Arylation of α‐Imino Ketones and their Cyclization with Allenoates: Direct Access to Sterically Hindered Pyrroles

Asian Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 28, 2025

Abstract Herein, we report a calcium‐catalyzed, one‐pot, four‐component reaction to synthesize diversely substituted pyrroles. This atom‐economy involves sequence of reactions that proceed via in situ formation α ‐ imino ketones, Friedel‐Crafts arylation, aza‐cyclization, and aromatization the single pot. The showed broad substrate scope with good yields. We demonstrated gram‐scale synthesis post‐synthetic modifications.

Language: Английский

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δ-Acetoxy Allenoate as a 5C-Synthon in Domino-Annulation with Sulfamidate Imines: Ready Access to Coumarins

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(17), P. 12432 - 12444

Published: Aug. 21, 2023

A DMAP-catalyzed sequential benzannulation and lactonization strategy in which δ-acetoxy allenoate functions as a 5C-synthon its reaction with cyclic sulfamidate imines is reported. This platform delivers π-extended coumarin frameworks under metal-free conditions via allylic elimination followed by Mannich coupling, proton shifts, C-N bond cleavage, key steps. The driving force for this domino the formation of diene-ammonium intermediate O-S cleavage. ESI-HRMS has been useful gaining insights into pathway.

Language: Английский

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Tertiary‐Amine Controlled (3+3) or (4+2) Annulations of β′‐Acetoxy Allenoates with N‐Sulfonyl Ketimines: An Entry to m‐Teraryl and Fused Dihydropyridines

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: 366(5), P. 1165 - 1175

Published: Jan. 10, 2024

Abstract Lewis base dependent (3+3) and (4+2) annulations of β′ ‐acetoxy allenoates with N ‐sulfonyl ketimines offer m ‐teraryl fused dihydropyridines varying substituents depending on the tertiary amine as well subtle changes in reaction conditions. The triazabicyclodecene (TBD)‐catalyzed annulation involves 1,2‐elimination followed by 6‐ endo ‐dig cyclization key steps delivering 1,4‐hydropyridines. same reactants under DMAP catalysis via Mannich coupling, rather than C−N bond cleavage/aromatization. Key intermediates have been identified HRMS studies.

Language: Английский

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Indium‐Catalyzed Direct Amidation Reaction of Carboxylic Acids and In Silico Study for Screening the Activity of Potential Therapeutics of the Synthesized Products

ChemistrySelect, Journal Year: 2024, Volume and Issue: 9(37)

Published: Oct. 1, 2024

Abstract Amide bonds are ubiquitous and valuable motifs in synthetic chemistry, found a wide range of applications such as the backbone proteins pharmaceutical agents. Thus, environmentally friendly selective methods for synthesizing amide important. Herein, we report simple, efficient, rapid route to access functionalized amides from non‐activated carboxylic acids amines using indium (III) trifluoromethanesulfonate an efficient catalyst. A – including aliphatic, aromatic, heterocyclic, dicarbonyl participate smoothly these reactions, generating structurally diverse moderate good yields (up 91 % 24 examples). The reactions conducted dry tetrahydrofuran (THF) under reflux conditions. Furthermore, this amidation strategy provides method addressing challenging molecules, protected amino acids, produce biocompatible products. These products can then be used substrates various organic transformations, C−H functionalization reactions. We also demonstrate utility our protocol through synthesis essential medicinal chemistry by reacting N ‐protected with 8‐aminoquinoline series biologically compounds. Five products, named 4 f, 4p, 9a, 9c, 9d, have been evaluated in‐silico study. interaction compounds receptor protein 8DQT was examined assess their potential drug candidates hypertension treatment. Effective binding detected between receptor. Data molecular docking studies show that 4d m most active, scores −8.8 −8.6 kcal/mol, respectively. However, compound exhibited stronger affinity than over course dynamic simulation. Our ADMET study suggests all five highly safe body. Based on BOILED‐Egg model study, absorption is suggested they cross blood‐brain barrier.

Language: Английский

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Acetoxy allenoates as emerging synthons in annulation/cycloaddition reactions

Chemical Communications, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

The emergence of acetoxy allenoates as versatile synthons to generate a plethora annulation/cycloaddition products via electrophilic diene–phosphonium/ammonium intermediates is highlighted in this feature article.

Language: Английский

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Phosphine-catalyzed [5+1] annulation of β′-acetoxy allenoates: straightforward access to tetrahydroquinoline derivatives

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(78), P. 11712 - 11715

Published: Jan. 1, 2023

An unprecedented phosphine-catalyzed [5+1] annulation of β'-acetoxy allenoates with 1,5-dinucleophiles has been developed, which provides novel and facile access to functionalized tetrahydroquinolines in good high yields the presence PPh3 K3PO4 under mild reaction conditions. Notably, it is first report acting as C1 synthons Lewis base-catalyzed reactions.

Language: Английский

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Synthesis of Multisubstituted 2,3-Allenamides via Palladium-Catalyzed Carbonylation of Propargylic Esters

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(12), P. 9001 - 9010

Published: June 6, 2024

2,3-Allenamides are an important class of unsaturated group-substituted carbonyl compounds. A palladium-catalyzed aminocarbonylation propargyl acetates with amines for the synthesized tri-/tetrasubstituted 2,3-allenamides has been developed. broad range have prepared from in good to excellent yields. The reaction featured mild conditions and functional group tolerance. applicability this methodology was further highlighted by late-stage modification several natural products pharmaceuticals.

Language: Английский

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Synthesis of Isoxazol-5(2H)-one Derivatives via (^tBuO)₂Mg Promoted [3 + 2] Annulations of δ-Acetoxy Allenoates with Hydroxylamine

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(11), P. 8291 - 8298

Published: May 28, 2024

Herein, an efficient (

Language: Английский

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Phosphine vs DBU-Catalyzed Annulation Reactions of β′-Acetoxy Allenoates with Acyl-Tethered Benzothiazole Bisnucleophiles: (4 + 3) or (4 + 1) vs (3 + 3) Annulation

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(15), P. 10816 - 10830

Published: July 15, 2024

Dearomative annulation reaction of acyl-tethered benzothiazole bisnucleophiles with β'-acetoxy allenoates by switching the Lewis base is developed. The DBU-catalyzed gives benzothiazole-fused 1,4-dihydropyridine carboxylates (3 + 3) chemoselectively. By contrast, PR

Language: Английский

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Decomposition of Alkynyl Hydrazones: Synthesis of Allenoates, Dihaloallenoates, and Angularly Fused Tricyclic Azepines

Organic Letters, Journal Year: 2023, Volume and Issue: 25(36), P. 6607 - 6612

Published: Sept. 5, 2023

An unprecedented decomposition of unprotected alkynyl hydrazones is attempted that has provided allenoates, tetrasubstituted α,γ-dihaloallenoates, and functionalized tricyclic azepines. A reaction with N-halosuccinimides captures the electrophile in 2-fold delivers fully substituted dibromo- diiodoallenoates good yields. In addition, a DABCO-promoted Wolff-Kishner reduction hydrazones, followed by isomerization, provides versatile allenoates under mild conditions. contrast, similar ambiphilic DBU furnishes completely different azepine scaffold excellent yield diastereoselectivity.

Language: Английский

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