Lewis acid catalyzed asymmetric [4+2] cycloaddition of cyclobutenones to synthesize α,β-unsaturated δ-lactones

Chemical Communications, Journal Year: 2018, Volume and Issue: 54(27), P. 3375 - 3378

Published: Jan. 1, 2018

Here we report an efficient asymmetric [4+2] cycloaddition of β,γ-unsaturated α-ketoesters with cyclobutenones. The corresponding products were obtained in good yields (up to 92%) excellent enantioselectivities 98% ee) and diastereoselectivities >19/1 dr). Moreover, based on the control experiments previous reports, a possible catalytic cycle was proposed.

Language: Английский

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

Chemical Communications, Journal Year: 2021, Volume and Issue: 57(84), P. 11092 - 11095

Published: Jan. 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.

Language: Английский

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Metal-free anomalous [5+1] cycloaddition reactions of donor–acceptor aziridines for the synthesis of 2H-1,4-oxazines

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(55), P. 8572 - 8575

Published: Jan. 1, 2023

A new type of metal-free [5+1] cycloaddition reaction donor-acceptor aziridines with 2-(2-isocyanoethyl)indoles is reported herein. This method exhibits broad substrate scope and atom-economy. series 2H-1,4-oxazines containing an indole heterocycle skeleton were obtained in up to 92% yield under mild conditions. Control experiments revealed that free N-H crucial for the above transformations. The theoretical calculation studies provided guidance on in-depth insight into mechanism hydrogen-bond between carbonyl group was identified lower energy barrier transition states.

Language: Английский

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Synthesis of Diversely Substituted Imidazolidines via [3+2] Cycloaddition of 1,3,5‐Triazinanes with Donor‐Acceptor Aziridines and Their Anti‐Tumor Activity

Advanced Synthesis & Catalysis, Journal Year: 2021, Volume and Issue: 363(10), P. 2619 - 2624

Published: Feb. 26, 2021

Abstract A Y(OTf) 3 ‐catalyzed [3+2] cycloaddition of 1,3,5‐triazinanes with donor‐acceptor aziridines has been developed, accessing diversely substituted imidazolidines high efficiency. Mechanistic investigations support the formation through an S N 1‐like pathway. Furthermore, these exhibit promising anti‐tumor activity against a series human cancer cell lines. magnified image

Language: Английский

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Asymmetric Catalytic Synthesis of Hexahydropyrrolo‐isoquinolines via Three‐Component 1,3‐Dipolar‐Cycloaddition

Chemistry - A European Journal, Journal Year: 2021, Volume and Issue: 27(60), P. 14841 - 14845

Published: Aug. 16, 2021

An asymmetric three-component 1,3-dipolar cycloaddition of 3,4-dihydroisoquinolines, bromoacetates and α,β-unsaturated pyrazole amide is realized by using a chiral N,N'-dioxide-Y(OTf)3 complex as the catalyst. The process includes base-promoted formation dihydroisoquinolium ylides in situ, Lewis acid-catalyzed [3+2] with amides. A series hexahydropyrrolo-isoquinolines are obtained moderate to good yields excellent diastereo- enantioselectivities.

Language: Английский

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Cationic Divalent Metal Sites (M = Mn, Fe, Co) Operating as Both Nitrene-Transfer Agents and Lewis Acids toward Mediating the Synthesis of Three- and Five-MemberedN-Heterocycles

Inorganic Chemistry, Journal Year: 2023, Volume and Issue: 62(27), P. 10743 - 10761

Published: June 23, 2023

The tripodal compounds [(TMG

Language: Английский

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Lewis acid-catalyzed [3+3] cycloadditions of donor‒acceptor aziridines with N,N-dialkyl-3-vinylanilines via carbon-carbon bond cleavage

Tetrahedron, Journal Year: 2018, Volume and Issue: 74(27), P. 3671 - 3678

Published: May 17, 2018

Language: Английский

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Diastereoselective synthesis of functionalized tetrahydro-γ-carbolines via a [3 + 3] cycloaddition of 2,2′-diester aziridines with β-(indol-2-yl)-α,β-unsaturated ketones

Chinese Chemical Letters, Journal Year: 2019, Volume and Issue: 31(5), P. 1293 - 1296

Published: Sept. 4, 2019

Language: Английский

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Enantioselective [3+2] Cycloaddition of Donor‐Acceptor Aziridines and Imines to Construct 2,5‐trans‐Imidazolidines

Chemistry - A European Journal, Journal Year: 2023, Volume and Issue: 29(18)

Published: Jan. 5, 2023

An enantioselective [3+2] cycloaddition of donor-acceptor aziridines with N-aryl protected imines was developed a Ni(ClO4 )2 ⋅ 6H2 O/N,N'-dioxide catalyst system, providing broad range chiral trans-substituted imidazolidine compounds good yields and excellent enantioselectivities (up to 99 % yield, up 98 ee). Control experiments indicated that the products could offer diastereoselectivities control Ni(II)-N,N'-dioxide complex interaction substrates. The possible catalytic process proposed rationalize stereocontrol.

Language: Английский

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Recent Advances in Cycloaddition Reactions of Donor-Acceptor Aziridines via Carbon-Carbon Bond Cleavage

Chinese Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 43(9), P. 3078 - 3078

Published: Jan. 1, 2023

There are two different ring-opening modes of aziridines: aziridines via carbon-nitrogen bond cleavage, and carbon-carbon cleavage.Among them, the reaction cleavage has been reported in many reviews.The cycloaddition reactions donor-acceptor (D-A) recent 20 years mainly summarized.Under some proper catalysts, D-A yield azomethine ylides, which can undergo [3＋n] with aldehydes, imines, alkenes, alkynes, indoles etc.

Language: Английский

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