Catalytic Asymmetric Chemodivergent C2 Alkylation and [3 + 2]-Cycloaddition of 3-Methylindoles with Aziridines

ACS Catalysis, Год журнала: 2018, Номер 8(11), С. 10261 - 10266

Опубликована: Окт. 3, 2018

Highly enantioselective C2 alkylation and inverse-electron-demand [3 + 2]-cycloaddition of 3-methylindoles with 2,2′-diester aziridine were accomplished. The chemodivergent synthesis provided an access to two kinds chiral indole derivatives in good yields stereoselectivities the presence N,N′-dioxide/Tm(OTf)3 or N,N′-dioxide/Ho(OTf)3 complexes. An eight-coordinated mode complex was confirmed by X-ray crystal diffraction interpret roles additives H2O 1,4-dioxane. In addition, control experiments indicated that substituent nitrogen atom determined conversion patterns divergent reactions.

Язык: Английский

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Enantioselective [3+2] cycloaddition of azomethine ylides and aldehydes via Ni/bis(oxazoline)-catalyzed ring opening of N-tosylaziridines through a chirality transfer approach

Chemical Communications, Год журнала: 2017, Номер 53(41), С. 5661 - 5664

Опубликована: Янв. 1, 2017

An enantioselective [3+2] cycloaddition of N-tosylaziridines and aldehydes catalyzed by a Ni(ii)-bisoxazoline complex has been accomplished through chirality transfer approach.

Язык: Английский

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Enantioselective Synthesis of Azetidines through [3 + 1]-Cycloaddition of Donor–Acceptor Aziridines with Isocyanides

Organic Letters, Год журнала: 2022, Номер 24(7), С. 1513 - 1517

Опубликована: Фев. 11, 2022

The enantioselective [3 + 1]-cycloaddition of racemic donor-acceptor (D-A) aziridines with isocyanides was first realized under mild reaction conditions using a chiral N,N'-dioxide/MgII complex as catalyst, providing facile route to enantioenriched exo-imido azetidines good excellent yield (up 99%) and enantioselectivity 94% ee). An obvious amplification effect observed in this system, an explanation elucidated based on the experimental investigation X-ray crystal structure enantiomerically pure catalyst.

Язык: Английский

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Accessing polysubstituted oxazolidines, pyrrolidines and imidazolidines by regioselective [3 + 2] annulations of ketenimines with donor–acceptor oxiranes and aziridines

Organic Chemistry Frontiers, Год журнала: 2018, Номер 5(13), С. 2020 - 2029

Опубликована: Янв. 1, 2018

Diverse five-membered rings result from formal [3 + 2] cycloadditions of ketenimines with carbonyl and azomethine ylides.

Язык: Английский

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Palladium-Catalyzed Annulative Coupling of Spirovinylcyclopropyl Oxindoles with p-Quinone Methides

The Journal of Organic Chemistry, Год журнала: 2023, Номер 88(14), С. 9704 - 9719

Опубликована: Июль 12, 2023

Pd-catalyzed annulative coupling of spirovinylcyclopropyl oxindoles with p-quinone methides has been accomplished via cascade carbon–carbon bond formation to afford bis-spirooxindole scaffolds. The mild reaction conditions, diastereoselectivity, functional group diversity, post-synthetic transformations, and mechanistic studies using DFT calculations are the important practical features.

Язык: Английский

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Catalytic Asymmetric Epoxidation of Electron‐Deficient Enynes Promoted by Chiral N,N′‐Dioxide‐Scandium(III) Complex

Advanced Synthesis & Catalysis, Год журнала: 2017, Номер 359(19), С. 3454 - 3459

Опубликована: Июль 27, 2017

Abstract An asymmetric epoxidation of electron‐deficient enynes with environmentally benign aqueous hydrogen peroxide as oxidant has been accomplished by developing a chiral N,N′ ‐dioxide‐Scandium(III) complex catalytic system. In the presence 0.5–2 mol% catalyst, variety trisubstituted alkynyl oxiranes were obtained in high yields (up to 97%) excellent ee values 99%). Furthermore, control experiments provide fundamental insight into reaction mechanism. magnified image

Язык: Английский

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N,N′‐Dioxide–Lanthanum(III)‐Catalyzed Asymmetric Cyclopropanation of 2‐Cyano‐3‐arylacrylates with 2‐Bromomalonates

Advanced Synthesis & Catalysis, Год журнала: 2017, Номер 359(11), С. 1831 - 1836

Опубликована: Март 20, 2017

Abstract An efficient N , N′ ‐dioxide–lanthanum(III) complex catalytic system has been developed for the diastereo‐ and enantioselective Michael‐initiated ring‐closure (MIRC) reaction of 2‐cyano‐3‐arylacrylates with 2‐bromomalonates. Various chiral cyclopropanes multiple substitutions were obtained in high yields (up to 93%) excellent dr (>95:5 ) good ee values 91% ). The also worked tandem halogenation/asymmetric MIRC α,β‐unsaturated nitriles, malonates NBS. Besides, a possible model proposed explain origin stereoselectivity. magnified image

Язык: Английский

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Lewis Acid‐Catalyzed Intramolecular [3+2] Cross‐Cycloaddition of Aziridine 2,2‐Diesters with Conjugated Dienes for Construction of Aza‐[n.2.1] Skeletons

Chemistry - A European Journal, Год журнала: 2017, Номер 23(71), С. 17862 - 17866

Опубликована: Окт. 25, 2017

A novel Lewis acid-catalyzed [3+2] intramolecular cross-cycloaddition (IMCC) between aziridine 2,2-diesters and conjugated dienes has been developed. This is the first regiospecific IMCC of 1,3-dipolar cycloadditions azomethine ylides with carbon=carbon double bonds, supplies a general efficient strategy for construction structurally complex diverse aza-[n.2.1] skeletons. The [3+2]IMCC could be carried out under mild conditions in gram scale. More importantly, 3-alkyl-substituted aziridines were also successful. excellent structural diversity, facile operation versatile post-modifications will support applications natural products synthesis drugs discovery.

Язык: Английский

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Construction of 1,3-Oxazolidines through a Three-Component [3+2] Cycloaddition of Tetrahydroisoquinolines, Aldehydes, and Ethyl Ketomalonate

The Journal of Organic Chemistry, Год журнала: 2020, Номер 85(9), С. 6216 - 6224

Опубликована: Апрель 9, 2020

A chemoselective and diastereoselective synthesis of fused oxazolidines was achieved by a three-component cascade reaction tetrahydroisoquinolines (THIQs), α,β-unsaturated aldehydes, diethyl 2-oxomalonate. Probably due to the reactivity difference between aldehyde ketone, proceeded through condensation THIQs with aldehydes 1,3-dipolar cycloaddition generated azomethine ylide intermediate The key features are easily available starting materials, mild conditions, broad substrate scope, high chemo- diastereoselectivity.

Язык: Английский

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Synthesis of polycyclic spiroindolines via the cascade reaction of 3-(2-isocyanoethyl)indoles

Chemical Communications, Год журнала: 2021, Номер 57(84), С. 11092 - 11095

Опубликована: Янв. 1, 2021

Tandem reactions of the yttrium(iii) catalyzed ring-opening reaction 2,2'-diester aziridines with 3-(2-isocyanoethyl)indoles and subsequent Friedel-Crafts/Mannich/desulfonylation were reported. A series polycyclic spiroindolines containing tetrahydro-β-carbolines obtained in moderate to excellent yields (56-92%) one step under mild conditions. possible catalytic mechanism was also proposed.

Язык: Английский

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