NHC‐Palladium‐Catalyzed Cascade Annulation of Alkynoic Acids with Unactivated Alkenes in Ionic Liquids DOI
Jianxiao Li,

Yougui Luo,

Lihua Hu

et al.

European Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 26(7)

Published: Dec. 15, 2022

Abstract An N‐heterocyclic carbene palladium (NHC‐palladium)‐catalyzed cascade annulation of alkynoic acids with unactivated alkenes under an oxygen atmosphere in ionic liquids is described. This protocol enables facile access for the preparation diverse alkyl substituted α ‐methylene‐ γ ‐lactones moderate to good yields excellent Z/E selectivity. Moreover, liquid not only acts as green solvent, but also eco‐friendly chlorine source, thus avoiding use excess metal halides such cupric chloride. Some preliminary mechanistic studies were performed, which further revealed possible pathways this annulation.

Language: Английский

Regioselective Synthesis of Pyrrole‐Based Poly(arylenevinylene)s via Mn‐Catalyzed Hydroarylation Polyaddition DOI

K. Tsukahara,

Ryota Iwamori,

Junpei Kuwabara

et al.

Macromolecular Rapid Communications, Journal Year: 2024, Volume and Issue: 45(20)

Published: July 24, 2024

Mn-catalyzed hydroarylation polyaddition of 1-(2-pyrimidinyl)pyrrole (1a) with aromatic diynes is investigated. The use commercially available MnBr(CO)

Language: Английский

Citations

2
Site-Selective Gold-Catalyzed Alkylation of α-Aminotropones with Allenes DOI

Giulio Gallorini,

Sofia Kiriakidi,

Sara Bellini

et al.

Organic Letters, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 21, 2024

The site-selective alkylation of α-aminotropones is effectively realized via gold(I)-catalyzed electrophilic activation allenamides and allenyl ethers, yielding up to 85% in 30 examples. A dedicated combined spectroscopic computational investigation accounts for both chemo- regioselective profiles the protocol. New opportunities chemical space tropone/tropolone derivatives are identified.

Language: Английский

Citations

2
When transition-metal-catalyzed C–H activation meets allene chemistry DOI Creative Commons

Shu-Meng Deng,

Yuxuan Zhao, Chengming Wang

et al.

Tetrahedron Chem, Journal Year: 2023, Volume and Issue: 8, P. 100049 - 100049

Published: Sept. 22, 2023

Transition-metal-catalyzed allenes-involved C–H functionalizations demonstrate unique selectivity and undergo exceptional pathways due to the existence of elusive orthogonal cumulative C bonds. As a result, it allows for diverse array activation reactions, such as allylation, alkenylation, allenylation, dienylation, propargylation, annulation. In this review, we comprehensively summarize noteworthy aspects transition-metal-catalyzed involving variously substituted allenes.

Language: Английский

Citations

3
Skeletal and Mechanistic Diversity in Ir‐Catalyzed Cycloisomerizations of Allene‐Tethered Pyrroles and Indoles DOI Creative Commons
Andrés Arribas, Martín Calvelo, Alejandro Rey

et al.

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(36)

Published: June 5, 2024

Pyrroles and indoles bearing N-allenyl tethers participate in a variety of iridium-catalyzed cycloisomerization processes initiated by C-H activation step, to deliver diversity synthetically relevant azaheterocyclic products. By appropriate selection the ancillary ligand substitution pattern allene, reactions can diverge from simple intramolecular hydrocarbonations tandem involving intriguing mechanistic issues. Accordingly, wide range heterocyclic structures ranging dihydro-indolizines pyridoindoles tetrahydroindolizines, as well cyclopropane-fused tetrahydroindolizines be obtained. Moreover, using chiral ligands, these cascade carried out an enantioselective manner. DFT studies provide insights into underlying mechanisms justify observed chemo- regio- stereoselectivities.

Language: Английский

Citations

0
Skeletal and Mechanistic Diversity in Ir‐Catalyzed Cycloisomerizations of Allene‐Tethered Pyrroles and Indoles DOI Creative Commons
Andrés Arribas, Martín Calvelo, Alejandro Rey

et al.

Angewandte Chemie, Journal Year: 2024, Volume and Issue: 136(36)

Published: June 5, 2024

Abstract Pyrroles and indoles bearing N ‐allenyl tethers participate in a variety of iridium‐catalyzed cycloisomerization processes initiated by C−H activation step, to deliver diversity synthetically relevant azaheterocyclic products. By appropriate selection the ancillary ligand substitution pattern allene, reactions can diverge from simple intramolecular hydrocarbonations tandem involving intriguing mechanistic issues. Accordingly, wide range heterocyclic structures ranging dihydro‐indolizines pyridoindoles tetrahydroindolizines, as well cyclopropane‐fused tetrahydroindolizines be obtained. Moreover, using chiral ligands, these cascade carried out an enantioselective manner. DFT studies provide insights into underlying mechanisms justify observed chemo‐ regio‐ stereoselectivities.

Language: Английский

Citations

0
Transition metal-catalyzed difunctionalization reactions of unactivated pi systems DOI Open Access

Austin M. Moore

Published: Jan. 1, 2024

This dissertation presents the investigations of nickel-catalyzed intramolecular alkene carboacylation via C-N bond activation, development direct conversion oxaboranes to oxaboroles through Petasis Borono-Mannich reaction, and studies alkyne acylboration copper catalysis. Chapter II discusses unactivated alkenes activation imides tetraarylborate nucleophiles. The reaction is accomplished under mild conditions employing Ni(cod)2 PtBu3 as catalytic system resulting in up 92% yield formal product. Selective achieved with asymmetric imide substrates >20:1 site selectivity. -amino ketone products are also reported undergo reduction well sequential deprotection imine cyclocondensation generate respective 66% 2.3 dr 94% ee (major stereoisomer) 71% yield. III includes oxaborane heterocycles more desirable oxaborole counterparts Patesis reaction. In these studies, selective transfer phenyl group was 93% utilizing salicylaldehyde morpholine conditions. nature aryl further investigated using computational methods elucidate most favorable mechanistic pathway. IV introduces synthesis an organoboron platform copper-catalyzed alkynes array boron-containing that achievable. By IPrCuCl catalyst presence potassium tert-butoxide, diphenylacetylene, bis(pinacolato)diboron, benzoyl chloride generation -boryl ketones 80% Exposure or amine-based nucleophiles formation novel 74% Current limitations this stem from competing borylation bis(pinacolato)diboron acid chloride.

Language: Английский

Citations

0
Three Component Cascade Processes Involving Palladium Catalyzed Transformations/Dipolar Cycloadditions for the Synthesis of Angular Heterotriquinane Derivatives DOI
Predrag Jovanović, Miloš Jovanović, Miloš Petković

et al.

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: 366(17), P. 3564 - 3571

Published: July 5, 2024

Abstract Combining chemical reactivities of allenes and oximes created a methodology for the preparation heterocyclic triquinane‐type skeletons via cascade process constructing four bonds in single step. The initial reaction allene moiety promoted by Pd‐catalysis, affording π‐allyl Pd‐species, was followed two additional transformations ‐ nucleophilic displacement dipolar cycloaddition to furnish product highly stereoselectively moderate good yields. For be efficient, it necessary use dipolarophilic component as solvent. Intriguingly, while with cyclopentanone derived oxime progressed through whole cascade, cyclohexanone analogue stopped at nitrone stage, requiring an step yield similar type products. Some aspects studied were examined DFT.

Language: Английский

Citations

0
Stereoselective rhodium-catalyzed reaction of allenes with organoboronic reagents for diversified branched 1,3-alkadienes DOI Creative Commons
Weiyi Wang,

Shichao Hong,

Wenxiang He

et al.

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Sept. 27, 2024

Language: Английский

Citations

0
NHC‐Palladium‐Catalyzed Cascade Annulation of Alkynoic Acids with Unactivated Alkenes in Ionic Liquids DOI
Jianxiao Li,

Yougui Luo,

Lihua Hu

et al.

European Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 26(7)

Published: Dec. 15, 2022

Abstract An N‐heterocyclic carbene palladium (NHC‐palladium)‐catalyzed cascade annulation of alkynoic acids with unactivated alkenes under an oxygen atmosphere in ionic liquids is described. This protocol enables facile access for the preparation diverse alkyl substituted α ‐methylene‐ γ ‐lactones moderate to good yields excellent Z/E selectivity. Moreover, liquid not only acts as green solvent, but also eco‐friendly chlorine source, thus avoiding use excess metal halides such cupric chloride. Some preliminary mechanistic studies were performed, which further revealed possible pathways this annulation.

Language: Английский

Citations

1