502-41-0Relevant academic research and scientific papers
Kinetics of Peroxyradical Attack at Cyclic Hydrocarbons: Ring-Strain Effects on H-Abstraction
Harnisch, Ralf,Lauterbach, Gerlinde,Pritzkow, Wilhelm
, p. 60 - 62 (1995)
Relative autoxidation rates were determined for the cycloalkanes C7 to C12, the methyl cycloalkanes C6 to C9 and the ethyl cycloalkanes C5 to C9 (ring size in each case) by competitive oxidation of the cycloparaffins with cumene.In the case of the methyl and ethyl cycloalkanes the reactivities of the tertiary C-H bonds coould be calculated from the amounts of tertiary alcohols formed after LiAlH4 reduction of the oxidates.As expected, the C-H reactivities are especially low in six-membered cycloparaffins and especially high in five-, seven- and eight-membered cycloparaffins.The C-H reactivity of cyclododecane lies in the same order of magnitude as the reactivities of secondary C-H bonds of normal paraffins.
Meerwein-Ponndorf-Verley reduction of cycloalkanones over magnesium-aluminium oxide
Aramendía, María A.,Borau, Victoriano,Jiménez, César,Marinas, José M.,Ruiz, José R.,Urbano, Francisco J.
, p. 1122 - 1125 (2002)
MgO-Al2O3 obtained from layered double hydroxide has been studied as a catalyst in the Meerwein-Ponndorf-Verley (MPV) reduction of cycloalkanones and substituted cyclohexanones in the liquid phase. Conversions for cycloalkanones always exceeded 95% and the selectivity was 100% within thefirst 10h of reaction. In the MPV reduction of 4-tert-butylcyclohexanone to 4-tert-butylcyclohexanol a high stereoselectivity (cis:trans ratio > 12) was obtained. This stereoselectivity is explained by the transition-state selectivity imposed by the adsorption complex. For the reduction of cyclohexanone, a recycling test showed that the catalyst can be reused up to four times without losing more than 10% catalytic activity.
Synthesis of luminescent rhodium(III) cyclometalated complex by sp2(C)–S bond activation: Application as catalyst in transfer hydrogenation of ketones and live cell imaging
Roy, Puspendu,Sarkar, Deblina,Ghosh, Paramita,Manna, Chandan Kumar,Murmu, Nabendu,Mondal, Tapan Kumar
, (2020)
A new fluorescent Rh(III) cyclometalated complex, [Rh(PPh3)2(L)Cl] (1) is synthesized via sp2(C)–S bond activation of a thioether containing azo-phenol ligand (L-SCH2CH3). The pseudo octahedral geometry around rhodium is confirmed by single crystal X-ray diffraction method. Cyclic voltammogram of the complex exhibits a quasi-reversible oxidation couple with E1/2 of 0.74 V (ΔE = 100 mV) along with a quasi-reversible reduction couple (E1/2 = ?1.18 V, ΔE = 130 mV) in acetonitrile. The complex exhibits low energy emission band at 682 nm with emission quantum yield (? = 0.103) upon excitation at 583 nm. Cytotoxicity of the complex is studied by MTT method with human breast cancer cell lines and IC50 value is found to 18.5 μM. In presence of the complex (10 μM) a bright red fluorescence image of MCF-7 cell lines is observed under fluorescence microscope. Moreover, the complex acts as effective catalyst towards transfer hydrogenation of ketones.
Extending the family of quinolone antibacterials to new copper derivatives: self-assembly, structural and topological features, catalytic and biological activity
Xerras, Panagiotis,Bacharidou, Anna-Maria,Kalogiannis, Stavros,Perdih, Franc,Kirillova, Marina V.,Kirillov, Alexander M.,Turel, Iztok,Psomas, George
, p. 19644 - 19658 (2018)
A new series of copper(ii) compounds, [Cu(pef)2(MeOH)] (1), [Cu(pef)(bipyam)Cl] (2), [Cu(pef)(phen)Cl] (3) and [Cu(pef)(bipy)Cl] (4), bearing the quinolone family member pefloxacin (Hpef) were self-assembled in the presence (optional) of N,N′-donor heterocyclic ligands such as 2,2′-bipyridylamine (bipyam), 1,10-phenanthroline (phen), or 2,2′-bipyridine (bipy). The products were fully characterized, including single-crystal X-ray diffraction analysis of 2-4. The structures are extended into 1D (2), 2D (3), or 3D (4) networks via multiple H-bonds between the monocopper(ii) units and guest water and/or methanol molecules; the latter are arranged into different types of water and hybrid water-methanol clusters. The resulting H-bonded networks were classified from a topological viewpoint, revealing diverse topologies that also include an undocumented type. Compounds 2-4 also act as homogeneous catalysts in a model oxidation reaction, namely the mild oxidation of C6-C8 cycloalkanes by H2O2 at 50 °C to give cyclic alcohols and ketones. The effects of various reaction parameters (substrate scope, temperature, and loadings of catalyst, cycloalkane, and oxidant) and selectivity features were investigated. Besides, products 1-4 also show remarkable antibacterial activity against four different microorganisms (Escherichia coli, Xanthomonas campestris, Staphylococcus aureus and Bacillus subtilis), which is superior to that of free Hpef. The interaction of the Cu(ii) compounds with calf-thymus DNA was studied suggesting intercalation as the most possible binding mode. Furthermore, the interaction of the obtained copper(ii) derivatives with human/bovine serum albumin was investigated by fluorescence emission spectroscopy and the corresponding albumin-binding constants were established. This study widens a limited family of transition metal pefloxacin derivatives.
Oxidoreduction between Cycloalkanols and Cycloalkanones in the Cultured Cells of Nicotiana tabacum. Correlation of the Reaction Rate with the 13C NMR Chemical Shift of the Carbonyl Carbon
Suga, Takayuki,Izumi, Shunsuke,Hirata, Toshifumi
, p. 2053 - 2056 (1986)
The enzyme system responsible for the oxidoreduction between cycloalkanols and their corresponding cycloalkanones in the cultured cells of Nicotiana tabacum was found to be alcohol dehydrogenase which is similar to the dehydrogenase from tea seeds and horse liver.The rate constants and the equilibrium constants of the oxidoreduction between the cycloalkanols and their corresponding cycloalkanones with this enzyme system were well correlated with the 13C NMR chemical shift of the carbonyl carbon of the oxidation products, i.e., the cycloalkanones.
Aluminum metal-organic framework as a new host for preparation of encapsulated metal complex catalysts
Chen, Yanfeng,Fan, Binbin,Lu, Ningyue,Li, Ruifeng
, p. 91 - 95 (2015)
A facile strategy for encapsulation of metal complex guests into MOFs was proposed. This strategy involves pre-adsorbing metal salt on MOF, and then coordinating the metal ions with the organic ligand, as exemplified by encapsulation of tris(1,10-phenanthroline) Cu(II) complexes (CuPhen) in MIL-100(Al) (denoted as CuPhen/MIL). CuPhen encapsulated in MIL-100(Al) showed higher catalytic activity than the neat CuPhen and CuPhen encapsulated in zeolite-Y. The prepared CuPhen/MIL catalyst was stable and could be reused at least three times without significant loss in activity. This work is beneficial for the host-guest chemistry study and the development of new heterogeneous catalysts.
Mild oxidative C?H functionalization of alkanes and alcohols using a magnetic core-shell Fe3O4@mSiO2@Cu4 nanocatalyst
Kirillova, Marina V.,Santos, Carla I.M.,Wu, Wenyu,Tang, Yu,Kirillov, Alexander M.
, p. 343 - 349 (2017)
A new hybrid Fe3O4@mSiO2@Cu4 material was constructed by loading a bio-inspired tetracopper(II) coordination compound [Cu4(μ4-O){N(CH2CH2O)3}4(BOH)4][BF4]2 (Cu4) onto the Fe3O4@mSiO2 core-shell nanoparticles (NPs) composed of a magnetite (Fe3O4) core and mesoporous silica (mSiO2) shell with perpendicularly aligned channels. The obtained Fe3O4@mSiO2@Cu4 magnetic nanoparticles were characterized by transmission electron microscopy (TEM), FT-IR spectroscopy, thermogravimetric analysis (TGA), powder X-ray diffraction (PXRD), and field-dependent magnetization. This hybrid material acts as a magnetically recoverable C?H functionalization nanocatalyst, namely for the mild oxidation, by t-butyl hydroperoxide at 50–70?°C in acetonitrile medium, of cycloalkanes (cyclopentane, cyclohexane, cycloheptane, and cyclooctane) to the corresponding alcohols and ketones (with up to ～15% yields based on cycloalkane; TON 335). A related oxidation process using cyclohexanol as a more reactive substrate leads to the formation of cyclohexanone in up to ～25% yield (TON 570). The Fe3O4@mSiO2@Cu4 nanocatalyst can be recycled five times without an appreciable loss of activity. The bond-, regio-, and stereoselectivity parameters were investigated in the oxidation of different alkane substrates (n-hexane, n-heptane, n-octane, methylcyclohexane, adamantane, cis- and trans-1,2-demethylcyclohexane), and the obtained results were compared with the homogeneous systems based on the Cu4 catalyst. In particular, the high bond selectivity parameters detected in the oxidation of methylcyclohexane (1°:2°:3° of 1:8:142) and adamantane (2°:3° of 1:21) catalyzed by Fe3O4@mSiO2@Cu4 suggest that the reactions possibly occur in hydrophobic pockets of the nanocatalyst.
Cu6- And Cu8-Cage Sil- And Germsesquioxanes: Synthetic and Structural Features, Oxidative Rearrangements, and Catalytic Activity
Astakhov, Grigorii S.,Levitsky, Mikhail M.,Zubavichus, Yan V.,Khrustalev, Victor N.,Titov, Aleksei A.,Dorovatovskii, Pavel V.,Smol'Yakov, Alexander F.,Shubina, Elena S.,Kirillova, Marina V.,Kirillov, Alexander M.,Bilyachenko, Alexey N.
, p. 8062 - 8074 (2021/05/26)
This study reports intriguing features in the self-assembly of cage copper(II) silsesquioxanes in the presence of air. Despite the wide variation of solvates used, a series of prismatic hexanuclear Cu6 cages (1-5) were assembled under mild conditions. In turn, syntheses at higher temperatures are accompanied by side reactions, leading to the oxidation of solvates (methanol, 1-butanol, and tetrahydrofuran). The oxidized solvent derivatives then specifically participate in the formation of copper silsesquioxane cages, allowing the isolation of several unusual Cu8-based (6 and 7) and Cu6-based (8) complexes. When 1,4-dioxane was applied as a reaction medium, deep rearrangements occurred (with a total elimination of silsesquioxane ligands), causing the formation of mononuclear copper(II) compounds bearing oxidized dioxane fragments (9 and 11) or a formate-driven 1D coordination polymer (10). Finally, a "directed"self-assembly of sil- and germsesquioxanes from copper acetate (or formate) resulted in the corresponding acetate (or formate) containing Cu6 cages (12 and 13) that were isolated in high yields. The structures of all of the products 1-13 were established by single-crystal X-ray diffraction, mainly based on the use of synchrotron radiation. Moreover, the catalytic activity of compounds 12 and 13 was evaluated toward the mild homogeneous oxidation of C5-C8 cycloalkanes with hydrogen peroxide to form a mixture of the corresponding cyclic alcohols and ketones.
A Zr-Based Metal-Organic Framework with a DUT-52 Structure Containing a Trifluoroacetamido-Functionalized Linker for Aqueous Phase Fluorescence Sensing of the Cyanide Ion and Aerobic Oxidation of Cyclohexane
Gogoi, Chiranjib,Nagarjun, Nagarathinam,Roy, Shubasis,Mostakim,Volkmer, Dirk,Dhakshinamoorthy, Amarajothi,Biswas, Shyam
supporting information, p. 4539 - 4550 (2021/04/06)
A zirconium (Zr) metal-organic framework having a DUT-52 (DUT stands for Dresden University of Technology) structure with face-centered cubic topology and bearing the rigid 1-(2,2,2-trifluoroacetamido) naphthalene-3,7-dicarboxylic acid (H2NDC-NHCOCF3) ligand was prepared, and its solid structure was characterized with the help of the X-ray powder diffraction (XRPD) technique. Other characterization methods like thermogravimetric analysis (TGA) and Fourier transform infrared (FT-IR) spectroscopy were applied to verify the phase purity of the compound. In order to get the solvent-free compound (1′), 1 was stirred with methanol for overnight and subsequently heated at 100 °C overnight under vacuum. As-synthesized (1) and activated (1′) compounds are thermally stable up to 300 °C. The Brunsuer Emmett-Teller (BET) surface area of 1′ was found to be 1105 m2 g-1. Fluorescence titration experiments showed that 1′ exhibits highly selective and sensitive fluorescence turn-on behavior toward cyanide (CN-) anion. The interference experiments suggested that other anions did not interfere in the detection of CN-. Moreover, a very short response time (2 min) was shown by probe 1′ for CN- detection. The detection limit was found to be 0.23 μM. 1′ can also be effectively used for CN- detection in real water samples. The mechanism for the selective detection of CN- was investigated systematically. Furthermore, the aerobic oxidation of cyclohexane was performed with 1′ under mild reaction conditions, observing higher activity than the analogous DUT-52 solid under identical conditions. These experiments clearly indicate the benefits of hydrophobic cavities of 1′ in achieving higher conversion of cyclohexane and cyclohexanol/cyclohexanone selectivity. Catalyst stability was proved by two consecutive reuses and comparing the structural integrity of 1′ before and after reuses by the XRPD study.
Time-Dependent Self-Assembly of Copper(II) Coordination Polymers and Tetranuclear Rings: Catalysts for Oxidative Functionalization of Saturated Hydrocarbons
Costa, Ines F. M.,Kirillova, Marina V.,André, Vania,Fernandes, Tiago A.,Kirillov, Alexander M.
supporting information, p. 14491 - 14503 (2021/07/19)
This study describes a time-dependent self-assembly generation of new copper(II) coordination compounds from an aqueous-medium reaction mixture composed of copper(II) nitrate, H3bes biobuffer (N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid), ammonium hydroxide, and benzenecarboxylic acid, namely, 4-methoxybenzoic (Hfmba) or 4-chlorobenzoic (Hfcba) acid. Two products were isolated from each reaction, namely, 1D coordination polymers [Cu3(μ3-OH)2(μ-fmba)2(fmba)2(H2O)2]n (1) or [Cu2(μ-OH)2(μ-fcba)2]n (2) and discrete tetracopper(II) rings [Cu4(μ-Hbes)3(μ-H2bes)(μ-fmba)]·2H2O (3) or [Cu4(μ-Hbes)3(μ-H2bes)(μ-fcba)]·4H2O (4), respectively. These four compounds were obtained as microcrystalline air-stable solids and characterized by standard methods, including the single-crystal X-ray diffraction. The structures of 1 and 2 feature distinct types of metal-organic chains driven by the μ3- or μ-OH- ligands along with the μ-benzenecarboxylate linkers. The structures of 3 and 4 disclose the chairlike Cu4 rings assembled from four μ-bridging and chelating aminoalcoholate ligands along with μ-benzenecarboxylate moieties playing a core-stabilizing role. Catalytic activity of 1-4 was investigated in two model reactions, namely, (a) the mild oxidation of saturated hydrocarbons with hydrogen peroxide to form alcohols and ketones and (b) the mild carboxylation of alkanes with carbon monoxide, water, and peroxodisulfate to generate carboxylic acids. Cyclohexane and propane were used as model cyclic and gaseous alkanes, while the substrate scope also included cyclopentane, cycloheptane, and cyclooctane. Different reaction parameters were investigated, including an effect of the acid cocatalyst and various selectivity parameters. The obtained total product yields (up to 34% based on C3H8 or up to 47% based on C6H12) in the carboxylation of propane and cyclohexane are remarkable taking into account an inertness of these saturated hydrocarbons and low reaction temperatures (50-60 °C). Apart from notable catalytic activity, this study showcases a novel time-dependent synthetic strategy for the self-assembly of two different Cu(II) compounds from the same reaction mixture.
