Sc-Catalyzed Asymmetric [2 + 2] Annulation of 2-Alkynylnaphthols with Dienes to Access Cyclobutene Frameworks DOI
Ke Xu, Heping Li,

Yan‐Ling Ji

и другие.

Organic Letters, Год журнала: 2025, Номер 27(4), С. 1006 - 1011

Опубликована: Янв. 16, 2025

Herein, we introduce a scandium-catalyzed synthetic strategy that provides access to diverse and functionalized array of cyclobutene frameworks adorned with quaternary carbon center. This approach broadens the repertoire 2-alkynylnaphthols alkenes, offering versatile platform for construction complex molecular architectures. The asymmetric catalytic [2 + 2] cycloaddition reaction demonstrates wide substrate scope an impressive functional group tolerance, yielding products high efficiency, up 97% yield, excellent enantiomeric excess 97%. simplicity scaling this process, coupled ease converting these into variety substituted products, significantly enhances utility method.

Язык: Английский

Enantioselective Synthesis of 3‐Substituted Cyclobutenes by Catalytic Conjugate Addition/Trapping Strategies DOI

Changxu Zhong,

Yingchao Huang,

Haocheng Zhang

и другие.

Angewandte Chemie International Edition, Год журнала: 2019, Номер 59(7), С. 2750 - 2754

Опубликована: Дек. 12, 2019

A copper-catalyzed tandem process to generate chiral cyclobutene derivatives has been developed. It is based on an enantioselective conjugate addition or reduction of a cyclobutenone and sequential trapping with chlorophosphate in one-pot process. These phosphates are stable under mildly acidic conditions serve as good electrophiles Negishi coupling reactions.

Язык: Английский

Процитировано

45
Acetylene as a Dicarbene Equivalent for Gold(I) Catalysis: Total Synthesis of Waitziacuminone in One Step DOI Creative Commons
Dagmar Scharnagel, Imma Escofet, Helena Armengol‐Relats

и другие.

Angewandte Chemie International Edition, Год журнала: 2020, Номер 59(12), С. 4888 - 4891

Опубликована: Янв. 8, 2020

Abstract The gold(I)‐catalyzed reaction of acetylene gas with alkenes leads to (Z,Z)‐1,4‐disubstituted 1,3‐butadienes and biscyclopropanes depending on the donor ligand gold(I). Acetylene was generated in situ from calcium carbide water a user‐friendly procedure. Reaction 1,5‐dienes gives rise stereoselectively tricyclo[5.1.0.0 2,4 ]octanes. This novel double cyclopropanation has been applied one step total synthesis natural product waitziacuminone geranyl acetone.

Язык: Английский

Процитировано

42
Bifunctional Borane Catalysis of a Hydride Transfer/Enantioselective [2+2] Cycloaddition Cascade DOI
Ming Zhang, Xiaochen Wang

Angewandte Chemie International Edition, Год журнала: 2021, Номер 60(31), С. 17185 - 17190

Опубликована: Май 26, 2021

Abstract Herein, we present a mild and efficient method for synthesizing enantioenriched tetrahydroquinoline‐fused cyclobutenes through cascade reaction between 1,2‐dihydroquinolines alkynones with catalysis by chiral spiro‐bicyclic bisboranes. The bisboranes served two functions: first they catalyzed hydride transfer to convert the 1,2‐dihydroquinoline substrate 1,4‐dihydroquinoline, then activated alkynone an enantioselective [2+2] cycloaddition 1,4‐dihydroquinoline generated in situ.

Язык: Английский

Процитировано

38
Enantioselective [2+2] Cycloaddition of Allenyl Imide with Mono‐ or Disubstituted Alkenes DOI
Wanlong Xiao, Lichao Ning, Shuang Xin

и другие.

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(44)

Опубликована: Сен. 14, 2022

Abstract An efficient catalytic asymmetric [2+2] cycloaddition of allenyl imide and mono‐ or disubstituted alkenes is disclosed. The key feature this method the use bidentate weakly activated less steric hindered alkene pair by utilizing chiral magnesium(II) complex N , N′ ‐dioxide, which could provide through‐space dispersion interactions to orientate arrangement alkene. This protocol allows generation a series axially cyclobutenes four‐membered ring‐containing spirocycles (80 examples) in high yield (up 99 %) with excellent enantioselectivity >99 % ee ), late‐stage modification biologically active molecules as well. Experimental studies DFT calculations revealed that proceeded via stepwise mechanism involving short‐lived zwitterionic intermediate. π‐π interaction between amide moiety ligand was crucial for enantiocontrol.

Язык: Английский

Процитировано

23
Sc-Catalyzed Asymmetric [2 + 2] Annulation of 2-Alkynylnaphthols with Dienes to Access Cyclobutene Frameworks DOI
Ke Xu, Heping Li,

Yan‐Ling Ji

и другие.

Organic Letters, Год журнала: 2025, Номер 27(4), С. 1006 - 1011

Опубликована: Янв. 16, 2025

Herein, we introduce a scandium-catalyzed synthetic strategy that provides access to diverse and functionalized array of cyclobutene frameworks adorned with quaternary carbon center. This approach broadens the repertoire 2-alkynylnaphthols alkenes, offering versatile platform for construction complex molecular architectures. The asymmetric catalytic [2 + 2] cycloaddition reaction demonstrates wide substrate scope an impressive functional group tolerance, yielding products high efficiency, up 97% yield, excellent enantiomeric excess 97%. simplicity scaling this process, coupled ease converting these into variety substituted products, significantly enhances utility method.

Язык: Английский

Процитировано

0