Rh-Catalyzed Regio- and Enantioselective Allylic Phosphinylation

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(7), С. 2893 - 2898

Опубликована: Фев. 14, 2022

Transition-metal-catalyzed branched and enantioselective allylic substitution of monosubstituted precursors with carbon, nitrogen, oxygen, sulfur, fluoride nucleophiles has been well-established. However, such a selective carbon–phosphorus bond formation not realized probably due to the catalyst deactivation by strong coordinating nature phosphinylating reagents. Herein, we report Rh-catalyzed highly regio- synthesis phosphine oxides in presence chiral bisoxazoline-phosphine ligand. The application α-hydroxylalkylphosphine keep low concentration secondary is essential for high yields. addition diphenyl phosphoric acid was found only activate alcohols but also accelerate formation.

Язык: Английский

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Rhodium-Catalyzed Regio- and Enantioselective Allylic Amination of Racemic 1,2-Disubstituted Allylic Phosphates

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(22), С. 8255 - 8260

Опубликована: Май 24, 2021

Alkynylphosphines are rarely used as ligands in asymmetric metal catalysis. We synthesized a series of chiral bis(oxazoline)alkynylphosphine and them Rh-catalyzed highly regio- enantioselective allylic amination reactions 1,2-disubstituted phosphates. Chiral amines were up to 95% yield with >20:1 branched/linear (b/l) ratio 99% ee from racemic precursors. The sterically smaller linear alkynyl group on the P atom was key fit new requirements introduction bulky 2-R' groups.

Язык: Английский

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Enantioselective Synthesis of Medium-Sized-Ring Lactones via Iridium-Catalyzed Z-Retentive Asymmetric Allylic Substitution Reaction

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(11), С. 4770 - 4775

Опубликована: Март 10, 2022

Medium-sized rings are important structural units, but their synthesis, especially in a highly enantioselective manner, has been great challenge. Herein we report an synthesis of medium-sized-ring lactones by iridium-catalyzed Z-retentive asymmetric allylic substitution reaction. The reaction features mild conditions and broad substrate scope. Various eight- to 11-membered-ring can be afforded moderate excellent yields (up 88%) enantioselectivity 99% ee). utilization both Z-allyl precursors Ir catalyst is critical for the formation.

Язык: Английский

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Regio- and Enantioselective Allylic Cyanomethylation by Synergistic Rhodium and Silane Catalysis

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(7), С. 3897 - 3902

Опубликована: Фев. 8, 2023

Rh/silane-cocatalyzed regio- and enantioselctive allylic cyanomethylation with inert acetonitrile directly has been developed. Addition of a catalytic amount neutral silane reagent as an anion carrier is essential for the success this reaction. The synthesis mono- bis-allylation products can be switched by adjusting size substituents on silane, ligands, temperature. Chiral homoallylic nitriles could synthesized in above 20:1 branch/linear ratio, up to 98% yield >99% ee.

Язык: Английский

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Enantio- and diastereodivergent synthesis of fused indolizines enabled by synergistic Cu/Ir catalysis

Chemical Science, Год журнала: 2023, Номер 14(15), С. 4134 - 4142

Опубликована: Янв. 1, 2023

Highly selective assembly of 2,3-fused indolizines was achieved via a cascade allylation/Friedel–Crafts type reaction with Cu/Ir catalysis. This protocol furnishes stereodivergent synthesis chiral bearing three stereogenic centers excellent results.

Язык: Английский

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Evaluation of Pyrazolyl‐Indolizine Derivatives as Antimicrobial Agents: Synthesis, In vitro, In silico ADMET and Molecular Docking Studies

Chemistry & Biodiversity, Год журнала: 2024, Номер 21(8)

Опубликована: Май 28, 2024

Herein, we report analogues of s-indacene by the synthesis novel indolizine derivatives. Using chloroform as an appropriate solvent, sixteen derivatives pyrazolyl-indolizine (4--19) were prepared reaction 3-(dimethylamino)-1-(1H-pyrrol-2-yl)prop-2-en-1-one (1) with hydrazonoyl chloride (2) in presence triethylamine good to excellent yields. We used NMR spectra, IR, mass spectrometry, well elemental analyses prove chemical structures and purity synthesized compounds 4-19. Among all tested 5, 9, 13 19 had a potent antimicrobial efficiency against Bacillus subtilis, Staphylococcus aureus, Pseudomonas aerginousea, Sallmonella typhemerium, Candida albicans. Furthermore, significant increase lipid peroxidation (LPO) toward Gram-negative bacteria, aeruginosa when treated compound 9 was observed, while remarkably increased cell membrane oxidation Salmonella typhimurium. Additionally, utilized docking studies silico methods evaluate drug-likeness, physicochemical properties, ADMET profiles compounds. The results molecular simulation revealed that displayed decreased binding energy interacting active sites important enzymes, including Sterol 14-demethylase C. albicans, Dihydropteroate synthase S. LasR P. aeruginosa, Glucosamine-6-phosphate typhimurium, Gyrase B B. subtilis.

Язык: Английский

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Catalytic asymmetric conjugate addition of indolizines to unsaturated ketones catalyzed by chiral-at-metal complexes

Organic Chemistry Frontiers, Год журнала: 2022, Номер 9(7), С. 1932 - 1936

Опубликована: Янв. 1, 2022

A highly enantioselective conjugate addition of indolizine and its analogues with α,β-unsaturated 2-acyl imidazoles has been developed.

Язык: Английский

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Silver-Promoted (4 + 1) Annulation of Isocyanoacetates with Alkylpyridinium Salts: Divergent Regioselective Synthesis of 1,2-Disubstituted Indolizines

Organic Letters, Год журнала: 2021, Номер 23(19), С. 7555 - 7560

Опубликована: Сен. 15, 2021

An unprecedented silver-promoted regioselective (4 + 1) annulation of isocyanoacetates with pyridinium salts is reported. The established protocol provides controlled, facile, and modular access to a range synthetically useful N-fused heterocyclic scaffolds containing indolizines, pyrrolo[1,2-a]quinolines, pyrrolo[2,1-a]isoquinolines, 1H-imidazo[4,5-a]indolizin-2(3H)-ones. A mechanistic pathway involving nucleophilic addition/protonation/elimination/cycloisomerization proposed.

Язык: Английский

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Oxidative [3+2] Annulation of Pyridinium Salts with gem‐Difluoroalkenes: Synthesis of 2‐Fluoroindolizines

Asian Journal of Organic Chemistry, Год журнала: 2021, Номер 10(7), С. 1679 - 1682

Опубликована: Апрель 9, 2021

Abstract An oxidative [3+2] annulation of pyridinium salts with gem ‐difluoroalkenes for the synthesis highly substituted 2‐fluoroindolizines has been developed. Using DBU as base, a broad range multisubstituted were prepared in good to excellent yields under mild conditions, and many useful functional groups can be tolerated.

Язык: Английский

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Rhodium-Catalyzed Regio- and Enantioselective Allylic Sulfonylation from Sulfonyl Hydrazides

Organic Letters, Год журнала: 2023, Номер 25(20), С. 3693 - 3697

Опубликована: Май 15, 2023

A highly regio- and enantioselective allylic sulfonylation has been developed with rhodium bisoxazolinephosphine (NPN*) ligands from racemic branched carbonates readily available sulfonyl hydrazides under neutral conditions. Branch-selective sulfones a >20:1 branch:linear ratio >99% ee could be synthesized in ≤96% yield. Both Z E linear also converted into the same chiral high enantioselectivities.

Язык: Английский

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