Asymmetric Catalytic Reactions of Donor–Acceptor Cyclopropanes DOI
Yong Xia, Xiaohua Liu, Xiaoming Feng

et al.

Angewandte Chemie, Journal Year: 2020, Volume and Issue: 133(17), P. 9276 - 9288

Published: July 28, 2020

Abstract Due to the synergistic “push–pull” effect of vicinal electron‐donating and electron‐withdrawing groups, donor–acceptor (D‐A) cyclopropanes have been recognized as one most powerful building blocks generate polyfunctional reactive intermediates after a strain‐driven ring cleavage. Enantioselective reactions D‐A provide an efficient approach enantioenriched acyclic cyclic compounds. A number chiral Lewis/Brønsted acids, transition metals, organocatalysts designed for such transformations, including ring‐openings, annulations, rearrangements. This minireview highlights developments new advances in this field describes synthetic opportunities offered by these interesting methodologies.

Language: Английский

Anthranils: versatile building blocks in the construction of C–N bonds and N-heterocycles DOI Open Access
Yang Gao,

Jianhong Nie,

Yanping Huo

et al.

Organic Chemistry Frontiers, Journal Year: 2020, Volume and Issue: 7(9), P. 1177 - 1196

Published: Jan. 1, 2020

This review article provides an overview of the recent progress in transformations anthranils, which have emerged as versatile building blocks assembly various C–N bonds and medicinally active heterocyclic systems.

Language: Английский

Citations

54
Recent Advancement in Palladium-Catalyzed C–C Bond Activation of Strained Ring Systems: Three- and Four-Membered Carbocycles as Prominent C3/C4 Building Blocks DOI
Tanmayee Nanda,

Muhammed Fastheem,

Astha Linda

et al.

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(21), P. 13247 - 13281

Published: Oct. 17, 2022

In recent years, transition metal-catalyzed strong C–C bond activation has significantly attracted the attention of synthetic chemists. This protocol enables simultaneous and direct functionalization two different M–C bonds. Among types strategies, strain-driven resulted in various otherwise difficult transformations. this context, palladium catalyst been extensively used studied due to its robust reactivity selectivity. Herein we have briefly discussed palladium-catalyzed three- four-membered cycloalkane derivatives.

Language: Английский

Citations

34
A novel type of donor–acceptor cyclopropane with fluorine as the donor: (3 + 2)-cycloadditions with carbonyls DOI Creative Commons
Haidong Liu, Lifang Tian, Hui Wang

et al.

Chemical Science, Journal Year: 2022, Volume and Issue: 13(9), P. 2686 - 2691

Published: Jan. 1, 2022

A new type of donor–acceptor cyclopropane with gem -difluorine as an unconventional donor group undergoes (3 + 2)-cycloadditions various aldehydes/ketones, affording densely functionalized -difluorotetrahydrofurans.

Language: Английский

Citations

33
(4+3) Annulation of Donor‐Acceptor Cyclopropanes and Azadienes: Highly Stereoselective Synthesis of Azepanones DOI Creative Commons
Stefano Nicolai, Jérôme Waser

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(36)

Published: July 14, 2022

Azepanes are important seven-membered heterocycles, which present in numerous natural and synthetic compounds. However, the development of convergent methods to access them remains challenging. Herein, we report Lewis acid catalyzed (4+3) annulative addition aryl amino donor-acceptor cyclopropanes with 2-aza-1,3-dienes. Densely substituted azepane derivatives were obtained good excellent yields high diastereoselectivity. The reaction occurred under mild conditions ytterbium triflate as catalyst. use copper a trisoxazoline (Tox) ligand led an enantioselective transformation. cycloadducts convenient substrates for series further modifications, showing utility these

Language: Английский

Citations

29
Synthesis of Chiral Endocyclic Allenes and Alkynes via Pd-Catalyzed Asymmetric Higher-Order Dipolar Cycloaddition DOI

Bin Shi,

Meng Xiao,

Jin-Pu Zhao

et al.

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 18, 2024

A Pd-catalyzed asymmetric higher-order dipolar cycloaddition between allenyl carbonates and azadienes is achieved by exploiting novel alkylidene-π-allyl-Pd dipoles. This research provides a modular platform for the synthesis of challenging chiral endocyclic allenes bearing medium-sized heterocyclic motif centrally stereocenter in good yields with high enantio- diastereoselectivities (29 examples, up to 97% yield, 97:3 er >19:1 dr). Experimental computational studies elucidate possible reaction mechanism observed stereochemical results. Based on mechanistic understanding, new π-propargyl-Pd dipole was designed further extend success higher order strategy 10-membered alkynes from propargyl (13 98% yield 94.5:5.5 er).

Language: Английский

Citations

8
Enantioselective dearomative [3+2] cycloaddition of 2-nitrobenzofurans with aldehyde-derived Morita–Baylis–Hillman carbonates DOI

Xin-He Yang,

Jianping Li, Dong‐Chao Wang

et al.

Chemical Communications, Journal Year: 2019, Volume and Issue: 55(62), P. 9144 - 9147

Published: Jan. 1, 2019

The phosphine-catalyzed asymmetric dearomative [3+2] cycloaddition of 2-nitrobenzofurans with aldehyde-derived Morita-Baylis-Hillman (MBH) carbonates or allenoate was developed. reaction MBH resulted in a series cyclopentabenzofurans containing three contiguous stereocenters good to high yields, diastereoselectivities and enantioselectivities. use also gave the target product moderate enantioselectivity.

Language: Английский

Citations

52
Base-Mediated [3 + 4]-Cycloaddition of Anthranils with Azaoxyallyl Cations: A New Approach to Multisubstituted Benzodiazepines DOI
Juan Feng,

Meng Zhou,

Xuanzi Lin

et al.

Organic Letters, Journal Year: 2019, Volume and Issue: 21(16), P. 6245 - 6248

Published: Aug. 1, 2019

A new [3 + 4] cycloaddition of azaoxyallyl cations and anthranils has been achieved for rapid access to multisubstituted benzodiazepine derivatives. variety α-halo hydroxamates were both effective substrates with simple operations under transition-metal-free conditions. The intriguing features this method include its mild nature the reaction conditions, high efficiency, broad substrate scope, wide functional group compatibility.

Language: Английский

Citations

52
Zinc‐Catalyzed Asymmetric Formal [4+3] Annulation of Isoxazoles with Enynol Ethers by 6π Electrocyclization: Stereoselective Access to 2H‐Azepines DOI
Xin‐Qi Zhu, Ze‐Shu Wang,

Bo‐Shang Hou

et al.

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 59(4), P. 1666 - 1673

Published: Nov. 14, 2019

6π electrocyclization has attracted interest in organic synthesis because of its high stereospecificity and atom economy the construction versatile 5-7-membered cycles. However, examples asymmetric are quite scarce, have to rely on use chiral organocatalysts, been limited pentadienyl-anion- triene-type electrocyclizations. Described herein is a zinc-catalyzed formal [4+3] annulation isoxazoles with 3-en-1-ynol ethers via electrocyclization, leading site-selective functionalized 2H-azepines 4H-azepines good excellent yields broad substrate scope. Moreover, this strategy also used produce enantioselectivities (up 97:3 e.r.). This protocol not only first heptatrienyl-cation-type but reaction alkynes catalysis based ynol ethers.

Language: Английский

Citations

52
Palladium‐Catalyzed Asymmetric [4+3]‐Cyclization Reaction of Fused 1‐Azadienes with Amino‐trimethylenemethanes: Highly Stereoselective Construction of Chiral Fused Azepines DOI

Prathibha Kumari,

Weiwei Liu, Chengjie Wang

et al.

Chinese Journal of Chemistry, Journal Year: 2019, Volume and Issue: 38(2), P. 151 - 157

Published: Nov. 20, 2019

Summary of main observation and conclusion A Pd‐catalyzed asymmetric aromative [4+3]‐cyclization reaction amino‐trimethylenemethanes (TMM, 1,3‐dipoles) with fused 1‐azadienes has been developed. This method enables access to the synthetically importance biologically active benzofuran azepines indeno‐azepines in excellent efficiency stereoselectivity (up 95% yield, 99% ee, >19 : 1 dr).

Language: Английский

Citations

49
Palladium-Catalyzed Diastereo- and Enantioselective [3 + 2] Cycloaddition of Vinylcyclopropanes with Azadienes: Efficient Access to Chiral Spirocycles DOI
Kai Liu, Jianfeng Yang, Xiaoxun Li

et al.

Organic Letters, Journal Year: 2021, Volume and Issue: 23(3), P. 826 - 831

Published: Jan. 27, 2021

Benzofuran-derived azadienes (BDAs) have been widely used as four-atom synthons in transition-metal-mediated cycloaddition reactions, while the exploitation of their reactivity a two-atom unit to construct spirocycles is still underdeveloped. Herein, we reported first palladium(0)-catalyzed diastereo- and enantioselective [3 + 2] annulation vinylcyclopropanes (VCPs) BDAs. This transformation featured with broad substrate scope (31 examples), allowing for facile access variety enantioenriched bearing quaternary stereogenic center good yields excellent regio-, diastereo-, enantioselectivities (up 93% yield, >20:1 dr, mostly >99% ee) under mild reaction conditions. Moreover, spirocyclic products could be efficiently converted structurally complex tricyclo[8.3.0.01,5]-azatridecane tricyclo[7.3.0.01,5]-azadodecane skeletons.

Language: Английский

Citations

41