C-H bond Activation/Arylation over Arene-Ruthenium(II)-picolinate Complexes: Synthesis, Structure and Catalytic Activity

A series of water soluble arene-ruthenium(II) complexes [(η6-arene)RuCl(κ2-L)]n+ (n = 0, 1) ([Ru]-1 – [Ru]-12) containing pyridine based N,O or N,N ligands (L1-L6) were synthesized and employed for the catalytic C-H bond activation/ arylation of 2-phenylpyridine with aryl halides in water. Efficient C-H bond activation/ arylation of a wide range of substituted 2-phenylpyridines and aryl halides were achieved to afford corresponding mono and biarylated products. Exploring the reactivity of the synthesized complexes, our investigation with ruthenium catalysts inferred that pyridine based N,O donor ligands afforded enhanced catalytic activity compared to those obtained with the iminopyridine (N,N donor) ligands. Further, mass spectrometric investigations, during the catalytic and controlled reaction conditions, evidenced the presence of the crucial cycloruthenated species {(η6-p-cymene)Ru(κ2-CN-phenylpyridine)}+ (m/z [M+] 390.0), along with a ligand coordinated species, {(η6-p-cymene)Ru(L1)(κ2-CN-phenylpyridine)}+ (m/z [M+]+Na 539.0), suggesting the important role such intermediate species in C-H bond activation reactions. Moreover, molecular structures for few of the representative complexes were also authenticated by single crystal X-ray diffraction studies.

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Halide-bridged Polymers of d10Metals with Heterocyclic Type Donor Ligands

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273314089748 ◽

2014 ◽

Vol 70 (a1) ◽

pp. C1025-C1025

Author(s):

Cara Slabbert ◽

Melanie Rademeyer

Keyword(s):

Optical Properties ◽

Self Assembly ◽

Bulk Composition ◽

Organic Ligands ◽

Donor Ligands ◽

Metal Halides ◽

X Ray Diffraction ◽

Reaction Conditions ◽

X Ray ◽

Wide Range

Molecular self-assembly of organic ligands and inorganic metal halides leads to the formation of layered nano-composite organic-inorganic hybrid materials. The formation of both ionic- and coordination hybrids is possible. Both of these materials have attracted much attention recently in the field of Crystal Engineering [1], due to the retention and combination of desired inherent properties of both constitutional moieties, which then renders these materials multifunctional with a wide range of potential technological applications. Properties attributed to the organic component include structural diversity and optical properties [2], with mechanical hardness, electronic-, magnetic- and optical properties ascribed to the inorganic component. The coordination of an organic amine functionality to a metal halide results in the formation of halide-bridged polymers coordinated to donor ligands, with reported properties including non-linear optic (NLO) behavior, magnetic properties [3] and electronic semi-conduction. Literature confirms the technological importance of these materials and identifies the need for research aiming at a fundamental understanding of factors that control the observed structural trends and to relate chemical composition and topology of these compounds to ultimately enable retrosynthesis from desired property. In this study, a range of different divalent d10metal halides are combined with different aromatic nitrogen-containing organic ligands. The effects of change in metal atom, halide atom, stoichiometry and reaction conditions on the structural trends in the crystal systems are investigated. The molecular self-assembly of the said halide-bridged polymers is initiated by simple synthetic techniques under relatively mild conditions, at the most, hydrothermal reaction conditions. Structural characterisation was done employing single crystal X-ray diffraction, while bulk composition of the samples was investigated using powder X-ray diffraction.

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Solid-state studies and antioxidant properties of the γ-cyclodextrin·fisetin inclusion compound

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.13.212 ◽

2017 ◽

Vol 13 ◽

pp. 2138-2145 ◽

Cited By ~ 3

Author(s):

Joana M Pais ◽

Maria João Barroca ◽

Maria Paula M Marques ◽

Filipe A Almeida Paz ◽

Susana S Braga

Keyword(s):

Inclusion Compound ◽

Antioxidant Properties ◽

Physicochemical Analysis ◽

Water Soluble ◽

Solid Inclusion ◽

Human Consumption ◽

X Ray Diffraction ◽

Wide Range ◽

Soluble Solid ◽

Cp Mas Nmr

Fisetin is a natural antioxidant with a wide range of nutraceutical properties, including antidiabetic, neuroprotecting, and suppression or prevention of tumors. The present work describes the preparation of a water-soluble, solid inclusion compound of fisetin with gamma-cyclodextrin (γ-CD), a cyclic oligosaccharide approved for human consumption. A detailed physicochemical analysis of the product is carried out using elemental analysis, powder X-ray diffraction (PXRD), Raman, infrared and 13C{1H} CP-MAS NMR spectroscopies, and thermal analysis (TGA) to verify fisetin inclusion and to present a hypothetical structural arrangement for the host–guest units. The antioxidant activity of the γ-CD·fisetin inclusion compound is evaluated by the DPPH assay.

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Nickel-catalyzed C–N bond activation: activated primary amines as alkylating reagents in reductive cross-coupling

Chemical Science ◽

10.1039/c9sc00783k ◽

2019 ◽

Vol 10 (16) ◽

pp. 4430-4435 ◽

Cited By ~ 45

Author(s):

Huifeng Yue ◽

Chen Zhu ◽

Li Shen ◽

Qiuyang Geng ◽

Katharina J. Hock ◽

...

Keyword(s):

Nickel Catalyst ◽

Bond Activation ◽

Cross Coupling ◽

Aryl Halides ◽

Primary Amines ◽

Pyridinium Salts ◽

Reaction Conditions ◽

Alkyl Amines ◽

Alkylating Reagents

The reductive cross coupling of pyridinium salts derived from readily available primary alkyl amines with aryl halides has been achieved under mild reaction conditions using a nickel catalyst.

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An efficient Pd–NHC catalyst system in situ generated from Na2PdCl4 and PEG-functionalized imidazolium salts for Mizoroki–Heck reactions in water

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.13.168 ◽

2017 ◽

Vol 13 ◽

pp. 1735-1744 ◽

Cited By ~ 7

Author(s):

Nan Sun ◽

Meng Chen ◽

Liqun Jin ◽

Wei Zhao ◽

Baoxiang Hu ◽

...

Keyword(s):

Catalytic Activity ◽

Imidazole Ring ◽

Catalyst System ◽

Water Soluble ◽

Imidazolium Salts ◽

Heck Reactions ◽

Imidazolium Salt ◽

Simple Method ◽

Wide Range

Three PEG-functionalized imidazolium salts L1–L3 were designed and prepared from commercially available materials via a simple method. Their corresponding water soluble Pd–NHC catalysts, in situ generated from the imidazolium salts L1–L3 and Na2PdCl4 in water, showed impressive catalytic activity for aqueous Mizoroki–Heck reactions. The kinetic study revealed that the Pd catalyst derived from the imidazolium salt L1, bearing a pyridine-2-methyl substituent at the N3 atom of the imidazole ring, showed the best catalytic activity. Under the optimal conditions, a wide range of substituted alkenes were achieved in good to excellent yields from various aryl bromides and alkenes with the catalyst TON of up to 10,000.

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Yttrium and Lithium Keto-β-Diketiminate Complexes [{2,6-Me2C6H3N=C(Me)}2CС(tert-Bu)=O]2Y(μ2-Cl)2Li(THF)2 and {[{2,6-Me2C6H3N=C(Me)}2CС(tert-Bu)=O]Li(THF)}n. Synthesis, Molecular Structures, and Catalytic Activity in ε-Caprolactone Polymerization

Russian Journal of Coordination Chemistry ◽

10.1134/s107032842102007x ◽

2021 ◽

Vol 47 (2) ◽

pp. 144-154

Author(s):

G. G. Skvortsov ◽

A. V. Cherkasov ◽

D. L. Vorozhtsov ◽

E. S. Shchegravina ◽

A. A. Trifonov

Keyword(s):

Catalytic Activity ◽

Diffraction Analysis ◽

Exchange Reaction ◽

Ring Opening ◽

Crystalline State ◽

Ring Opening Polymerization ◽

Molecular Structures ◽

Molar Ratio ◽

X Ray Diffraction ◽

X Ray

Abstract The reaction of lithium β-diketiminate [{2,6-Me2C6H3N=CMe}2CH]Li with benzophenone in toluene at 25°C affords the coordination complex [{2,6-Me2C6H3N=CMe}2CH]Li(Ph2C=O) (I). New keto-β-diketimine {2,6-Me2C6H3N=C(Me)}2CHC(tert-Bu)=O (II) is synthesized by the reaction of tert-Bu(C=O)Cl with [{2,6-Me2C6H3N=CMe}2CH]Li. The metallation of keto-β-diketimine II with n-butyllithium in THF at 0°C gives lithium keto-β-diketiminate {[{2,6-Me2C6H3N=C(Me)}2CС(tert-Bu)=O]Li(THF)}n (III). The exchange reaction of YCl3 with compound III (molar ratio 1 : 2, THF) affords the yttrium bis(keto-diketiminate) complex [{2,6-Me2C6H3N=C(Me)}2CС(tert-Bu)=O]2Y(μ2-Cl)2L-(THF)2 (IV). The molecular structures of complexes I, III, and IV are determined by X-ray diffraction analysis (CIF files CCDC nos. 2001131 (I), 2001132 (III), and 2001133 (IV)). Complex IV in the crystalline state exists as an ate complex with one LiCl molecule. Complexes I, III, and IV are catalysts of ring-opening polymerization of ε-caprolactone in toluene at 25°С.

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Interaction of 4-{[(tolyl(methane)sulphonyl)oxy]imino}cyclohexa-2,5-dien-1-ones with N-nucleophiles

Voprosy Khimii i Khimicheskoi Tekhnologii ◽

10.32434/0321-4095-2021-134-1-3-11 ◽

2021 ◽

pp. 3-11

Author(s):

A.P. Avdeenko ◽

◽

S.A. Konovalova ◽

I.Yu. Yakymenko ◽

V.M. Baumer ◽

...

Keyword(s):

Redox Potential ◽

Diffraction Data ◽

Sulfonic Acid ◽

Biological Activities ◽

X Ray Diffraction ◽

Reaction Conditions ◽

X Ray ◽

Wide Range ◽

Substituted Hydrazines ◽

Lower Basicity

Hydrazones of 1,4-benzoquinone, which have a wide range of biological activities, can be synthesized in the reactions of 4-{[(arylsulfonyl)oxy]imino}cyclohexa-2,5-diene-1-ones or N-(4-oxocyclohexa-2,5-diene-1-ylidene)arylsulfonamides with N-substituted hydrazines. In this study, the reaction of 2,6-disubstituted 4-{[(tolyl(methane)sulfonyl)oxy]imino}cyclohexa-2,5-diene-1-ones with aroylhydrazides gave N'-(3,5-dialkyl-4-oxocyclohexa-2,5-diene-1-ylidene)aroylhydrazides, which can be obtained by cross-synthesis in the reaction of N-(3,5-dialkyl-4-oxocyclohexa-2,5-dien-1-ylidene)arylsulfonamides with aroylhydrazides. As a result of the reaction of 4-{[(tolyl(methane)sulfonyl)oxy]imino}cyclohexa-2,5-dien-1-ones with phenylhydrazine, stable 4-hydroxyanilinium tolyl(methane)sulfates were isolated. Their structures were confirmed by X-ray diffraction data. We suggested that at the first stage of the reaction between 4-{[(tolyl(methane)sulfonyl)oxy]imino}cyclohexa-2,5-diene-1-ones and hydrazines, the N–O bond of starting 4-(oxyimino)cyclohexa-2,5-diene-1-one was broken forming sulfonic acid and corresponding quinoneimine. The latter either can be reduced to corresponding aminophenol under reaction conditions or can react with an excess of N-substituted hydrazine yielding corresponding hydrazide. The formation of N'-(4-oxocyclohexa-2,5-diene-1-ylidene)arohydrazides is facilitated by a lower basicity of hydrazide and a lower redox potential of quinoneimine.

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New Coordination Complexes Based on the 2,6-bis[1-(Phenylimino)ethyl] Pyridine Ligand: Effective Catalysts for the Synthesis of Propylene Carbonates from Carbon Dioxide and Epoxides

Molecules ◽

10.3390/molecules23092304 ◽

2018 ◽

Vol 23 (9) ◽

pp. 2304 ◽

Cited By ~ 1

Author(s):

Li Xia ◽

Wen-Zhen Wang ◽

Shuang Liu ◽

Xin-Gang Jia ◽

Ying-Hui Zhang ◽

...

Keyword(s):

Carbon Dioxide ◽

Catalytic Activity ◽

Catalytic Reaction ◽

Density Functional ◽

Time Pressure ◽

Catalytic Performance ◽

Tridentate Ligand ◽

X Ray Diffraction ◽

Pyridine Ligand ◽

Reaction Conditions

We aimed to develop new effective catalysts for the synthesis of propylene carbonate from propylene oxide and carbon dioxide. A kind of Mx+LClx coordination complex was fabricated based on the chelating tridentate ligand 2,6-bis[1-(phenylimino)ethyl] pyridine (L). The obtained products were characterized by elemental analysis, infrared spectroscopy, ultraviolet spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction. It was found that the catalytic activity of the complexes with different metal ions, the same ligand differed and co-catalyst, where the order of greatest to least catalytic activity was 2 > 3 > 1. The catalytic system composed of complex 2 and DMAP proved to have the better catalytic performance. The yields for complex 2 systems was 86.7% under the reaction conditions of 100 °C, 2.5 MPa, and 4 h. The TOF was 1026 h−1 under the reaction conditions of 200 °C, 2.5 MPa, and 1 h. We also explored the influence of time, pressure, temperature, and reaction substrate concentration on the catalytic reactions. A hypothetical catalytic reaction mechanism is proposed based on density functional theory (DFT) calculations and the catalytic reaction results.

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Absolute Configuration of Mycosporine-Like Amino Acids, Their Wound Healing Properties and In Vitro Anti-Aging Effects

Marine Drugs ◽

10.3390/md18010035 ◽

2019 ◽

Vol 18 (1) ◽

pp. 35 ◽

Cited By ~ 2

Author(s):

Maria Orfanoudaki ◽

Anja Hartmann ◽

Mostafa Alilou ◽

Thomas Gelbrich ◽

Patricia Planchenault ◽

...

Keyword(s):

Amino Acids ◽

Wound Healing ◽

Absolute Configuration ◽

Water Soluble ◽

X Ray Diffraction ◽

Aging Effects ◽

Wide Range ◽

Glycation End Products ◽

Collagenase Inhibition

Mycosporine-like amino acids (MAAs) are water-soluble metabolites, reported to exhibit strong UV-absorbing properties. They have been found in a wide range of marine organisms, especially those that are exposed to extreme levels of sunlight, to protect them against solar radiation. In the present study, the absolute configuration of 14 mycosporine-like-amino acids was determined by combining the results of electronic circular dichroism (ECD) experiments and that of advanced Marfey’s method using LC-MS. The crystal structure of a shinorine hydrate was determined from single crystal X-ray diffraction data and its absolute configuration was established from anomalous-dispersion effects. Furthermore, the anti-aging and wound-healing properties of these metabolites were evaluated in three different assays namely the inhibition of collagenase, inhibition of advanced glycation end products (AGEs) and wound healing assay (scratch assay).

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On Catalytic Behavior of Bulk Mo2C in the Hydrodenitrogenation of Indole over a Wide Range of Conversion Thereof

Catalysts ◽

10.3390/catal10111355 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1355

Author(s):

Marek Lewandowski ◽

Rafał Janus ◽

Mariusz Wądrzyk ◽

Agnieszka Szymańska-Kolasa ◽

Céline Sayag ◽

...

Keyword(s):

Catalytic Activity ◽

Molybdenum Carbide ◽

Nitrogen Adsorption ◽

Operating Conditions ◽

X Ray Diffraction ◽

Catalytic Behavior ◽

Wide Range ◽

Temperature Programmed ◽

Temperature Programmed Reaction ◽

Resultant Material

The catalytic activity of bulk molybdenum carbide (Mo2C) in the hydrodenitrogenation (HDN) of indole was studied. The catalyst was synthesized using a temperature-programmed reaction of the respective oxide precursor (MoO3) with the carburizing gas mixture of 10 vol.\% CH4/H2. The resultant material was characterized using X-ray diffraction, CO chemisorption, and nitrogen adsorption. The catalytic activity was studied in the HDN of indole over a wide range of conversion thereof and in the presence of a low amount of sulfur (50 ppm), which was used to simulate the processing of real petroleum intermediates. The molybdenum carbide has shown high activity under the tested operating conditions. Apparently, the bulk molybdenum carbide turned out to be selective towards the formation of aromatic products such as ethylbenzene, toluene, and benzene. The main products of HDN were ethylbenzene and ethylcyclohexane. After 99% conversion of indole HDN was reached (i.e., lack of N-containing compounds in the products was observed), the hydrogenation of ethylbenzene to ethylcyclohexane took place. Thus, the catalytic behavior of bulk molybdenum carbide for the HDN of indole is completely different compared to previously studied sulfide-based systems.

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