldehydes, followed by cycloadditions. protocol delivers a wide range substituited dihydropyridinones in good yields excellent enantioselectivities.

Язык: Английский

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Asymmetric electrophilic functionalization of amino-substituted heteroaromatic compounds: a convenient tool for the enantioselective synthesis of nitrogen heterocycles.

Chemical Communications, Год журнала: 2024, Номер unknown

Опубликована: Янв. 1, 2024

The catalytic asymmetric electrophilic functionalization of the less reactive N-heteroaromatic compounds has been reported using approach introduction an exocyclic amino substituent.

Язык: Английский

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PIFA-Mediated Intramolecular Dearomatization of Phenol-Tethered 1,2-Diazoles: Synthesis of Spirocyclohexadienone Pyrazolo[3,4-b]piperidinones

Synthesis, Год журнала: 2024, Номер unknown

Опубликована: Авг. 8, 2024

Abstract In recent years, the significance of spirocyclic motifs in drug discovery has increased, owing to their unique ability engage biological targets. We present first example PIFA-mediated dearomative spirocyclization phenol-tethered pyrazoles, highlighting intramolecular trapping by pyrazole moiety. This method efficiently affords a variety spirocyclohexadienone-pyrazolo[3,4-b]piperidinones with yields up 82%. Mechanistic studies reveal that dearomatization process involves cationic intermediate.

Язык: Английский

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Mechanisms and Origins of Regio- and Stereoselectivities in NHC-Catalyzed [3 + 3] Annulation of α-Bromoenals and 5-Aminoisoxazoles: A DFT Study

The Journal of Organic Chemistry, Год журнала: 2024, Номер 89(15), С. 10748 - 10759

Опубликована: Июль 12, 2024

Density functional theory (DFT) calculations were conducted to explore the mechanisms and origins of regio- stereoselectivities underlying [3 + 3] annulation reaction between α-bromoenals 5-aminoisoxazoles with

Язык: Английский

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Asymmetric Synthesis of Polycyclic Heterocyclic Compounds via Friedel–Crafts Reaction/Cyclization Reaction Catalyzed by Nickel Catalyst

Organic Letters, Год журнала: 2024, Номер 26(46), С. 9877 - 9884

Опубликована: Ноя. 11, 2024

The first highly enantioselective asymmetric Friedel-Crafts reaction/cyclization reaction of 5-aminopyrazoles with 3-alkenyloxindoles to afford polycyclic heterocyclic compounds bearing an all-carbon quaternary stereocenter catalyzed by a complex Ni

Язык: Английский

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