Enhancing enantioselectivity of manganese catalyst for asymmetric transfer hydrogenation of ketones through P,N,N-chelation of a cyclooctyl pyridine

Journal of Catalysis, Год журнала: 2024, Номер 437, С. 115682 - 115682

Опубликована: Июль 31, 2024

Язык: Английский

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Regio- and Stereoselective Transfer Hydrogenation of Aryloxy Group-Substituted Unsymmetrical 1,2-Diketones: Synthetic Applications and Mechanistic Studies

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(29), С. 20092 - 20106

Опубликована: Июль 15, 2024

Developing a general method that leads to the formation of different classes chiral bioactive compounds and their stereoisomers is an attractive but challenging research topic in organic synthesis. Furthermore, despite great value asymmetric transfer hydrogenation (ATH) both synthesis pharmaceutical industry, monohydrogenation unsymmetrical 1,2-diketones remains underdeveloped. Here, we report aryloxy group-assisted highly regio-, diastereo-, enantioselective ATH racemic 1,2-diketones. The work produces myriad enantioenriched dihydroxy ketones, further transformations furnish all eight diaryl triols, polyphenol, emblirol, glycerol-type natural products. Mechanistic studies calculations reveal two working modes group switching regioselectivity from more reactive carbonyl less one, potential on solving synthetic issues has been clearly demonstrated.

Язык: Английский

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Visible-light-induced meta-selective sulfonylation of pyridine via an EDA complex

Chemical Communications, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

Pyridine is a versatile structural unit found in broad spectrum of pharmaceuticals, agrochemicals, and materials. Achieving selective meta-functionalization under mild conditions remains challenging due to its inherent electronic properties. In this work, we accomplished photoinduced method for meta-selective sulfonylation pyridines, facilitated by an electron donor-acceptor (EDA) complex between iodide ions sulfonyl chlorides. The reaction proceeds via oxazino-pyridine intermediate, with chloride acting as the radical precursor. This protocol stands out mild, photocatalyst-free conditions, high C5-selectivity, good scalability, offering promising approach synthesis meta-sulfonylated pyridines.

Язык: Английский

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Design of a chiral molecular pocket in a Ni(II) complex to improve stereoselectivity in the kinetic resolution of racemic epoxides with CO2

Tetrahedron Chem, Год журнала: 2024, Номер 12, С. 100115 - 100115

Опубликована: Ноя. 28, 2024

Язык: Английский

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Catalytic Asymmetric Transfer Hydrogenation of β,γ-Unsaturated α-Diketones

Journal of the American Chemical Society, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 27, 2024

Asymmetric transfer hydrogenation (ATH) has been recognized as a highly valuable strategy that allows access to enantioenriched substances and widely applied in the industrial production of drug molecules. However, despite great success ATH ketones, efficient, regio- stereoselective on enones remains underdeveloped. Moreover, optically pure acyloins 1,2-diols are both extremely useful building blocks organic synthesis, medicinal chemistry, materials science, but concise asymmetric approaches allowing different types have scarcely discovered. We report this paper first efficient readily accessible β,γ-unsaturated α-diketones. The protocol affords four fashion. synthetic value work showcased by divergent synthesis related natural products. systematic mechanistic studies density functional theory (DFT) calculations illustrated origin reactivity divergence, revealed roles aromatic aliphatic substituents substrates, provided range unique rationales not disclosed ATH-related studies.

Язык: Английский

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P(V)-bis(amidophenolate) ligand cooperation: Stoichiometric C=O-bond cleavage in aldehydes and ketones

Chemical Communications, Год журнала: 2024, Номер 60(53), С. 6745 - 6748

Опубликована: Янв. 1, 2024

The cooperation between a geometrically constrained, highly electrophilic phosphorus(V) center, and an electronically rich tetradentate bis(amidophenolate) ligand enables the cleavage of CO bond from typical aldehydes ketones delivering iminio phosphoramidate species. amphiphilic nature these products, which is demonstrated through their reaction with Lewis acids bases, use as mild source silylium cations silanes, allowing selective reductive coupling to ethers under catalytic conditions.

Язык: Английский

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Asymmetric Hydrogenation of Ketones by Simple Alkane-Diyl-Based Ir(P,N,O) Catalysts: A Comparative Study

Molecules, Год журнала: 2024, Номер 29(16), С. 3743 - 3743

Опубликована: Авг. 7, 2024

The development of new chiral ligands with simple and modular structure represents a challenging direction in the design efficient homogeneous transition metal catalysts. Herein, we report on asymmetric hydrogenation prochiral ketones catalyzed by iridium complexes alkane-diyl-based P,N,O-type highly structure. role (i) P-N N-O backbone potentially tridentate ligands, (ii) number, position relative configuration their stereogenic elements (iii) effect NH OH subunits activity enantioselectivity catalytic reactions are studied. systematic variation ligand comparative experiments shed light different mechanistic aspects iridium-catalyzed reaction. catalysts containing central chirality provided high enantioselectivities (up to 98%

Язык: Английский

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Design of a Chiral Molecular Pocket in a Ni(Ii) Complex to Improve Stereoselectivity in the Kinetic Resolution of Racemic Epoxides with Co2

Опубликована: Янв. 1, 2024

Язык: Английский

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Synthesis and Reactivity of Palladium Complexes Bearing Phosphino-Amidinate Ligands: O–H Bond Activation by Metal–Ligand Cooperation

Organometallics, Год журнала: 2024, Номер 43(22), С. 2972 - 2980

Опубликована: Ноя. 13, 2024

Phosphine ligands bearing amidine groups were designed for the synthesis of complexes in which a metal center and cooperate. Several palladium amidinate synthesized from these ligands. The reaction with various organic molecules containing an acidic OH group gave complexes. In reaction, O–H bond was activated by metal–ligand cooperation (MLC).

Язык: Английский

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Pd/S cooperativity: from stoichiometric activation of Si−H bonds to catalytic hydrosilylation

ChemistryEurope, Год журнала: 2024, Номер 3(1)

Опубликована: Ноя. 12, 2024

Abstract With the aim to explore metal‐ligand cooperation across Pd−S linkages, we designed a quinoline‐based PNS tridentate ligand and prepared Pd(II) complexes thereof. Optimal solubility stability of dicationic complex [(PNS)Pd(II)] 2 2+ IV were achieved with B(C 6 F 5 ) 4 – as counter‐anion. It adopts thiolate‐bridged dimeric structure (PdS) core, but readily activates hydrosilanes linkage. The resulting mononuclear hydride [(PNS SiR3 )Pd(II)H] + VI was characterized by multi‐nuclear NMR spectroscopy Si−H bond coordination/activation studied computationally. Complex found efficiently catalyze hydrosilylation alkynes, internal well terminal, good stereo regioselectivity.

Язык: Английский

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