Recent advances in Pd-catalyzed asymmetric cyclization reactions

Chemical Society Reviews, Journal Year: 2023, Volume and Issue: 53(2), P. 883 - 971

Published: Dec. 18, 2023

This review aims to collect advancements in enantioselective palladium-catalyzed cyclization reactions over the past eleven years, and it is organized into thirteen sections depending on different types of transformations involved.

Language: 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, Journal Year: 2024, Volume and Issue: 89(5), P. 2847 - 2857

Published: Feb. 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.

Language: Английский

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Synthesis of Carbamoyl Fluorides via a Selective Fluorinative Beckmann Fragmentation

Organic Letters, Journal Year: 2021, Volume and Issue: 23(14), P. 5394 - 5399

Published: July 1, 2021

A fluorinative Beckmann fragmentation of α-oximinoamides was devised to provide synthetically useful carbamoyl fluorides. High selectivity for over a potentially competing rearrangement observed. This protocol has distinct mechanism and thus different substrate scope compared with other synthetic methods. α-Oximinoamides derived from the readily available secondary amines, lactams, or isatins were converted into structurally diverse

Language: Английский

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Recent advances in the cyclization of para-quinone methides

Tetrahedron, Journal Year: 2023, Volume and Issue: 148, P. 133655 - 133655

Published: Oct. 9, 2023

Language: Английский

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Diastereoselective synthesis of spiro[chromane-3,3′-indolines] and spiro[chromane-3,2′-indenes] via DBU promoted formal [4 + 2]cycloaddition reaction

Green Synthesis and Catalysis, Journal Year: 2021, Volume and Issue: 3(1), P. 53 - 58

Published: Oct. 22, 2021

A new DBU-catalyzed formal [4 ​+ ​2] cycloaddition between ortho-hydroxyphenyl-substituted para-quinone methides and electron-deficient dienophiles including 3-methyleneoxindoles 2-aryldeneindene-1,3-diones was established. wide range of functionalized spiro[chromane-3,3′-indolines] spiro[chromane-3,2′-indenes] were successfully synthesized in good yields with high diastereoselectivity. The features the reaction included readily available substrates, mild conditions, convenient methodology functional group tolerance.

Language: Английский

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Green synthesis of trimetallic oxide nanoparticles and their use as an efficient catalyst for the green synthesis of quinoline and spirooxindoles: Antibacterial, cytotoxicity and anti-colon cancer effects

Inorganic Chemistry Communications, Journal Year: 2021, Volume and Issue: 133, P. 108923 - 108923

Published: Sept. 20, 2021

Language: Английский

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Metal-Free Approach for Oxa-spirocyclohexadienones through [3 + 2]/[4 + 2] ipso-Cyclization of para-Quinone Methides with Halo Alcohols

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(14), P. 9987 - 10001

Published: July 5, 2023

A facile one-pot metal-free, base-mediated formal [3 + 2] and [4 dearomative ipso-cycloaddition of para-quinone methides (p-QMs) with halo alcohols has been designed for the efficient construction 2-oxa-spirocyclohexadienones in excellent yield under mild reaction conditions. The commercial availability bases, reagents, convenient procedure makes it an attractive method ipso-cyclization.

Language: Английский

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Visible-Light-Accelerated Decarboxylative N-Allylation of γ-Methylidene-δ-valerolactones via Synergistic Pd(0)/Cu(II)/Riboflavin Catalysis

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: April 18, 2025

We report a visible-light-accelerated decarboxylative N-allylation of methylidene-δ-valerolactones via synergistic Pd(0)/Cu(II)/riboflavin catalysis. This method enables efficient coupling diverse anilines and lactones under mild conditions, achieving an up to 93% yield.

Language: Английский

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Tandem (2 + 2) Annulation/Retro-4π Electrocyclization/Imino-Nazarov Cyclization Reaction of p-Quinone Methides with Ynamides: Expeditious Construction of Functionalized Aminoindenes

Organic Letters, Journal Year: 2021, Volume and Issue: 23(15), P. 5885 - 5890

Published: July 19, 2021

A new tandem annulation of p-quinone methides (p-QMs) with ynamides is described. This cascade reaction features a unique combination (2 + 2) annulation, retro-4π electrocyclization, and imino-Nazarov cyclization, wherein vinyl (p-VQMs) as one the key intermediates have been identified chemically. Significantly, an unusual structural reconstruction p-QMs involving cleavage C5–C6 bond late-stage formation C4–C6 involved, leading to methodology development for construction functionalized aminoindenes.

Language: Английский

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Formal (3 + 4)-Annulation of Propargylic p-Quinone Methides with 2-Indolylmethanols: Synthesis of Polysubstituted Indole-Fused Oxepines

The Journal of Organic Chemistry, Journal Year: 2021, Volume and Issue: 86(11), P. 7490 - 7499

Published: May 18, 2021

A novel Brønsted acid catalyzed 1,8-addition mediated (3 + 4)-annulation of in situ generated propargylic p-quinone methides with 2-indolylmethanols is described. This method provides a convenient and mild approach to structurally interesting synthetically important polysubstituted indole-fused oxepines high yields. Moreover, as four-atom synthons the 4)-annulations under conditions have been explored for first time.

Language: Английский

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