Mechanisms, regio- and stereoselectivities involved in NHC catalyzed dearomatizing annulation of ester with ylide: A computational study

Molecular Catalysis, Год журнала: 2024, Номер 560, С. 114146 - 114146

Опубликована: Апрель 16, 2024

Язык: Английский

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Gold trifluoromethyl complexes as efficient regioselective catalysts in alkyne hydration

Chemistry - A European Journal, Год журнала: 2024, Номер unknown

Опубликована: Июнь 26, 2024

Gold(III) complexes containing trifluoromethyl ligands are efficient catalysts in the hydration of alkynes, operating at low catalyst loadings, without additives, using environmentally friendly solvents and mild conditions (60 °C). Hydration terminal internal alkynes provides corresponding ketones quantitative yields special precautions as dry or inert atmospheres. Remarkably, asymmetric proceeds with moderate to notable regioselectivities, providing mixtures two possible isomers ratios up 90 : 10.

Язык: Английский

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Halide-Assisted Electrophilic C–H Activation in Aqueous Acid and Salt Solutions for the Synthesis of Ru(III)-Abnormal NHC Complexes

Organometallics, Год журнала: 2024, Номер 43(19), С. 2243 - 2255

Опубликована: Окт. 3, 2024

Язык: Английский

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[Au(Np^#)Cl]: highly reactive and broadly applicable Au(i)–NHC catalysts for alkyne π-activation reactions

Catalysis Science & Technology, Год журнала: 2023, Номер 13(17), С. 5131 - 5139

Опубликована: Янв. 1, 2023

We report [Au(NHC)Cl] complexes featuring IPr# ligands that hinge upon modular peralkylation of aniline. Wingtip-flexible [Au(Np#)Cl] is a broadly applicable catalyst with the reactivity outperforming [Au(IPr)Cl] and [Au(IPr*)Cl] complexes.

Язык: Английский

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IPr*^Oxa – a new class of sterically-hindered, wingtip-flexible N,C-chelating oxazole-donor N-heterocyclic carbene ligands

Dalton Transactions, Год журнала: 2023, Номер 52(38), С. 13608 - 13617

Опубликована: Янв. 1, 2023

We report a new class of sterically-unsymmetrical NHC ligands. The evaluation steric, electronic properties and coordination chemistry is described. Studies catalytic activity in Ag, Pd Rh-catalyzed reactions are presented.

Язык: Английский

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Vanadium‐catalyzed Hydration of 2‐Cyanopyrazine to Pyrazinamide with Unique Substrate Specificity

Chemistry - An Asian Journal, Год журнала: 2023, Номер 18(22)

Опубликована: Сен. 27, 2023

Pyrazinamide is an important medicine used for the treatment of tuberculosis(TB). The preparation pyrazinamide via catalytic hydration 2-cyanopyrazine great economic interest with high atomic economy. Heterogeneous non-precious transition metal-catalyzed nitriles under neutral reaction conditions would be rather attractive. Herein vanadium-nitrogen-carbon materials were fabricated and employed selective using water as both solvent reactant. 2-Cyanopyrazine could smoothly converted into to unique substrate specificity. Additives different N O atoms significantly affect due competitive adsorption/coordination in system. This work provides a new approach metal catalyzed nitriles.

Язык: Английский

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1-Butyl-3-methylimidazolium tetrafluoroborate as suitable solvent for BF₃: the case of alkyne hydration. Chemistry vs electrochemistry

Beilstein Journal of Organic Chemistry, Год журнала: 2023, Номер 19, С. 1966 - 1981

Опубликована: Дек. 28, 2023

In order to replace the expensive metal/ligand catalysts and classic toxic volatile solvents, commonly used for hydration of alkynes, reaction alkynes was studied in ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate (BMIm-BF 4 ) adding boron trifluoride diethyl etherate (BF 3 ·Et 2 O) as catalyst. Different liquids were used, varying cation or anion, identify best one, terms both efficiency reduced costs. The developed method efficaciously applied different achieving desired products with good yields. results obtained using a conventional approach (i.e., BF compared those achieved electrogenerated BMIm-BF , demonstrating possibility obtaining alkyne analogous improved yields, less hazardous precursors generate reactive species situ. particular, terminal arylalkynes, electrochemical route proved be advantageous, yielding preferentially vs aldol condensation products. Importantly, ability recycle subsequent reactions successfully demonstrated.

Язык: Английский

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Pd-NHC Catalyzed C-H Functionalization

Elsevier eBooks, Год журнала: 2024, Номер unknown

Опубликована: Янв. 1, 2024

Язык: Английский

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Synthesis and Electrochemical Study of Gold(I) Carbene Complexes

Molecules, Год журнала: 2024, Номер 29(17), С. 4081 - 4081

Опубликована: Авг. 28, 2024

In this work, we have prepared and characterized some gold compounds wearing a N-heterocyclic carbene (NHC) ligand as well alkynyl derivatives with different substituents. The study of their electrochemical behavior reveals that these complexes show an irreversible wave at potentials ranging between −2.79 −2.91 V, referenced to the ferrocenium/ferrocene pair. DFT calculations indicate reduction occurs mainly on aryl−C≡C fragment. cyclic voltammetry experiments under CO2 atmosphere increase in faradaic current compared argon atmosphere, indicating possible catalytic activity towards carbon dioxide reaction (CO2RR).

Язык: Английский

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Dipicolinate‐Ruthenium‐NHC/trpy Complexes: Pincer Ligand Induced Hemilability of Dipicolinate and Enhancement of Cytotoxic Property

European Journal of Inorganic Chemistry, Год журнала: 2024, Номер 27(33)

Опубликована: Авг. 29, 2024

Abstract A ruthenium(II) aquo complex [Ru(dipic)(PPh 3 ) 2 (OH )], ( 1 ), bearing O,N,O‐coordinated 2,6‐dipicolinate was synthesized via reaction of [Ru(PPh Cl ] with 2,6‐dipicolinic acid. Crystal structure determined. Utilizing as a synthon, three new complexes were synthesized. Reaction bidentate NHC‐ligand, viz . 1‐methyl‐3‐(2′‐pyridyl)imidazole IMe CN afforded [Ru(dipic)( )(PPh ). Similar reactions two pincer ligands, 2,6‐bis(1′‐methyl imidazolyl)pyridine CNC and 2,2′;6′,2“‐terpyridine trpy respectively yielded B Structure optimized by DFT method. Structures determined X‐ray crystallography. In both 3B the ligand found to be N,O‐coordinated one carboxy end remaining unbound metal center. Anticancer property , studied compared. Cytotoxicity against selected cancer cell lines, chronic myelogenous leukemia line (K562), hepatocellular carcinoma (HepG2) breast adenocarcinoma (MCF7), most promising. It displayed best activity K562, while it did not have any appreciable effect on its normal counterpart, human peripheral blood mononuclear cells (hPBMC). The comparative cytotoxicity studies indicated that presence C,N,C‐coordinated NHC in together free carboxylate dipic ligand, are presumably responsible for superior cytotoxic behavior.

Язык: Английский

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