Recent Advances in C–H Activation for the Synthesis of π-Extended Materials

ACS Materials Letters, Journal Year: 2020, Volume and Issue: 2(8), P. 951 - 974

Published: June 29, 2020

The activation of typically unreactive aromatic C–H bonds by transition-metal catalysis has been receiving increased attention from the synthetic chemistry community in recent years. Advances this area have enabled direct and site-selective modification rings without need for pre-functionalization. Accordingly, these techniques found broad application many fields, including construction extended π-systems use materials science. This review will discuss reports reactions applied toward synthesis π-extended functional materials.

Language: Английский

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Recent advances in transition-metal-catalyzed directed C–H alkenylation with maleimides

Organic & Biomolecular Chemistry, Journal Year: 2022, Volume and Issue: 20(24), P. 4837 - 4845

Published: Jan. 1, 2022

Transition-metal-catalyzed directed C-H alkenylation with maleimides has attracted much attention in recent years, as maleimide core moieties are present various natural products and pharmaceuticals. In addition, these derivatives can be readily modified into biologically important compounds including succinimides, pyrrolidines γ-lactams. The efficient chelation-assisted inert bond activation strategy provides straightforward access to a wide array of structurally diverse molecules containing units. This review describes the major progress mechanistic investigations on Heck-type reaction/cyclization organic until early 2022.

Language: Английский

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Room-Temperature Synthesis of Isoindolone Spirosuccinimides: Merger of Visible-Light Photocatalysis and Cobalt-Catalyzed C–H Activation

The Journal of Organic Chemistry, Journal Year: 2020, Volume and Issue: 85(23), P. 15287 - 15304

Published: Nov. 3, 2020

A room-temperature C–H bond functionalization of benzamides has been developed by merging a photocatalyst with cobalt catalyst for the synthesis isoindolone spirosuccinimides. The reaction proceeds in aerobic conditions and does not require any sacrificial external oxidants such as Ag(I) or Mn(III) salts. Visible light activates photocatalyst, it acts an electron-transfer reagent helps fundamental organometallic steps modulating oxidation state complex. This spirocyclization showed wide substrate scope good functional group tolerance. possible mechanism was proposed from experimental outcome, showing that activation is irreversible rate-determining step.

Language: Английский

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Pd-Catalyzed Sequential Electrophilic Cyclization/Selective C–H Annulation Cascade: Synthesis of Isoxazole-Phthalimide-Fused Poly-Heterocyclics

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(5), P. 3214 - 3225

Published: Feb. 21, 2024

Harnessing the organo-palladium intermediates generated from electrophilic cyclizations for tandem C–C bond construction is a challenging task but constitutes an excellent tool constructing complex motifs simpler substrates. We realize herein such cyclative annulation of alkynyl-oxime ethers with maleimides facile isoxazole-phthalimide hybrid through Pd(II) catalysis. This protocol features regio-selectivity in C–H selection, broad substrate scope, good functional group tolerance, and scalability. Necessary KIE & labeling studies give insight into reaction mechanism.

Language: Английский

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A Sequential Activation of Alkyne and C–H Bonds for the Tandem Cyclization and Annulation of Alkynols and Maleimides through Cooperative Sc(III) and Cp*-Free Co(II) Catalysis

Organic Letters, Journal Year: 2020, Volume and Issue: 22(14), P. 5326 - 5330

Published: July 7, 2020

[4 + 2] oxidative Diels-Alder reaction of readily available alkynols with maleimide is achieved for the rapid access pthalimide-fused multicyclic compounds. The proposed to go through a sequence Sc(OTf)3-catalyzed electrophilic cyclization, ligand exchange Cp*-free cobalt, and C-H activation followed by insertion.

Language: Английский

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Ruthenium-Catalyzed Cross Dehydrogenative Annulation of N-(7-Azaindole)benzamides with Maleimides: One-Step Access to Highly Functionalized Pyrroloisoquinoline

The Journal of Organic Chemistry, Journal Year: 2021, Volume and Issue: 86(9), P. 6551 - 6565

Published: April 26, 2021

A ruthenium(II)-catalyzed cross dehydrogenative annulation of N-(7-azaindole)benzamides with maleimides has been demonstrated. Herein, we have explored the use N-amino-7-azaindole as a new bidentate directing group for [4 + 2] annulation. This method works efficiently, affording variety pharmacologically useful 7-azaindole-based isoquinolones and showing wide functional tolerance.

Language: Английский

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Rhodium(iii)-catalyzed [5+1] annulation of 2-alkenylphenols with maleimides: access to highly functionalized spirocyclic skeletons

Chemical Communications, Journal Year: 2021, Volume and Issue: 57(66), P. 8194 - 8197

Published: Jan. 1, 2021

A new edition of [5+1] annulation reaction maleimides with 2-alkenylphenols has been discovered under a Rh(III)-catalytic system. The process leads to an efficient synthesis valued spirocyclic scaffolds bearing oxygen-containing spiro carbon in single step and shows broad substrate scope good functional group tolerance. synthetic utility exemplified by synthesizing highly functionalized 2,2-disubstituted-2H-chromene skeletons gram-scale low catalyst loading.

Language: Английский

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Michael Addition and Oxidative Cross‐Coupling Reaction of α‐Oxo Ketene Dithioacetals and Maleimides: Switchable Synthesis of 3‐Alkenyl Succinimides and Maleimides

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(18), P. 3118 - 3128

Published: July 27, 2023

Abstract Switchable synthesis of 3‐alkenyl succinimides and maleimides has been achieved via Michael addition oxidative cross‐coupling reaction α‐oxo ketene dithioacetals by switching different conditions. In the presence 30 mol% CH 3 SO H in DCE at 120 °C, occurred to afford 40–90% yields, whereas Pd(OAc) 2 DMF 20 were obtained 40–80% yields from with maleimides. The presupposition directing groups onto substrates is not required reaction. method can be extended gram scale.

Language: Английский

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Rh(III)-Catalyzed Controlled Ortho-Amidation of Arylamides with Dioxazolones Using Weakly Coordinating Native Primary Amide as the Directing Group

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(8), P. 5606 - 5618

Published: April 1, 2024

Herein, we report a controlled introduction of an amide unit at the ortho-position electron-deficient arylamide system without affording any cyclized products using user-friendly dioxazolone as amidating reagent in presence Rh(III)-catalyst. This is first where native primary has been utilized weakly coordinating group for site-selective C–N bond formation reaction. The developed protocol works under external auxiliary-free conditions with wide substrate scope.

Language: Английский

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Ru(II)‐Catalyzed C‐H alkylation of N‐Benzyltriflamide with Maleimides: Synthesis of o‐Succinimide Substituted Benzaldehydes

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: 30(45)

Published: June 12, 2024

A ruthenium-catalyzed N-benzyltriflamide assisted C-H alkylation with maleimide followed by hydrolysis of in situ generated imine has been developed for the first time. This synthetic method results efficient synthesis o-succinimide derivatives benzaldehydes. reaction involves less expensive and mild conditions shows excellent site selectivity good functional group compatibility.

Language: Английский

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