Chemoselectivity of the CuAAC/Ring Cleavage/Cyclization Reaction between Enaminones and α-Acylketenimine

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(4), P. 2190 - 2199

Published: Jan. 27, 2024

Ketenimines represent an important class of reactive species, useful synthetic intermediates, and synthons. However, in general, ketenimines preferentially undergoes nucleophilic addition reactions with hydroxyl amino groups, carbon functional groups remain a less studied subset such systems. Herein, we develop straightforward syntheses pyridin-4(1H)-imines that is achieved by cyclization reacting enaminone unit α-acylketenimine which generated from the sulfonyl azides terminal ynones situ (CuAAC/Ring cleavage reaction). The cascade process starts α-C instead group, attacking electron-deficient central ketenimine, chemoselectivity unconventional products were formed intramolecular cyclization.

Language: Английский

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Divergent Conversion of Double Isocyanides with Alkenyl Bromide to Polysubstituted Pyrroles and 4-Imino-4,5-dihydropyrrolo[3,4-b]pyrrol-6(1H)-one Derivatives by Pd-Catalyzed Tandem Cyclization Reactions

Organic Letters, Journal Year: 2022, Volume and Issue: 24(3), P. 859 - 863

Published: Jan. 12, 2022

Herein a novel and concise approach to pyrrole skeletons via Pd-catalyzed tandem cyclization reactions is investigated. The substrates for the transformation could be readily prepared by phosphoric acid-catalyzed Ugi with available starting materials. In this strategy, two isocyanides participate in sequential isocyanide insertion reactions, chemoselectivity of products regulated steric hindrance isocyanide. A plausible mechanism formation corresponding adducts proposed.

Language: Английский

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Regiodivergent C–N Coupling of Quinazolinones Controlled by the Dipole Moments of Tautomers

Organic Letters, Journal Year: 2022, Volume and Issue: 24(17), P. 3144 - 3148

Published: April 21, 2022

Herein, we report that the dipole moments of tautomers can be controlling factor for regiodivergent synthesis either 14H-quinazolino[3,2-f]phenanthridin-14-ones or 6H-quinazolino[1,2-f]phenanthridin-6-ones, selectively, from unmasked 2-([1,1′-biphenyl]-2-yl)quinazolin-4(3H)-one. An intramolecular C(sp2)–NH coupling reaction mediated by PhI(OCOOCF3)2 could lead to two different regioisomers selectively at temperatures when dielectric constants solvents like hexafluoroisopropanol and trifluoroacetic acid matched with tautomer's moments.

Language: Английский

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Pd-catalyzed imine-directed one-pot access to polysubstituted pyrrolesviatandem triple isocyanide insertion/aza-Nazarov cyclization reactions

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(13), P. 3252 - 3258

Published: Jan. 1, 2023

A novel one-pot method for synthesizing polysubstituted pyrrole derivatives via three-component reactions of alkenyl bromides, amines, and isocyanides is reported by Pd catalysis, without additional ligands, with the orderly insertion three isocyanide molecules.

Language: Английский

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Divergent Synthesis of Pentacyclic Isoindolinones Enabled by Sequential Insertion of Two Different Isocyanides and Acid Promoted Cyclization of Ketenimines

Organic Letters, Journal Year: 2023, Volume and Issue: 25(12), P. 2041 - 2046

Published: March 22, 2023

A palladium-catalyzed multicomponent reaction involving o-bromobenzaldehydes and two different isocyanides was developed to assemble series of isoindolinones with spiroindolenine or azepinoindole skeletons. This sequential insertion features mild conditions, a wide substrate scope, high efficiency. Preliminary mechanistic study indicated that the difference in steric hindrance between isocyanide components is crucial when regulating sequence, whereas ligand also played an important role during whole process.

Language: Английский

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Tunable Construction of Multisubstituted 1,3-Dienes and Allenes via a 1,4-Palladium Migration/Carbene Insertion Cascade

The Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 87(18), P. 12019 - 12035

Published: Sept. 2, 2022

Efficient palladium-catalyzed vinylic C-H alkenylation and allenylation of gem-disubstituted ethylenes with N-tosylhydrazones aryl alkyl diaryl ketones were achieved to access trisubstituted 1,3-dienes tetrasubstituted allenes, respectively. An vinyl 1,4-palladium migration/carbene insertion/β-hydride elimination sequence proceeded switch the chemo- regioselectivities give structurally diverse products. Use 2-FC6H4OH additive enables enhancement reaction efficiency through accelerating key migration process.

Language: Английский

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Synthesis of 3-sulfonylisoindolin-1-ones from olefinic amides and sodium sulfinates via electrooxidative tandem cyclization

Organic & Biomolecular Chemistry, Journal Year: 2024, Volume and Issue: 22(29), P. 5897 - 5901

Published: Jan. 1, 2024

Sulfonyl groups are motifs that widely found in biologically active compounds and drug molecules, many isolated natural products as well pharmaceuticals contain sulfonyl groups. Herein, we present the synthesis of sulfonyl-substituted isoindolones by a electrochemical oxidative radical cascade cycloaddition reaction olefinic amides with sodium sulfite under oxidant- catalyst-free conditions. Various sulfinates were compatible gave desired yields up to 99%.

Language: Английский

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C–H functionalization enabled by multiple isocyanides

Chemical Society Reviews, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

This review outlines in detail strategies for state-of-the-art synthetic routes and demonstrates various interactions from the synergistic combination of C–H functionalization with multiple isocyanides to establish complicated reactions.

Language: Английский

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Divergent isoindolinone synthesis through palladium-catalyzed isocyanide bridging C–H activation

Cell Reports Physical Science, Journal Year: 2022, Volume and Issue: 3(3), P. 100776 - 100776

Published: Feb. 16, 2022

The formation of thermodynamically accessible metallacycle is crucial to achieve site-selective C–H bond activation. Here, we report an isocyanide-bridging activation through the a five-membered palladacycle. As such, proximal in aldehyde moiety activated selectively. subsequent palladium shift and intramolecular C=N insertion construct valuable isoindolinone framework. Compared with conventional isocyanide-promoted activation, both carbon nitrogen atoms isocyanide are engaged new formations. Notably, three types isoindolinones can be obtained selectively by variations reaction conditions. Mechanistic studies shed light on pathways. Moreover, synthetic potential current methodology demonstrated providing concise routes key intermediates indoprofen, indobufen, aristolactams, lennoxamine, falipamil.

Language: Английский

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Hydrogen bond-promoted regio- and stereoselective synthesis of isoindoline derivatives through Pd-catalyzed isocyanide insertion reaction involving aziridines

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(6), P. 1775 - 1781

Published: Jan. 1, 2024

We have successfully demonstrated an efficient and practical Pd-catalyzed reaction between aziridine isocyanide, leading to the synthesis of isoindoline derivatives in moderate good yields.

Language: Английский

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