Use of the N–O Bonds in N-Mesyloxyamides and N-Mesyloxyimides To Gain Access to 5-Alkoxy-3,4-dialkyloxazol-2-ones and 3-Hetero-Substituted Succinimides: A Combined Experimental and Theoretical Study DOI
René Peters,

Lucca Pfitzer,

Juliane Heitkämper

et al.

Synthesis, Journal Year: 2023, Volume and Issue: 55(16), P. 2460 - 2472

Published: May 11, 2023

Abstract The reactivity of N-mesyloxyamides and -imides with bases was studied based on the initial hypothesis a possible [3,3]-rearrangement. While intended α-sulfonyloxylation method could not be developed, formation valuable N-containing heterocyclic products found. Treating triethylamine gave fully substituted oxazolone products, which are masked α-amino acid derivatives. were identified by computational approach, revealed that α-lactams first formed from an enolate intramolecular nucleophilic substitution. As strained intermediates, they readily rearrange to products. With cyclic N-mesyloxyimide, elimination maleimide This might indicate sulfonyloxylation has taken place, but corresponding product probably underwent elimination. Nucleophiles then added trap this suspected intermediate substitution methanesulfonate. That way, quaternary α-nitrogen- α-oxygen-substituted succinimides formed, represent pharmacologically important class received much attention for its value in drug design.

Language: Английский

Palladium-Catalyzed Regioselective C3-Allylic Alkylation of 2-Aryl Imidazopyridines with MBH Carbonates DOI

Tamilarasu Murugesan,

Afna Elikkottil,

Kaliyamoorthy Alagiri

et al.

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(4), P. 2655 - 2665

Published: Jan. 31, 2023

Imidazopyridine is an important framework that constitutes several pharmaceutical drugs and biologically active molecules. Herein, we present the palladium-catalyzed regioselective C3-allylic alkylation of 2-aryl imidazopyridines with MBH carbonates. This strategy furnishes a broad spectrum C3-allylated imidazopyridines, their structures have been unequivocally established using X-ray analysis. Besides, reaction can be easily scaled up on gram scale, ensuing product smoothly manipulated into synthetically useful entities.

Language: Английский

Citations

8
Enantioselective construction of quaternary stereocenters via organocatalytic arylation of isoxazolin-5-ones with o-quinone diimides DOI Creative Commons
Ricardo Torán,

Eduardo Portillo,

Amparo Sanz‐Marco

et al.

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(24), P. 6081 - 6086

Published: Jan. 1, 2023

A bifunctional squaramide catalyzes the enantioselective arylation of isoxazolin-5-ones with o -quinone diimides ( -QDIs) to give featuring an arylated quaternary stereocenter in high yields and excellent enantioselectivities.

Language: Английский

Citations

4
Stereoretentive Regio‐ and Enantioselective Allylation of Isoxazolinones by a Planar Chiral Palladacycle Catalyst DOI Creative Commons
Xin Yu,

Lingfei Hu,

Wolfgang Frey

et al.

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(42)

Published: July 28, 2022

The catalytic allylic substitution is one of the most important tools in asymmetric synthesis to form C-C bonds an enantioselective way. While high efficiency was previously accomplished terms enantio- and regiocontrol using different catalyst types, a strong general limitation very pronounced preference for formation products with (E)-configured C=C double bonds. Herein, we report that planar chiral palladacycle diastereospecific reaction outcome achieved isoxazolinones imidates as substrates, thus maintaining bond geometry substrates highly enantioenriched products. DFT calculations show reactions proceed via S

Language: Английский

Citations

7
A theoretical study of the mechanisms, regio- and enantioselectivities associated with rhodium-catalyzed allylic alkylation reactions using hard benzylzinc nucleophiles DOI
Hui Chen,

Yupan Li,

Haiyi Chen

et al.

Molecular Catalysis, Journal Year: 2023, Volume and Issue: 545, P. 113211 - 113211

Published: May 3, 2023

Language: Английский

Citations

2
Organocatalytic Desymmetric Spirocyclization of Enone-Tethered 2,5-Cyclohexadienone with Isoxazolines to Access Enantioenriched Spiro-Fused Scaffolds DOI
Sachin S. Gorad, Prasanta Ghorai

Organic Letters, Journal Year: 2024, Volume and Issue: 26(41), P. 8780 - 8785

Published: Oct. 7, 2024

Enantioselective desymmetric spirocyclization is a powerful tool for concisely generating intricate 3D molecular architectures from readily accessible substrates. Herein, we report an organocatalytic of enone-tethered 2,5-cyclohexadienone with 3-arylisoxazol-5(4

Language: Английский

Citations

0
Planar Chiral Ferrocendiyl and Ruthenocendiyl Bisimidazoline Bispalladacycles Featuring Pyridin‐2‐olates and Ketophenolates as Potentially Hemilabile Ligands in Asymmetric 1,4‐Additions DOI Creative Commons

Konstantin Dorst,

Wolfgang Frey, René Peters

et al.

European Journal of Inorganic Chemistry, Journal Year: 2024, Volume and Issue: 27(12)

Published: Jan. 31, 2024

Abstract Planar chiral bispalladacycles based on ferrocene have previously been shown to be excellent catalysts for asymmetric 1,4‐additions of α‐cyanoacetates enones. For a bimetallic reaction pathway, it was found that product decomplexation is probably rate‐determining as result two‐point binding. We hypothesized the use hemilabile chelating ligands might accelerate this step improve catalytic activity. Here we report pyridin‐2‐olates (pyridonates) potentially 1,3‐ N , O ‐chelating in application. In article, describe first coordination pyridonate planar chiral, metallocene palladacycles. Four resulting and ruthenocene bis‐palladium complexes were characterized by X‐ray single crystal structure analysis revealing μ 2 ‐( ) mode. suggest an observed lower efficiency new has its origin particular reason, related trifluoromethylketophenolate ligand installed which κ expected also experimentally found. Indeed, case activity improved compared benchmark system.

Language: Английский

Citations

0
Use of the N–O Bonds in N-Mesyloxyamides and N-Mesyloxyimides To Gain Access to 5-Alkoxy-3,4-dialkyloxazol-2-ones and 3-Hetero-Substituted Succinimides: A Combined Experimental and Theoretical Study DOI
René Peters,

Lucca Pfitzer,

Juliane Heitkämper

et al.

Synthesis, Journal Year: 2023, Volume and Issue: 55(16), P. 2460 - 2472

Published: May 11, 2023

Abstract The reactivity of N-mesyloxyamides and -imides with bases was studied based on the initial hypothesis a possible [3,3]-rearrangement. While intended α-sulfonyloxylation method could not be developed, formation valuable N-containing heterocyclic products found. Treating triethylamine gave fully substituted oxazolone products, which are masked α-amino acid derivatives. were identified by computational approach, revealed that α-lactams first formed from an enolate intramolecular nucleophilic substitution. As strained intermediates, they readily rearrange to products. With cyclic N-mesyloxyimide, elimination maleimide This might indicate sulfonyloxylation has taken place, but corresponding product probably underwent elimination. Nucleophiles then added trap this suspected intermediate substitution methanesulfonate. That way, quaternary α-nitrogen- α-oxygen-substituted succinimides formed, represent pharmacologically important class received much attention for its value in drug design.

Language: Английский

Citations

0