Oxidative [3+2] Annulation of Pyridinium Salts with gem‐Difluoroalkenes: Synthesis of 2‐Fluoroindolizines DOI

Li‐Miao Yang,

You‐Ya Zhang,

Jing‐Tong Deng

et al.

Asian Journal of Organic Chemistry, Journal Year: 2021, Volume and Issue: 10(7), P. 1679 - 1682

Published: April 9, 2021

Abstract An oxidative [3+2] annulation of pyridinium salts with gem ‐difluoroalkenes for the synthesis highly substituted 2‐fluoroindolizines has been developed. Using DBU as base, a broad range multisubstituted were prepared in good to excellent yields under mild conditions, and many useful functional groups can be tolerated.

Language: Английский

Cascade asymmetric dearomative cyclization reactions via transition-metal-catalysis DOI
Yang‐Zi Liu, Hao Song, Chao Zheng

et al.

Nature Synthesis, Journal Year: 2022, Volume and Issue: 1(3), P. 203 - 216

Published: March 14, 2022

Language: Английский

Citations

78
Catalytic asymmetric preparation of pyrroloindolines: strategies and applications to total synthesis DOI
Guang‐Jian Mei, Wai Lean Koay,

Chuan Xiang Alvin Tan

et al.

Chemical Society Reviews, Journal Year: 2021, Volume and Issue: 50(10), P. 5985 - 6012

Published: Jan. 1, 2021

Pyrroloindolines are widely present in natural products. In this review, we summarize state-of-the-art of catalytic asymmetric synthesis pyrroloindolines, as well related applications to products total synthesis.

Language: Английский

Citations

78
Kinetic Resolution of Aziridines Enabled by N‐Heterocyclic Carbene/Copper Cooperative Catalysis: Carbene Dose‐Controlled Chemo‐Switchability DOI
Zijing Zhang,

Yu‐Hua Wen,

Jin Song

et al.

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 60(6), P. 3268 - 3276

Published: Oct. 26, 2020

Abstract Catalytic kinetic resolution (KR) and dynamic asymmetric transformation (DyKAT) are alternative complementary avenues to access chiral stereoisomers of both starting materials reaction products. The development highly efficient catalytic systems for kinetically controlled processes has therefore been one the linchpins in synthesis. N‐heterocyclic carbene (NHC)/copper cooperative catalysis enabled KR DyKAT racemic N ‐tosylaziridines by [3+3] annulation with isatin‐derived enals, leading enantioenriched ‐tosylaziridine derivatives (up >99 % ee ) a large library spirooxindole high structural diversity stereoselectivity >95:5 d.r., ). Mechanistic studies suggest that NHC can bind reversibly copper catalyst without compromising its activity regulate complex switch chemoselection between DyKAT.

Language: Английский

Citations

72
Dynamic Kinetic Activation of Aziridines Enables Radical-Polar Crossover (4 + 3) Cycloaddition with 1,3-Dienes DOI
Lei Wang, Panpan Zhou, Dong Xie

et al.

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 10, 2025

The cycloaddition of aziridines with unsaturated compounds is a valuable method for synthesizing nitrogen heterocycles. However, this process predominantly substrate-controlled, posing significant challenges in regulating the regioselectivity C–N bond cleavage. In study, we report nickel-catalyzed dynamic kinetic activation strategy that enables catalyst-controlled aziridines. Various types aziridines, including 2-phenyl, 2-carbonyl, 2-alkyl, and disubstituted consistently cleave their more sterically hindered bonds to generate 1,3-radical anion intermediates. These intermediates participate highly regioselective 1,4-Heck/allylic substitution cascade aromatic branched 1,3-dienes, resulting radical-polar crossover (4 + 3) produces seven-membered azepine products. This approach not only complements traditional dipolar cycloaddition, which typically act as zwitterionic 1,3-dipoles, but also introduces an unusual mode 1,3-dienes. Experimental investigations density functional theory (DFT) calculations provide insight into reaction mechanism.

Language: Английский

Citations

1
Enantioselective Dearomatization of Indoles by an Azoalkene‐Enabled (3+2) Reaction: Access to Pyrroloindolines DOI
Guang‐Jian Mei,

Xiwen Tang,

Yildiz Tasdan

et al.

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 59(2), P. 648 - 652

Published: Oct. 8, 2019

Abstract The enantioselective dearomatization of indoles by an organocatalytic (3+2) reaction has been established. makes use simple indole derivatives as substrates, and employs azoalkenes partners. A wide range pyrroloindolines containing all‐carbon quaternary stereogenic center were readily prepared in high yields with excellent enantioselectivities.

Language: Английский

Citations

75
Enantio- and diastereodivergent synthesis of fused indolizines enabled by synergistic Cu/Ir catalysis DOI Creative Commons

Bing‐Ke Zhu,

Hui Xu,

Lu Xiao

et al.

Chemical Science, Journal Year: 2023, Volume and Issue: 14(15), P. 4134 - 4142

Published: Jan. 1, 2023

Highly selective assembly of 2,3-fused indolizines was achieved via a cascade allylation/Friedel–Crafts type reaction with Cu/Ir catalysis. This protocol furnishes stereodivergent synthesis chiral bearing three stereogenic centers excellent results.

Language: Английский

Citations

19
Kinetic Resolution of trans-2,3-Aziridinyl Alcohols via Hydroxyl Directed Regio- and Enantioselective Ring Opening Reactions DOI

Zhe‐Ran Chang,

Si‐Si Du,

Cui Zhang

et al.

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(10), P. 6873 - 6878

Published: May 4, 2023

An efficient kinetic resolution of racemic trans-2,3-aziridinyl alcohols is established via zinc catalyzed ring opening reactions with various amines as the nucleophiles. The directing effect hydroxyl group and precise enantiodiscrimination by dinuclear cooperative catalyst are keys to success high regioselectivity enantioselectivity. A range enantioenriched vicinal diamines were obtained in good yields excellent ee values. To best our knowledge, this first example directed enantioselective nucleophilic 2,3-aziridinyl alcohols.

Language: Английский

Citations

18
Chiral Brønsted Acid Catalyzed Dynamic Kinetic Asymmetric Hydroamination of Racemic Allenes and Asymmetric Hydroamination of Dienes DOI

Jin‐Shun Lin,

Tao‐Tao Li,

Guan‐Yuan Jiao

et al.

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 58(21), P. 7092 - 7096

Published: March 28, 2019

The first highly efficient and practical chiral Brønsted acid catalyzed dynamic kinetic asymmetric hydroamination (DyKAH) of racemic allenes unactivated dienes with both high E/Z selectivity enantioselectivity are described herein. transformation proceeds through a new catalytic model involving reactive π-allylic carbocationic intermediate, generated from or proton transfer mediated by an activating/directing thiourea group. This method affords expedient access to structurally diverse enantioenriched, potentially bioactive alkenyl-containing aza-heterocycles bicyclic aza-heterocycles.

Language: Английский

Citations

49
Predicting the origin of selectivity in NHC-catalyzed ring opening of formylcyclopropane: a theoretical investigation DOI
Yang Wang, Yan Qiao, Yu Lan

et al.

Catalysis Science & Technology, Journal Year: 2020, Volume and Issue: 11(1), P. 332 - 337

Published: Nov. 14, 2020

Using density functional theory, we investigated the origin of selectivity in N-heterocyclic carbene (NHC)-catalyzed transformation formylcyclopropane with an alkylidene oxindole.

Language: Английский

Citations

43
Synthesis of Unprotected β‐Arylethylamines by Iron(II)‐Catalyzed 1,2‐Aminoarylation of Alkenes in Hexafluoroisopropanol DOI Creative Commons
Valentyn Pozhydaiev, Marie Vayer, Claire Fave

et al.

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 62(9)

Published: Dec. 21, 2022

β-Arylethylamines are prevalent structural motifs in molecules exhibiting biological activity. Here we report a sequential one-pot protocol for the 1,2-aminoarylation of alkenes with hydroxylammonium triflate salts and (hetero)arenes. Unlike existing methods, this reaction provides direct entry to unprotected β-arylethylamines remarkable functional group tolerance, allowing key drug-oriented groups be installed two-step process. The use hexafluoroisopropanol as solvent combination an iron(II) catalyst proved essential reaching high-value nitrogen-containing molecules.

Language: Английский

Citations

26