Recent Advances on Catalytic Enantioselective Protonation for Construction of α-Tertiary Carbonyl Compounds DOI Open Access
Weidi Cao, Xiaohua Liu

Chinese Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 43(3), P. 961 - 961

Published: Jan. 1, 2023

Catalytic enantioselective protonation (EP) is a straightforward and effective approach to construct enantioenriched carbonyl compounds containing tertiary stereocenter at its α-position, which has been widely applied in organic synthesis medicinal chemistry.This field significant advances recent decades, relevant reviews based on substrate category, catalytic system reaction type have reported successively.In this paper, new developments are updated summarized since 2019, classied into the directly asymmetric of performed enolates situ enolates, α-carbanion, or α-radical intermediates, involving variety categories, systems, activation modes, as well strategies means.It expected that these studies can inspire chemists continuously contribute further promote development chemistry, catalysis other related fields, provide facile efficient access high-value chiral molecules, including natural products their drugs, drug candidates so on.

Language: Английский

Single-Electron Oxidation-Initiated Enantioselective Hydrosulfonylation of Olefins Enabled by Photoenzymatic Catalysis DOI

Qinglong Shi,

Xiu‐Wen Kang, Zhiyong Liu

et al.

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(4), P. 2748 - 2756

Published: Jan. 12, 2024

Controlling the enantioselectivity of hydrogen atom transfer (HAT) reactions has been a long-standing synthetic challenge. While recent advances on photoenzymatic catalysis have demonstrated great potential non-natural photoenzymes, all transformations are initiated by single-electron reduction substrate, with only one notable exception. Herein, we report an oxidation-initiated enantioselective hydrosulfonylation olefins using novel mutant gluconobacter ene-reductase (GluER-W100F-W342F). Compared to known systems, our approach does not rely formation electron donor–acceptor complex between substrates and enzyme cofactor simplifies reaction system obviating addition regeneration mixture. More importantly, GluER variant exhibits high reactivity broad substrate scope. Mechanistic studies support proposed mechanism reveal that tyrosine-mediated HAT process is involved.

Language: Английский

Citations

36
Enantioselective Radical Addition to Ketones through Lewis Acid-Enabled Photoredox Catalysis DOI
Liuzhen Hou, Yuqiao Zhou, Yu Han

et al.

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(48), P. 22140 - 22149

Published: Nov. 22, 2022

Photocatalysis opens up a new window for carbonyl chemistry. Despite multitude of photochemical reactions compounds, visible light-induced catalytic asymmetric transformations remain elusive and pose formidable challenge. Accordingly, the development simple, efficient, economic systems is ideal pursuit chemists. Herein, we report an enantioselective radical photoaddition to ketones through Lewis acid-enabled photoredox catalysis wherein in situ formed chiral N,N'-dioxide/Sc(III)-ketone complex serves as temporary photocatalyst trigger single-electron transfer oxidation silanes generation nucleophilic species, including primary, secondary, tertiary alkyl radicals, giving various enantioenriched aza-heterocycle-based alcohols good excellent yields enantioselectivities. The results electron paramagnetic resonance (EPR) high-resolution mass spectrum (HRMS) measurements provided favorable evidence stereocontrolled addition process involved this reaction.

Language: Английский

Citations

52
IronIII-catalyzed asymmetric inverse-electron-demand hetero-Diels–Alder reaction of dioxopyrrolidines with simple olefins DOI Creative Commons

Tangyu Zhan,

Liang Zhou, Yuqiao Zhou

et al.

Chemical Science, Journal Year: 2024, Volume and Issue: 15(13), P. 4797 - 4803

Published: Jan. 1, 2024

A highly enantioselective [4 + 2] cycloaddition of a number simple olefins with cyclic hetero-diene dioxopyrrolidines is realized by chiral iron( iii )/ N , ′-dioxide complex catalyst.

Language: Английский

Citations

10
Sequential Modifications of Metal–Organic Layer Nodes for Highly Efficient Photocatalyzed Hydrogen Atom Transfer DOI
Haifeng Zheng, Yingjie Fan,

Abigail L. Blenko

et al.

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(18), P. 9994 - 10000

Published: May 1, 2023

Herein, we report the synthesis of a bifunctional photocatalyst, Zr-OTf-EY, through sequential modifications metal cluster nodes in metal-organic layer (MOL). With eosin Y and strong Lewis acids on nodes, Zr-OTf-EY catalyzes cross-coupling reactions between various C-H compounds electron-deficient alkenes or azodicarboxylate to afford C-C C-N coupling products, with turnover numbers up 1980. In Zr-OTf-EY-catalyzed reactions, acid sites bind increase their local concentrations electron deficiency for enhanced radical additions, while EY is stabilized by site isolation MOL long-lived catalyst hydrogen atom transfer. The proximity photostable enhances catalytic efficiency approximately 400 times over homogeneous counterpart reactions.

Language: Английский

Citations

20
Enantioselective anti-Dihalogenation of Electron-Deficient Olefin: A Triplet Halo-Radical Pylon Intermediate DOI
Dong Zhang, Maoping Pu, Zhenzhong Liu

et al.

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(8), P. 4808 - 4818

Published: Feb. 16, 2023

The textbook alkene halogenation reaction establishes straightforward access to vicinal dihaloalkanes. However, a robust catalytic method for dihalogenizing electron-deficient olefins in an enantioselective manner is still under development, and its mechanism remains controversial. Herein, we disclose efficient regio-, anti-diastereo-, dibromination, bromochlorination, dichlorination reactions of enones catalyzed by chiral N,N'-dioxide/Yb(OTf)3 complex. With the combination electrophilic halogen halide salts as halogenating agents, array homo- heterodihalogenated derivatives achieved moderate good enantioselectivities. Moreover, DFT calculations reveal that novel triplet halo-radical pylon intermediate probable accounting exclusive regio- anti-diastereoselectivity.

Language: Английский

Citations

19
Visible-Light-Promoted Enantioselective Acylation and Alkylation of Aldimines Enabled by 9-Fluorenone Electron-Shuttle Catalysis DOI
Ziwei Zhong, Hongda Wu, Xiaofan Chen

et al.

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(29), P. 20401 - 20413

Published: July 9, 2024

Chiral acyclic α-tertiary amino ketones are widely present in various natural products and pharmaceuticals; however, the direct synthesis of this pharmacophore through a robust strategy still presents significant challenges. The emerging photocatalysis provides powerful approach to construct chemical bonds that difficult form via traditional two-electron pathway. Herein, we developed visible-light-induced chiral Lewis acid-catalyzed highly enantioselective acylation/alkylation aldimines enabled by cooperative FLN (9-fluorenone) electron-shuttle catalysis radical addition. An array ketones, β-amino alcohols, amines were achieved with high yields good excellent stereocontrol (87 examples, up 84% yield, 96% ee). These can be easily transformed into valuable bioactive skeletons. Extensive control experiments, detailed mechanism studies, density functional theory calculations elucidated reaction process highlighted crucial role played FLN.

Language: Английский

Citations

7
A Type of Chiral C2-Symmetric Arylthiol Catalyst for Highly Enantioselective Anti-Markovnikov Hydroamination DOI
Lin Tang, Chaoren Shen,

Shaoyu Hao

et al.

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(23), P. 16248 - 16256

Published: May 29, 2024

The development of chiral hydrogen donor catalysts is fundamental in the expansion and innovation asymmetric organocatalyzed reactions via an enantioselective atom transfer (HAT) process. Herein, unprecedented type C2-symmetric arylthiol derived from readily available enantiomeric lactate ester was developed. With these catalysts, anti-Markovnikov alkene hydroamination–cyclization reaction established, affording a variety pharmaceutically interesting 3-substituted piperidines with moderate to high enantioselectivity. Results designed control experiments theoretical computation rationalized origin stereocontrol disclosed spatial effect moiety thiols on We believed facile synthesis, flexible tunability, effective enantioselectivity-controlling capability would shed light versatile HAT related reactions.

Language: Английский

Citations

6
Quinone-Initiated Photocatalytic Enantioselective Giese Radical Addition with Ethers, Thioethers, Amines, and Alkanes DOI
Yao Luo, Yuqiao Zhou,

Fengnan Xiao

et al.

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(16), P. 12031 - 12041

Published: July 29, 2024

Photocatalytic enantioselective Giese radical addition with inert C(sp3)–H bonds represents a highly efficient and economically favorable approach to synthesizing diverse value-added chiral molecules from abundant feedstock. Herein, we disclose quinone-initiated photocatalytic asymmetric of α-substituted acrylamides by applying simple quinones as HAT photocatalysts in combination N,N′-dioxide/praseodymium(III) catalyst. A wide array ethers, thioethers, selenide, amines, alkanes can smoothly transform into the corresponding α-aryl amide derivatives satisfactory enantioselectivities (68 examples, up 95% ee) under mild conditions. Based on spectroscopy studies control experiments, catalytic cycle was proposed, DFT calculations revealed that interaction between quinone Lewis acid essential for enantio-induction back hydrogen atom transfer process.

Language: Английский

Citations

6
A Quadruple Catalysis Enabling Intermolecular Branch‐Selective Hydroacylation of Styrenes DOI

Yunosuke Takekawa,

Masanari Nakagawa,

Kazunori Nagao

et al.

Chemistry - A European Journal, Journal Year: 2023, Volume and Issue: 29(46)

Published: June 1, 2023

Abstract A quadruple N‐heterocyclic carbene/cobalt/photoredox/Brønsted base catalysis to realize branch‐selective hydroacylation of styrenes with aromatic and aliphatic aldehydes is demonstrated. This protocol allows access branched ketones from readily available materials in an atom‐economical manner. The can transfer a formyl hydrogen as radical equivalent onto the terminal carbon alkene by controlled electron proton transfers.

Language: Английский

Citations

15
Iodine radical mediated cascade [3 + 2] carbocyclization of ene-vinylidenecyclopropanes with thiols and selenols via photoredox catalysis DOI Creative Commons
Zhe Meng, Min Shi, Yin Wei

et al.

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(5), P. 1395 - 1403

Published: Jan. 1, 2024

A iodine radical mediated cascade [3 + 2] carbocyclization of ene-vinylidenecyclopropanes with thiols and selenols to provide sulfur- or selenium-containing derivatives has been disclosed.

Language: Английский

Citations

4