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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Enantioselective Dearomatization of Indoles via SmI₂-Mediated Intermolecular Reductive Coupling with Ketones

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(18), P. 10314 - 10321

Published: April 26, 2023

Samarium diiodide (SmI2) mediated reductive coupling reactions are powerful methods for the construction of carbon-carbon bond in organic synthesis. Despite extensive development recent decades, successful examples corresponding asymmetric remained scarce, probably due to involvement highly reactive radical intermediates. In this Article, we report an enantioselective dearomatization indoles via SmI2-mediated intermolecular with ketones. The utilization samarium reductant supported by chiral tridentate aminodiol ligands allows facile synthesis indoline molecules bearing two contiguous stereogenic centers high yields (up 99%) and stereoselectivity 99:1 er >20:1 dr). Combined experimental computational investigations suggested that parallel single-electron transfer each substrate from radical-radical recombination manner, which is a unique mechanistic scenario reactions.

Language: Английский

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Enantioselective Aminative Dearomatization of Indoles via Electrophilic 1,6-Addition of p-Quinone Diimides (p-QDIs)

Organic Letters, Journal Year: 2024, Volume and Issue: 26(23), P. 4932 - 4937

Published: June 3, 2024

Herein we report the first use of p-quinone diimide for aminative dearomatization 2,3-disubstituted indoles to furnish C3 aza-quaternary chiral indolenines. This approach, which proceeds via an electrophilic 1,6-addition diimide, allows synthesis array optically active indolenines with high yields and excellent enantioselectivities. A one-pot approach same has also been established further improve synthetic accessibility this protocol.

Language: Английский

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Nickel-Catalyzed Enantioselective Dearomative Heck-Reductive Allylic Defluorination Reaction of Indoles

Organic Letters, Journal Year: 2023, Volume and Issue: 25(33), P. 6122 - 6127

Published: Aug. 14, 2023

Herein, we describe a nickel-catalyzed asymmetric dearomative aryl-difluoroallylation reaction of indoles with α-trifluoromethyl alkenes as an electrophilic coupling partner. The proceeds via cascade sequence involving Heck cyclization and reductive allylic defluorination. A series gem-difluoroallyl substituted indolines are obtained in moderate to good yields (36-77% yield) excellent enantioselectivity (up 99% ee). features broad functional group tolerance, scaled-up synthesis, late-stage diversification.

Language: Английский

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Green synthesis for diverse bioactive benzo-fused spiroindolines through DBU-catalysed post-Ugi double cyclization

Chemical Communications, Journal Year: 2024, Volume and Issue: 60(41), P. 5455 - 5458

Published: Jan. 1, 2024

A metal-free protocol utilizing DBU catalysis for post-Ugi amide-ester exchange and Conia-ene double cyclization has been successfully developed, allowing the synthesis of diverse highly functionalized benzo-fused spiroindolines with anti-cancer activities under mild conditions.

Language: Английский

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Synthesis of chiral spiro-indenes via Pd-catalyzed asymmetric (4 + 2) dipolar cyclization

Chemical Synthesis, Journal Year: 2024, Volume and Issue: 4(4)

Published: Sept. 5, 2024

Chiral indene skeletons are widely found in biologically active natural products and pharmaceutical molecules, making synthesis an ongoing research hotspot organic synthetic chemistry. However, the construction of chiral spiro -indenes bearing all-carbon quaternary stereocenters via catalytic asymmetric remains challenging due to their inherent rigidity hindrance. Herein, we present a solution this unmet challenge through palladium-catalyzed (4 + 2) dipolar cyclization by trapping π-allyl-Pd 1,4-dipoles with indene-involved ketenes generated situ from 1-diazonaphthalene-2(1H )-ones visible light-induced Wolff rearrangement. This protocol features mild reaction conditions, wide substrate scope, high enantio- diastereoselectivities [31 examples, up 86% yield, 97% enantiomer excess (ee) 19:1 diastereoisomer ratio (dr)].

Language: Английский

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Rapid access to C2-quaternary 3-methyleneindolinesviabase-mediated post-Ugi Conia-ene cyclization

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(21), P. 3099 - 3102

Published: Jan. 1, 2023

Highly efficient synthesis of diverse 2,2-disubstituted 3-methyleneindoline derivatives through a one-pot base-promoted post-Ugi 5-exo-dig "Conia-ene"-type cyclization has been disclosed. The mechanism study indicates that an intramolecular hydrogen bond may play vital role in this process. antiproliferative evaluation cancer cell lines reveals protocol provides practical use the green bioactive compound libraries.

Language: Английский

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Iodine(III)-Mediated C–C Bond Coupling to Construct Spirocyclic Indolenines of Various Ring Sizes

Organic Letters, Journal Year: 2023, Volume and Issue: 25(19), P. 3533 - 3538

Published: May 8, 2023

Herein, we report a novel iodine(III)-mediated intramolecular dearomative spirocyclization of indole derivatives to generate highly strained spirocyclobutyl, spirocyclopentyl, and spirocyclohexyl indolenines in moderate good yields. A set structurally novel, densely functionalized spiroindolenines with broad functional group compatibility was efficiently constructed this way under mild reaction conditions. Moreover, the β-enamine ester as versatile product provides great convenience for synthesis bioactive compounds related natural products.

Language: Английский

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Palladium‐Catalyzed Transient Chirality Transfer and Atroposelective C‐H Functionalization to Access Quaternary Stereocenters

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(46)

Published: Sept. 27, 2022

Although palladium-catalyzed asymmetric C-H functionalization and Heck reactions represents one of the most important synthetic strategies for construction quaternary stereocenters, developing enantioselective version PdII -catalyzed carbopalladation-initiated cascade still remains a formidable challenge. Herein, an unprecedent [3+2] annulation oxime ethers alkynes has been developed, providing both spiro nonspiro indenes bearing all-carbon stereocenters in good yields (up to 98 %) with excellent enantioselectivities >99 % ee). This is accomplished by merging atroposelective activation/double carbopalladation transient axial-to-central chirality transfer process, constituting first successful example catalytic strategy involving axially chiral styrene intermediate.

Language: Английский

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Synergistic Sc(III)/Au(I)-Catalyzed Dearomative Spiroannulation of 2-(Ethynyl)aryl Cyclopropanes with 2-Aryl Indoles

Organic Letters, Journal Year: 2022, Volume and Issue: 24(47), P. 8709 - 8713

Published: Nov. 18, 2022

The diastereoselective assembly of spiroindolenines via a synergistic scandium/gold-catalyzed dearomative spiroannulation is herein described. This protocol offers access to wide variety spiroindolenine derivatives in 86% average yield with moderate excellent diastereoselectivities (up 97:3 dr). control experimental studies lend support the bimetallic relay catalysis. Moreover, scale-up reaction and synthetic transformations product further demonstrate its utility.

Language: Английский

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