Selective construction of spiro[indoline-3,5′-pyrrolo[3,4-b]azepines] and spiro[indoline-3,3′-pyrroles] via a [4 + 3]/[3 + 2] cycloaddition reaction of α,β-unsaturated aldimines and MBH adducts of isatins

Organic Chemistry Frontiers, Journal Year: 2022, Volume and Issue: 10(2), P. 540 - 547

Published: Dec. 10, 2022

An efficient synthetic protocol for the selective construction of spiro[indoline-3,5′-pyrrolo[3,4- b ]azepines] and spiro[indoline-3,3′-pyrroles] via a cycloaddition reaction α,β-unsaturated aldimines MBH adducts isatins was successfully developed.

Language: Английский

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[2+2+2] Cycloadditions

Elsevier eBooks, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

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The new synthesis of pyrrole-fused dibenzo[b,f][1,4]oxazepine/thiazepines by the pseudo-Joullié–Ugi reactionviaan unexpected route with high chemoselectivity

Organic & Biomolecular Chemistry, Journal Year: 2023, Volume and Issue: 21(19), P. 4095 - 4108

Published: Jan. 1, 2023

A novel and unexpected route for synthesizing pyrrole-fused dibenzoxazepines/thiazepines has been designed based on a modified Ugi reaction of cyclic imines with isocyanides acetylenedicarboxylates under catalyst-free conditions. Mechanism investigation indicates that this process is carried out through the production zwitterion species (Huisgen's 1,4-dipole), which key intermediate in chemoselectivity products. This Huisgen's 1,4-dipole trapped situ variety are synthesized simple one-pot operation high yields chemoselectivity. strategy opens new reactions (pseudo-Joullié-Ugi reaction) synthesis heterocycles as special pharmaceutical scaffolds.

Language: Английский

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Using Triazolobenzodiazepine as the Cyclic Imine in Various Types of Joullié–Ugi Reactions

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(19), P. 13504 - 13519

Published: Sept. 11, 2023

The triazolobenzodiazepine as a cyclic imine was employed in variety of Joullié–Ugi reactions, and three new families unique connected to carboxamide tetrazole products were synthesized via three-component reaction the isocyanides with each species carboxylic acid/water/TMSN3 under mild conditions high yields. Furthermore, used an interesting strategy based on modified Ugi (pseudo-Joullié–Ugi reaction) imines isocyanide acetylenedicarboxylates catalyst-free for synthesis triazolobenzodiazepine-fused pyrroles. Mechanistic investigation reveals that pyrroles have been generated surprising route. Significantly, use Joullié–Ugi, azido-Joullié–Ugi, pseudo-Joullié–Ugi reactions broad scope biological scaffolds occurred mild, simple without any catalyst.

Language: Английский

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The unique reactivity of 5,6-unsubstituted 1,4-dihydropyridine in the Huisgen 1,4-diploar cycloaddition and formal [2 + 2] cycloaddition

Beilstein Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 19, P. 982 - 990

Published: June 29, 2023

The three-component reaction of isoquinolines, dialkyl acetylenedicarboxylates, and 5,6-unsubstituted 1,4-dihydropyridines in acetonitrile at room temperature afforded functionalized isoquinolino[1,2-f][1,6]naphthyridines good yields with high diastereoselectivity. More importantly, the formal [2 + 2] cycloaddition acetylenedicarboxylates refluxing gave unique 2-azabicyclo[4.2.0]octa-3,7-dienes as major products 1,3a,4,6a-tetrahydrocyclopenta[b]pyrroles minor via further rearrangement.

Language: Английский

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Construction of Spiro[benzo[a]acridine-12,4′-imidazolidine]-2′,5′-dione Derivatives via Ring-Opening and Recyclization of Isatins and C–OH Cleavage of 2-Naphthol

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(11), P. 6995 - 7005

Published: May 8, 2023

An efficient three-component reaction to access spiro[benzo[a]acridine-12,4'-imidazolidine]-2',5'-dione derivatives has been developed through the ring-opening and recyclization process of isatins dehydroxylation 2-naphthol, which is different from their conventional modes. Experimental observations suggest that p-toluenesulfonic acid key factor promotes success this synthetic strategy. The research provided a novel approach for construction spiro compounds 2-naphthol in organic synthesis.

Language: Английский

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The Molecular Diversity Scope of Meldrum's Acid in Multicomponent Reactions

ChemistrySelect, Journal Year: 2023, Volume and Issue: 8(29)

Published: Aug. 1, 2023

Abstract Multicomponent reactions (MCRs) have gained significant attention in the field of organic synthesis due to their ability efficiently construct complex molecular structures a single step. Among reagents employed MCRs, Meldrum's acid has emerged as highly versatile and valuable starting material, offering wide range diversity. This comprehensive review explores diversity scope various focusing on its unique attributes greener aspects application. possesses several remarkable features that contribute suitability key component MCRs. Its high acidity enables effective participation variety chemical reactions, while rigid structure provides stability allows for precise control reaction pathways. Furthermore, undergo both nucleophilic electrophilic attacks makes it construction diverse frameworks. low steric hindrance further enhances reactivity, facilitating efficient bond formation. By surveying literature from last five years (2018–2022), we delve into broad applications The encompasses heterocyclic compounds, highlighting significance achieving Moreover, particular emphasis is placed utilizing acid, considering growing demand environmentally friendly synthetic approaches. includes exploring solvents, milder conditions, reduced waste generation.

Language: Английский

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Intramolecular Diels‐Alder Reaction of Styrene with Phenoxy‐Acrylate for Construction of Functionalized Naphthalenes

Asian Journal of Organic Chemistry, Journal Year: 2021, Volume and Issue: 10(10), P. 2591 - 2595

Published: Aug. 24, 2021

Abstract The DABCO promoted domino reaction of 1‐(2‐hydroxyphenyl)‐3‐phenylprop‐2‐en‐1‐ones and alkyl propiolate or dialkyl but‐2‐ynedioate in toluene at high temperature resulted methyl 3‐(2‐hydroxybenzoyl)‐1‐naphthoates dimethyl 3‐(2‐hydroxybenzoyl)naphthalene‐1,2‐dicarboxylate moderate to good yields. hydroxyl group played a crucial rule the reaction. mechanism this formal [4+2] cycloaddition was believed with initially formation 3‐(2‐cinnamoylphenoxy)acrylate, intramolecular Diels‐Alder reaction, ring‐opening benzo[b]xanthene aromatization process.

Language: Английский

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Convenient Construction of Spiro[pyrazole‐4,1′‐pyrido[2,1‐a]isoquinoline] and Spiro[pyrazole‐4,4′‐pyrido[1,2‐a]quinoline] via Three‐Component Reaction

ChemistrySelect, Journal Year: 2021, Volume and Issue: 6(39), P. 10537 - 10541

Published: Oct. 15, 2021

Abstract The three‐component reaction of isoquinoline, dialkyl but‐2‐ynedioate and 4‐arylidene‐5‐methyl‐2‐phenylpyrazol‐3‐ones in acetonitrile at room temperature gave functionalized spiro[pyrazole‐4,1′‐pyrido[2,1‐ a ]isoquinolines] satisfactory yields with cis/cis ‐diastereoisomer as major product. On the other hand, similar quinoline afforded both ‐ cis/trans ‐isomeric spiro[pyrazole‐4,4′‐pyrido[1,2‐ ]quinolines] nearly comparable yields. was finished situ generation Huisgen’ 1,4‐dipole, sequential Michael addition annulation process.

Language: Английский

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Cycloaddition of Huisgen 1,4-dipoles: synthesis and rapid epimerization of functionalized spiropyrido[2,1-b][1,3]oxazine-pyrroles and related products

RSC Advances, Journal Year: 2021, Volume and Issue: 12(1), P. 578 - 587

Published: Dec. 22, 2021

1,4-Dipolar cycloaddition has emerged as a powerful tool for the synthesis of various cyclic compounds. In present work, 1H-pyrrole-2,3-diones are proposed new dipolarophiles 1,4-dipolar cycloaddition. Their [4 + 2] with dipoles generated from dimethyl acetylenedicarboxylate and pyridine was found to proceed regioselectively affording spiro[pyrido[2,1-b][1,3]oxazine-2,3'-pyrroles] diastereomeric mixtures which exist in rapid equilibrium solution. It established that this phenomenon epimerization is characteristic other similar spiropyrido[2,1-b][1,3]oxazines even related spiroquinolizines, demonstrated by investigation products previously reported, reproduced reactions.

Language: Английский

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