Recent development in asymmetric organocatalytic domino reactions involving 1,6-addition as a key step

Organic Chemistry Frontiers, Год журнала: 2021, Номер 9(2), С. 572 - 592

Опубликована: Ноя. 15, 2021

This article highlights the significant development in stereoselective domino reactions involving 1,6-addition as a crucial step.

Язык: Английский

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Multicomponent Synthesis of S-Benzyl Dithiocarbamates from para-Quinone Methides and Their Biological Evaluation for the Treatment of Alzheimer’s Disease

The Journal of Organic Chemistry, Год журнала: 2022, Номер 87(10), С. 6730 - 6741

Опубликована: Май 12, 2022

Multicomponent synthesis of biologically relevant S-benzyl dithiocarbamates from para-quinone methides, amines, and carbon disulfide are described under catalyst additive-free conditions. The reactions proceeded at room temperature in a short span time with excellent yields. One the synthesized compounds, 3e showed considerable acetylcholinesterase (AChE) inhibitory (51.70 + 5.63% 20 μm) antioxidant (63.52 ± 1.15 activities.

Язык: Английский

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Asymmetric multifunctionalization of alkynes via photo-irradiated organocatalysis

Science Advances, Год журнала: 2022, Номер 8(37)

Опубликована: Сен. 14, 2022

Alkynes represent a family of pivotal and sustainable feedstocks for various industries such as pharmaceuticals, agrochemicals, materials, they are widely used important starting materials the production broad range chemical entities. Nevertheless, efficient structural elaborations alkynes in synthesis, especially asymmetric multifunctionalization alkynes, remain largely unexplored. It is thus imperative to develop new synthetic approaches, making use these richly available feedstocks, enabling their conversion value-added chiral molecules. Here, we disclose our findings on highly enantioselective by merging photochemistry phosphoric acid catalysis. Our reported one-pot protocol applicable all types alkyne substrates, incorporating three reactants fully atom-economic fashion produce optically enriched tetrasubstituted triaryl- diarylmethanes, scaffolds medicinal chemistry biological sciences.

Язык: Английский

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Recent advances in the cyclization of para-quinone methides

Tetrahedron, Год журнала: 2023, Номер 148, С. 133655 - 133655

Опубликована: Окт. 9, 2023

Язык: Английский

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Synthesis of Fluorine-Containing Multisubstituted Oxa-Spiro[4,5]cyclohexadienones via a Fluorinated Alcohol-Catalyzed One-Pot Sequential Cascade Strategy

The Journal of Organic Chemistry, Год журнала: 2024, Номер 89(5), С. 2847 - 2857

Опубликована: Фев. 16, 2024

In recent years, the application of fluorinated alcohols as solvents, cosolvents, or additives has become important in modern organic synthesis. However, their potential efficient catalysts synthesis not been well-explored. this article, we report on development a one-pot sequential cascade reaction p-quinone methides with difluoroenoxysilanes using hexafluoroisopropanol catalyst. This allows for preparation multisubstituted oxa-spiro[4,5]cyclohexadienones. By 50 mol % 1,1,1,3,3,3-Hexafluoroisopropanol (HFIP), proceeds smoothly to yield 1,6-conjugated products, which are then subjected oxidative dearomatization/hemiacetalization PhI(OAc)2. The overall process affords moderate high yields and excellent diastereoselectivities.

Язык: Английский

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Synthesis of 1,4-Dihydroquinolines and 4H-Chromenes via Organocatalytic Domino Aza/Oxa-Michael/1,6-Addition Reactions of para-Quinone Methides and Ynals

The Journal of Organic Chemistry, Год журнала: 2020, Номер 85(17), С. 11240 - 11249

Опубликована: Авг. 11, 2020

An organocatalytic domino aza/oxa-Michael/1,6-addition reaction of ortho-tosylaminophenyl or ortho-hydroxyphenyl-substituted para-quinone methides and ynals has been developed. In the presence 20 mol % morpholine, this unprecedented cascade occurs readily in good yield (up to 99%), providing a highly efficient synthetic approach synthetically valuable 1,4-dihydroquinolines 4H-chromenes.

Язык: Английский

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Palladium-Catalyzed Asymmetric (4 + 2) Annulation of γ-Methylidene-δ-valerolactones with Alkenes: Enantioselective Synthesis of Functionalized Chiral Cyclohexyl Spirooxindoles

Organic Letters, Год журнала: 2021, Номер 23(3), С. 745 - 750

Опубликована: Янв. 21, 2021

An unprecedented asymmetric catalytic (4 + 2) annulation reaction of aryl-substituted γ-methylidene-δ-valerolactones (GMDVs) with isatin-derived para-quinone methides (p-QMs) has been developed under the catalysis palladium(0) and (S,S,S)-(−)-Xyl-SKP, offering a new approach for diastereo- enantioselective synthesis chiral cyclohexadienone-fused cyclohexyl spirooxindoles. Significantly, three highly congested contiguous tetrasubstituted carbon atoms embedded in bispirocyclic skeleton, which two are vicinal quaternary stereogenic centers, forged an effective selective manner (up to 99% yield, up 95% ee, >20/1 dr). The current represents first exploration forming six-membered carbocycles chemistry both GMDVs p-QMs.

Язык: Английский

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Asymmetric Construction of Tertiary/Secondary Carbon–Phosphorus Bonds via Bifunctional Phosphonium Salt Catalyzed 1,6-Addition

ACS Catalysis, Год журнала: 2021, Номер 11(22), С. 14168 - 14180

Опубликована: Ноя. 8, 2021

The carbon–phosphorus bond engenders distinctive physicochemical properties and has significant applications in chemical science. Herein, we disclose an efficient practical catalytic protocol for the asymmetric synthesis of remote C–P bonds by a synergistic strategy stabilizing P-nucleophile chiral phosphonium salt catalyst together with activating extended π-system side group, thus leading to cascaded 1,6-addition/aromatization reaction. This provides straightforward expedient access array both tertiary secondary stereocentralized molecules high yield exciting enantioselectivities (up >99% ee). Moreover, systematic mechanistic studies, including thorough DFT calculations control experiments, provide insights into mechanism.

Язык: Английский

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HFIP-catalyzed highly diastereoselective formal [4 + 2] cyclization to synthesize difluorinated multisubstituted chromans using difluoroenoxysilanes as C2 synthons

Chinese Chemical Letters, Год журнала: 2021, Номер 33(6), С. 3007 - 3011

Опубликована: Дек. 6, 2021

Язык: Английский

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Photocatalytic Synthesis of Diarylmethyl Silanes via 1,6-Conjugate Addition of Silyl Radicals to p-Quinone Methides

The Journal of Organic Chemistry, Год журнала: 2022, Номер 87(5), С. 3567 - 3576

Опубликована: Фев. 8, 2022

A novel photocatalytic method for the preparation of diarylmethyl silanes was reported through silyl radicals addition strategy to p-QMs (p-quinone methides). This protocol could tolerate a variety functional groups affording corresponding silylation products with moderate excellent yields. The resulting be easily converted into series bioactive GPR40 agonists and useful precursors synthesis compounds possessing both quaternary carbon centers silicon substituents simple operation. plausible mechanism proposed on basis experimental results previous literature.

Язык: Английский

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