Facile Synthesis of 1,4,2‐Dioxazines Using Aromatic Chlorooximes and 2‐Chloroethanol/2‐Chlorophenols DOI

Lavina Gladis Serrao,

Mahagundappa Rachappa Maddani

Asian Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 16, 2024

Abstract A facile and mild strategy for the synthesis of 5,6‐dihydro‐1,4,2‐dioxazines by reaction aromatic chlorooximes with 2‐chloroethanol in presence NaH at room temperature a short period time is developed. This further extended substituted 1,4,2‐dioxazines using 2‐chlorophenols. Similarly, 5,6‐dihydro‐1,4,2‐dioxazepine was also synthesized chlorooxime 3‐bromopropanol. The developed protocol simple, efficient produces environmentally benign byproducts.

Language: Английский

Synthesis of Chiral Endocyclic Allenes and Alkynes via Pd-Catalyzed Asymmetric Higher-Order Dipolar Cycloaddition DOI

Bin Shi,

Meng Xiao,

Jin-Pu Zhao

et al.

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 18, 2024

A Pd-catalyzed asymmetric higher-order dipolar cycloaddition between allenyl carbonates and azadienes is achieved by exploiting novel alkylidene-π-allyl-Pd dipoles. This research provides a modular platform for the synthesis of challenging chiral endocyclic allenes bearing medium-sized heterocyclic motif centrally stereocenter in good yields with high enantio- diastereoselectivities (29 examples, up to 97% yield, 97:3 er >19:1 dr). Experimental computational studies elucidate possible reaction mechanism observed stereochemical results. Based on mechanistic understanding, new π-propargyl-Pd dipole was designed further extend success higher order strategy 10-membered alkynes from propargyl (13 98% yield 94.5:5.5 er).

Language: Английский

Citations

11
Palladium-Catalyzed Allylic Alkylation Reactions of Nucleophilic Allenones: Asymmetric Allylic Alkylation, Z/E Divergent Allylic Alkylation, and [5 + 2] Annulation DOI
Wang Wang, Yimin Hu, Kuan Li

et al.

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(13), P. 9940 - 9954

Published: June 19, 2024

Metal-catalyzed allenylic substitution reactions where allenes serve as electrophilic precursors have been recognized a rapid way for novel allene construction. On the contrary, chemistry in which act nucleophiles has far less investigated, especially powerful platform such metal-catalyzed allylic alkylation reactions. We herein describe two unprecedented palladium-catalyzed of an nucleophile. In first reaction, using vinyloxazolidinones allyl precursor, asymmetric allylation trisubstituted allenones worked well to prepare array axially chiral tetrasubstituted allenes. Mechanistic studies and density functional theory (DFT) calculations indicated that weak hydrogen-bonding interaction between acidic C(sp2)–H allenone nitrogen anion π-azaallyl-Pd species is key success stereocontrol. This reaction revealed intriguing reactivity nucleophilic time. second with use allenylethylene carbonates π-oxyallyl-Pd precursors, presented unique under different conditions provide divergent synthetic access (E)- (Z)-allenyl diene products. Interestingly, subsequent sequential intramolecular cyclization/isomerization (Z)-product delivered dihydrooxepine derivatives [5 + 2] annulation

Language: Английский

Citations

10
4-Vinylbenzodioxinones as a new type of precursor for palladium-catalyzed (4+3) cycloaddition of azomethine imines DOI
Yi Tang,

Rulei Zhang,

Yujie Dong

et al.

Chemical Communications, Journal Year: 2024, Volume and Issue: 60(11), P. 1436 - 1439

Published: Jan. 1, 2024

Benzo-fused cyclic carbonates were designed and synthesized as a novel type of precursor π-allylpalladium zwitterionic intermediates.

Language: Английский

Citations

8
Palladium-Catalyzed Asymmetric (3 + 2) Cycloaddition of 5-Allenyloxazolidine-2,4-Diones with Barbiturate-Derived Alkenes: Synthesis of Spirobarbiturate-γ-Lactams DOI
Yujie Dong, Jun Liu, Kuan Li

et al.

Organic Letters, Journal Year: 2023, Volume and Issue: 25(34), P. 6328 - 6333

Published: Aug. 23, 2023

The 5-allenyloxazolidine-2,4-diones had been synthesized as novel precursors of π-allyl palladium zwitterion and were applied in a palladium-catalyzed enantioselective (3 + 2) annulation by using barbiturate-derived alkenes the reaction partner presence an axially chiral phosphoramidite ligand. This proceeded smoothly under mild conditions, affording highly functionalized spirobarbiturate-γ-lactam derivatives excellent yields along with high diastereo- enantioselectivities. scale-up further transformation product also successful.

Language: Английский

Citations

12
Recent Advances in Decarboxylative Conversions of Cyclic Carbonates and Beyond DOI
Wusheng Guo,

Biwei Yan

Synthesis, Journal Year: 2021, Volume and Issue: 54(08), P. 1964 - 1976

Published: Dec. 7, 2021

Abstract In recent years, functionalized cyclic organic carbonates have emerged as valuable building blocks for the construction of interesting and useful molecules upon decarboxylation under transition-metal catalysis. By employing suitable catalytic systems, development chemo-, regio-, stereo- enantioselective methods synthesis compounds has advanced greatly. On basis previous research on this topic, short review highlights synthetic potential catalysis over last two years. 1 Introduction 2 Transition-Metal-Catalyzed Decarboxylation Vinyl Cyclic Carbonates 3 Zwitterionic Enolate Chemistry Based Transition-Metal Catalysis 4 Alkynyl Dioxazolones 5 Conclusions Perspectives

Language: Английский

Citations

25
Palladium-Catalyzed Asymmetric Cascade Intramolecular Cyclization/Intermolecular Michael Addition Reaction of Allenyl Benzoxazinones with 1-Azadienes DOI

Huawei Lin,

Xianru Yang,

Wenyue Ning

et al.

Organic Letters, Journal Year: 2022, Volume and Issue: 24(51), P. 9442 - 9446

Published: Dec. 20, 2022

We herein designed and synthesized allenyl benzoxazinones of a novel type, which were then involved in Pd-catalyzed asymmetric cascade intramolecular cyclization/intermolecular Michael addition reaction with 1-azadienes. A broad range chiral C2-functionalized quinoline derivatives afforded moderate to good yields (up 93%) high enantioselectivities 93% ee) this reaction.

Language: Английский

Citations

16
Pd-catalyzed cascade cyclization of allenylethylene carbonates and indandiones: Synthesis of tetracyclic dihydrocyclopentaindenofuranone derivatives DOI
Yujie Dong, Jun Liu, Xing Gao

et al.

Chinese Chemical Letters, Journal Year: 2023, Volume and Issue: 34(10), P. 108297 - 108297

Published: March 6, 2023

Language: Английский

Citations

9
Pyrazolidinone-Aided Ru(II)-Catalyzed Regioselective C–H Annulation with Allenes DOI
Geetanjali S. Sontakke, Atul Chaturvedi,

Debasish Jana

et al.

Organic Letters, Journal Year: 2024, Volume and Issue: 26(21), P. 4480 - 4485

Published: May 20, 2024

Regioselective annulation of allenes via C–H activation represents an elegant synthetic approach toward the construction valuable scaffolds. Considering importance allenes, herein we developed unprecedented Ru(II)-catalyzed highly regioselective redox-neutral activation/(4 + 1)-annulation 1-arylpyrazolidinones employing allenyl acetates to access pyrazolo[1,2-a]indazol-1-one derivatives. Additionally, cyclic carbonates, which were never tested in activation, utilized construct a similar class heterocycles having pendent alcohol functionality. Notably, double functionalization was achieved by simple modification reaction conditions. The significance this methodology is underscored late-stage natural products, broad substrate scope, gram-scale synthesis, and postfunctionalizations.

Language: Английский

Citations

3
Palladium-Catalyzed (4 + 1) Annulation of 4-Vinylbenzodioxinones with Sulfur Ylides: Diastereoselective Synthesis of Dihydrobenzofuran Derivatives DOI
Yi Tang, Xiaojing Sun,

Yu Tan

et al.

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(12), P. 8951 - 8959

Published: May 30, 2024

Palladium-catalyzed (4 + 1) annulation of 4-vinylbenzodioxinones with sulfur ylides has been developed to afford various dihydrobenzofuran derivatives in moderate high yields excellent diastereoselectivities. The scale-up reaction and further derivations the product worked well, demonstrating application potential current organic synthesis.

Language: Английский

Citations

2
Ni-Catalyzed Asymmetric Decarboxylation for the Construction of Carbocycles with Contiguous Quaternary Carbon Stereocenters DOI Creative Commons

Yicheng He,

Biwei Yan,

Cheng Ma

et al.

Chemical Science, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 26, 2024

The first Ni-catalyzed asymmetric decarboxylative strategy for the construction of carbocycles with contiguous quaternary all-carbon stereocenters is reported. key to success these reactions utilization rationally designed allenylic methylene cyclic carbonates as substrates Ni catalysis. floppy group exerts unique electronic properties on carbonate, which allows further nucleophilic annulations alkenes. These can be performed at room temperature and feature wide functional tolerance excellent induction that typically >94% ee. mechanistic insights imply this conceptually new chemistry completely different from previous reports catalytic transformation carbonates, thus, it offers an inventive novel methodology create complex enantio-enriched molecules.

Language: Английский

Citations

2