Synthesis of 2,4-Disubstituted Oxazoles by a Copper-Catalyzed [3+2] Annulation/Olefination Cascade between Amides and IIII/PV Hybrid Ylides DOI
Zhaofeng Wang, Xingchen Ye

Synlett, Journal Year: 2023, Volume and Issue: 35(10), P. 1153 - 1159

Published: Oct. 2, 2023

Abstract We report a novel and efficient method for oxazole synthesis through copper-catalyzed [3+2] annulation/olefination cascade between readily available iodonium–phosphonium hybrid ylides amides. An unprecedented α-phosphonium Cu carbenoid acts as the key intermediate. This features excellent regioselectivity with mild reaction conditions broad substrate scope. Its synthetic utility is demonstrated by its application in late-stage functionalizations rapid of chiral ligand based on an motif.

Language: Английский

Remote Catalytic C(sp3)–H Alkylation via Relayed Carbenoid Transfer upon Olefin Chain Walking DOI
Qing Wang, Jeonguk Kweon, Dongwook Kim

et al.

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(45), P. 31114 - 31123

Published: Oct. 30, 2024

Transition metal carbenes have emerged as versatile intermediates for various types of alkylations. While reactions carbene species with alkenes been extensively studied, most examples focus on cyclopropanation and allylic C-H insertion. Herein, we present the first example a catalytic strategy carbene-involved regioselective remote alkylation internal olefins by synergistically combining two iridium-mediated reactivities olefin chain walking carbenoid migratory The method, utilizing sulfoxonium ylides bench-stable robust precursor, was found to be effective series tethered alkyl chains, heteroatom substituents, complex biorelevant moieties. Combined experimental computational studies revealed that reversible iridium hydride-mediated proceeds lead terminal alkyl-Ir intermediate, which then forms final insertion, resulting in terminal-alkylated products.

Language: Английский

Citations

3
Photocatalyzed [2+1] cyclization of alkenes and silylated trifluorodiazoethanes: facile entry into (difluoromethylene)cyclopropanes DOI
Chen Suo, Yizhi Zhang, Shanshan Liu

et al.

Science China Chemistry, Journal Year: 2023, Volume and Issue: 66(11), P. 3141 - 3147

Published: July 28, 2023

Language: Английский

Citations

9
Dirhodium‐Catalyzed Enantioselective Synthesis of Difluoromethylated Cyclopropanes via Enyne Cycloisomerization DOI Creative Commons
Chuntao Wang,

Dong Zhu,

Rui Wu

et al.

Advanced Science, Journal Year: 2023, Volume and Issue: 11(7)

Published: Dec. 13, 2023

Abstract (Difluoromethylated cyclopropane represents an important motif, which is widely found in bioactive and functional molecules. Despite significant progress modern chemistry, the atom‐economic enantioselective synthesis of difluoromethylated cyclopropanes still challenging. Herein, Rh 2 (II)‐catalyzed asymmetric enyne cycloisomerization described to construct chiral derivatives with up 99% yield ee low catalyst loading (0.2 mol%), can be easily transformed into highly functionalized vicinal all‐carbon quaternary stereocenters by ozonolysis. Mechanistic studies crystal structures alkyne‐dirhodium complexes reveal that cooperative weak hydrogen bondings between substrates dirhodium may play key roles this reaction.)

Language: Английский

Citations

8
Photoinduced Copper‐Catalyzed Cross‐Coupling of Acylsilanes with Heteroarenes via Bimetallic Relay DOI Creative Commons
Long Zheng,

Ying‐Chao Li,

Yichen Wu

et al.

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

Published: Oct. 14, 2024

Abstract The transition metal‐catalyzed direct coupling reactions involving electron‐rich Fischer carbene species are largely underdeveloped and remain a big challenge. Here, reaction of azoles azine N ‐oxides is reported with copper bearing an α ‐siloxy group i, which can be in situ generated from acylsilanes catalytically under photoirradiation redox‐neutral conditions. This between Cu‐carbene hard carbanion nucleophiles may undergo bimetallic relay process, confirmed by the kinetic analysis NMR analysis. features mild conditions remarkable heterocycle compatibility. Notably, this protocol tolerates series azole or ‐oxide derivatives, including benzoxazole, benzothiazole, benzoimidazole, benzoisoxazole, oxazole, oxadiazole, triazolo[4,3 ‐a ]pyridine, purine, caffeine, pyridine ‐oxide, quinoline pyrazine pyridazine etc. synthetic value approach demonstrated efficient synthesis histamine h4 receptor ligand marketed drug carbinoxamine.

Language: Английский

Citations

3
Synthesis of Alkynyl Hydrazones from Unprotected Hydrazine and Their Reactivity as Diazo Precursors DOI
Akashdeep Sharma, Paru Jamwal,

Himani Vaid

et al.

Organic Letters, Journal Year: 2023, Volume and Issue: 25(11), P. 1889 - 1894

Published: March 10, 2023

Alkynyl hydrazones are synthesized conveniently from 2-oxo-3-butynoates and hydrazine by suppressing the susceptible formation of pyrazoles. The resultant transformed into alkynyl diazoacetates under metal-free mild oxidative conditions in excellent yields. Further, cyclopropane propargyl silane carboxylates good yields developing an unprecedented copper-catalyzed carbene transfer reaction.

Language: Английский

Citations

7
Rhodium(I)-Catalyzed O–H Insertions on O-Protected α-Diazo-β-Hydroxyesters DOI

Ophélie Montiège,

Florian Rouzier,

Jérôme Lhoste

et al.

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(5), P. 3194 - 3201

Published: Feb. 13, 2024

The X–H insertion reaction constitutes a powerful tool to create diversity through the diazo decomposition of diazocarbonyl compounds. However, until now, on α-diazo-β-aryl-β-hydroxyester scaffolds, readily prepared by aldol-type addition, remained challenge for organic chemist. We report herein first O–H insertions O-protected α-diazo-β-aryl-β-hydroxyesters, providing straightforward access wide range α,β-dioxygenated esters modulation alcohol and aryl substituent. key feature achieving this transformation is use Rh(I) catalysts, which proved be crucial favor targeted product over competing 1,2-H 1,2-Ar migration products. Overall, 32 products have been prepared, in moderate good yields, with diastereoisomeric ratio up 7.5:1 syn diastereoisomer.

Language: Английский

Citations

2
A Metal-Free Cycloaddition of α-Diazoacetates with Amino Acid-Derived NHPI Esters for the Facile Synthesis of 1,2,4-Triazoles DOI
Mingyu Luo, Qiushi Shen,

Heyi Su

et al.

Organic Letters, Journal Year: 2024, Volume and Issue: 26(26), P. 5511 - 5516

Published: June 21, 2024

1,2,4-Triazoles are privileged scaffolds for many pharmaceuticals, and methods structurally diverse compound libraries of current interest. Here we report an efficient coupling α-diazoacetates with amino acid-derived alkyl

Language: Английский

Citations

2
An Azide-Free Synthesis of Metallodiazomethanes Using Nitrous Oxide DOI Creative Commons
Robert J. Ward, Mike Jörges,

Henning Remm

et al.

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(35), P. 24602 - 24608

Published: Aug. 20, 2024

Diazo compounds are valuable reagents in synthesis but usually require the use of potentially explosive or toxic starting materials. Here, we report and isolation alkali metal diazomethanides by reaction metalated ylides with nitrous oxide, resulting a formal exchange phosphine ligand dinitrogen. The proceeds through Wittig-like mechanism via [3 + 2] cycloaddition N2O across ylide bond release oxide. diazomethanes exhibit an increased thermal stability due to stronger binding N2 compared neutral diazomethanes. This is reflected short C–N distances red-shifted N–N vibrations enables versatile applications such as for preparation transition diazomethanide complexes 1,2,3-triazoles from nitriles, diazoacetates carbon dioxide, alkynes aldehydes.

Language: Английский

Citations

2
Oxadiazolines as Photoreleasable Labels for Drug Target Identification DOI
Corentin Bon, Benedikt Goretzki, Marie Flamme

et al.

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

Published: Sept. 17, 2024

Photoaffinity labeling is a widely used technique for studying ligand-protein and protein-protein interactions. Traditional photoaffinity labels utilize nonspecific C-H bond insertion reactions mediated by highly reactive intermediate. Despite being the most labels, diazirines exhibit limited compatibility with downstream organic suffer from storage stability concerns. This study introduces oxadiazolines as innovative complementary photoactivatable addition to toolbox demonstrates their application in vitro through

Language: Английский

Citations

2
Synthesis of 9,10‐Phenanthrenes via Rh(III)‐Catalyzed [4+2] Annulation of 2‐Biphenylboronic Acids with Diazo Compounds DOI
Miaomiao Tian, Lingyun Yang, Bingxian Liu

et al.

Chinese Journal of Chemistry, Journal Year: 2023, Volume and Issue: 41(11), P. 1327 - 1332

Published: Jan. 13, 2023

Comprehensive Summary A Rh(III)‐catalyzed, transmetalation triggered C—H activation/annulation of 2‐biphenylboronic acids with diazo compounds from β‐keto esters or 1,3‐dicarboxylates has been developed, leading to the synthesis two kinds 9,10‐phenanthrenes. Notably, a rhodacyle was synthesized by treating rhodium catalyst stoichiometric amounts and pyridine, which further verified be active for catalytic system. The reactions proceeded under redox‐neutral air‐tolerant conditions produce series all‐carbon six‐membered rings high efficiency.

Language: Английский

Citations

5