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The forward osmosis (FO) membrane exhibits great performance degradation when contacting with chlorine solutions. The damage of chlorine to membrane material will seriously reduce the lifetime of the membrane and increase the cost of membrane treatment technology. Here, we prepared chlorine-stable membranes by a covalent modification method with cyclohexylamine. The cyclohexylamine observably changed the surface morphology, the roughness (arithmetic average) of the membrane decreased from 22 to 17.2 nm. The addition of cyclohexylamine produced a denser sacrificial layer of short chain polyamide, which made modified membranes possess significantly better chlorine resistance with slightly declined water flux. The water flux of the optimal modified membrane was 10.78 Lm−2 h−1, only 13% less than that of the pristine membrane. Importantly, after 20,000 ppm·h chlorine exposure, the membrane with 1.5 wt% cyclohexylamine had a salt rejection of 77.2% and showed 26.0% lower water flux than pristine TFC (thin film composite) membrane in FO mode. Notably, the grafting membranes could maintain a high performance under acidic chlorination conditions. The membrane with best performance had a salt rejection of 81.6%, exhibiting 24.4% higher salt rejection than pristine membrane with 20,000 ppm·h chlorine exposure at a pH of 4. The cyclohexylamine endowed the FO membrane with better chlorine resistance, making it attractive for the development of chlorine-resistant membrane for environmental and desalination processes. HIGHLIGHTS The addition of cyclohexylamine produced a chlorine-resistant sacrificial layer.; The 1.0 wt% addition of cyclohexylamine did not significantly decrease the water flux of the forward osmosis membrane.; Under acidic conditions, cyclohexylamine could still significantly improve the chlorine resistance of forward osmosis membranes.

1,3-Dichloro-1,3-bis(dimethylamino)propenium salts react with primary amines to give different products depending on the structure of the amine. Reactions in which the primary amine is bonded to a tertiary carbon (tert-butylamine and 1-adamantylamine) result in 1,1-bis(dimethylamino)-3,3-bis(alkylamino)propenium salts which form via a 1,3-dimethylamino shift. In contrast, the reactions in which the primary amine is bonded to a secondary carbon (cyclohexylamine, cyclopentylamine, and sec-butylamine) result in 1-(ylidene)amino-1,3-bis(dimethylamino)propenium salts which form via an intramolecular hydride shift. All of the synthesized compounds have been fully characterized using spectroscopic methods, including single crystal X-ray diffraction. Finally, the mechanisms of the intramolecular rearrangements have been investigated computationally at the ωB97X-D/6-311G(d,p) level of theory, suggesting that the reactions proceed through putative keteniminium species.

Two bidentate PNP ligands N,N-bis(di-p-tolylphosphino)cyclohexylamine (Cy-pTolPNP) (1) and N,N-bis(di-p-tolylphosphino)cyclobutylamine (Cb-pTolPNP) (2) were synthesized and crystallized. Coordination to the fac-[MI(CO)3]+ core (M = Re, 99Tc) yielded fac-[Re(Cy-pTolPNP)(CO)3Br] (1A), fac-[99Tc(Cy-pTolPNP)(CO)3Cl] (1B), fac-[Re(Cb-pTolPNP)(CO)3Br] (2A) and fac-[99Tc(Cb-pTolPNP)(CO)3Cl] (2B) in relatively good yields (56 to 86 %): The structures of 1, 2, 1A and 1B were studied by single crystal X-ray crystallography. Preliminary mitochondrial/antimicrobial evaluation of the free ligand (N,N-bis(di-p-tolylphosphino)-cyclohexylamine) (1) and its respective fac-[Re(CO)3]+ (1A) complex indicates that neither the free ligand nor the complex was active against selected fungi Eremothecium ashbyii and Nadsonia fulvescens. In addition, all four compounds were found to have no activity against Gram-positive and Gram-negative bacterial species. These biological results are essential to the understanding of how these types of complexes behave and show they are perfectly stable in the evaluated bio-environments. In addition, the results indicate that these ligands and complexes may present themselves as excellent models for radiotoxicity studies using technetium-99m, but more specifically, rhenium Re-186 and Re-188.

Cyclohexylamine (CHA) is used as an important raw material in chemical industries. Since the production of CHA requires a high temperature and excess amounts of hydrogen gas (H2) and ammonia, the development of a simple reaction operated under milder conditions using a safe compound is indispensable for achieving sustainable chemistry. A highly selective ring hydrogenation of aniline (AN) to CHA over a titanium(IV) oxide photocatalyst having a co-catalyst in water at room temperature, in which oxalic acid was used as the hydrogen source in place of H2, is described in this paper. Among TiO2 photocatalysts having co-catalysts, Rh-TiO2 showed high activity for CHA production, while Pd-TiO2 and Ru-TiO2 showed negligible activity. When a bimetallic photocatalyst, Ru/Pd-TiO2, was used, the yield was larger than that when Rh-TiO2 was used. Metal particles loaded on TiO2 were observed by using TEM, and electronic states of Ru and Pd were evaluated by using XPS. Interactions among metal, AN and CHA were investigated through adsorption experiments. Based on the results, active sites for AN hydrogenation are discussed.

The data on adsorbability of oleamides and hexylamine, cyclohexylamine, morpholine, piperidine, and piperazine salts of oleic acid are systematized in this study. The protective mechanism of these compounds is studied in order to reveal a correlation between the inhibiting ability and the calculated parameters of the molecules. A procedure for measuring the Volta potential difference using a Poverkhnost-II high-sensitivity digital electrometer under the conditions when water- and hydrocarbon-soluble corrosion inhibitors interact with the steel and copper surface is elaborated. It has been proven that a high-efficiency corrosion inhibitor can be designed based on the data on its donor properties and adsorbability.

Nitrogen-doped bamboo-like carbon nanotube (N-BCNT) coating was synthesized onto the surface of zeolite beads by using Catalytic Chemical Vapour Deposition (CCVD) method to develop a “support on support” (SoS) system. These complex structured materials were used as supports during the preparation of hydrogenation catalysts. Rhodium, palladium and platinum nanoparticles were deposited homogeneously onto the surface of the N-BCNTs of the SoS (final metal content 2 wt%). The catalytic activity of these samples was compared in the hydrogenation of nitrobenzene. The Pt/N-BCNT-zeolite sample was the most active (182 mol nitrobenzene after 30 min). The activity of the other two catalysts at 20 bar was well below this value, 99.5 mol after 60 min and 96 mol after 120 min for Pd and Rh, respectively. The aniline selectivity was different for the three catalysts and they facilitate the formation of various by-products (e.g. N-methylaniline, cyclohexylamine). The usage of the Pd and Pt/N-BCNT-zeolite catalysts are more convenient, as only one main by-product was formed. It was confirmed that the zeolite supported N-BCNTs are efficient catalyst supports in hydrogenation processes. Furthermore, by using this special SoS structure to support the catalytic metals the applicability is widened and the catalyst removal is easier.

The present work is aiming to utilize Re based catalysts for hydrodenitrogenation (HDN) of cyclohexylamine over SBA-15 supported catalyst under optimized conditions. Siliceous SBA-15 was synthesized by hydrothermal method and used as a support for Re catalysts with different Re loadings (1, 3, 5 and 7 wt%). The supported catalysts were characterized by various physico-chemical techniques like XRD, N2-sorption studies, UV-DRS, FE-SEM, HR-TEM, NH3-TPD, Raman spectroscopy and XPS (sulfided catalyst). The oxide catalysts were presulfided before the hydrodenitrogenation reaction using ditertiary butyl polysulfide (DBPS) as sulfiding agent and hydrogen. The catalytic activity of the sulfided catalysts was tested for HDN of cyclohexylamine. A high HDN activity was observed on 5 wt% Re loaded SBA-15 catalyst. The catalytic activity was correlated with characterization results.

The influence of domestic nitrogen-containing corrosion inhibitors of the VNKh-L type on corrosion regularities of a zinc coating on steel in neutral media is investigated. This work is aimed at studying the surface structure of a corroding zinc coating, as well as the influence of conditions simulating the degradation of inhibitors during real operation on their protective properties. Mechanical activation in a ball planetary mill is used to simulate the deformation and thermal operational conditions of inhibitors. Corrosion of a zinc coating on steel is carried out in a sulfate–chloride medium simulating atmospheric corrosion and in a borate buffer solution. The concentration of inhibitors in the corrosion media was 0.2 wt %. The morphology of a corroded surface of a zinc coating is studied using a Philips SEM-515 scanning electron microscope (at an accelerating voltage of 10 kV) with an X-ray microprobe. Studies of the corrosion rate of zinc coating on St 08 are carried out by the indirect measurement of corrosion resistance with the help of a MONIKOR-1 corrosion meter. A borate buffer solution (Na2B4O7 + H3BO3, pH 6.6) and a solution simulating atmospheric corrosion (NaCl + Na2SO4, pH 6.0) are used as corrosion media. The corrosion rate of samples in corrosive media without an inhibitor is accepted 1. The exposure time of each sample in corrosive media is 3 h. The chemical composition of corrosion products is studied by the mirror reflection in the IR range. The IR spectra of the metal plate surface are recorded using an FSM-1202 IR Fourier spectrometer in a wavelength range of 450–4000 cm–1 with a resolution of 2 cm–1 and an accumulation of 100 scans. To record the reflection spectra, a mirror-reflection attachment with a 10° angle of incidence is used. The corrosion rate of zinc coating in sulfate–chloride and solvent media in the presence of inhibitors based on benzotriazole and cyclohexylamine is practically not decreased when compared with the corrosion rate in the same media without inhibitors. The addition of both initial and mechanically activated inhibitors based on morpholine and benzotriazole to the corrosion medium decreases the corrosion rate of iron when compared with the corrosion in the same media without inhibitors. The pitting corrosion of a zinc coating is observed in the presence of initial and mechanically activated inhibitors of both types in studied corrosion media. Herewith, the pitting depth is smaller than the zinc-coating thickness under these conditions.

A new sample preparation method, cyclohexylamine-based heat-induced homogeneous liquid–liquid microextraction, has been developed for the extraction and preconcentration of Cd(II) and Zn(II) ions in edible oils followed by flame atomic absorption spectrometry determination. First, the analytes are extracted into an acidic solution (a balanced mixture of HNO3 and HCl). Second, they are preconcentrated via the microextraction method. Accordingly, cyclohexylamine (as a complexing agent and an extraction solvent) is added at µL-level into the obtained solution containing the analytes to form a homogeneous solution followed by the addition of sodium chloride. After manual shaking, the obtained solution is placed in a water bath thermostated at 60 °C. A cloudy solution because of the decrease in cyclohexylamine solubility in water at high temperature is formed. After centrifuging fine droplets of cyclohexylamine containing Cd(II) and Zn(II)—cyclohexylamine complexes are collected on the top of the aqueous phase. The preconcentrated analytes in the upper phase by use of flame atomic absorption spectrometry are analyzed and determined. Several variables possibly affecting the extraction efficiency were investigated and optimized. Under the optimum conditions, the calibration curves were linear in the ranges of 10–300 and 2.5–200 µg kg− 1 for Cd(II) and Zn(II), respectively. Repeatability of the proposed method, expressed as relative standard deviation, was obtained 2.4 and 1.7% for Cd (II) and Zn(II), respectively. Moreover, the detection limits of the selected analytes were obtained 3.8 and 0.6 µg kg− 1 for Cd(II) and Zn(II), respectively.

A green and efficient approach for solvent-free selective catalytic oxidation of cyclohexylamine to cyclohexanone oxime in liquid phase has been developed. The results showed that the supported 30%TiO2/MCM-41 as efficient and eco-friendly catalyst gave 78.4% of cyclohexylamine conversion with 89.1% of selectivity to cyclohexanone oxime. It has been demonstrated that the catalytic active sites are the surface titanium hydroxyl groups of catalyst. Moreover, the present catalyst can be easily separated, recycled, regenerated and reused. The probable catalytic reaction mechanism of cyclohexylamine with molecular oxygen over supported TiO2/MCM-41 was suggested. This work affords a new and environmentally friendly route for the synthesis of cyclohexanone oxime, and has important industrial application prospects.

A direct and efficient palladium-catalyzed reductive coupling reaction of nitroarenes with phenols has been developed. A series of N-cyclohexylaniline derivatives was easily and efficiently obtained in moderate to good yields via C–N bond formation by the simple use of safe and inexpensive sodium formate as the hydrogen donor.

The effect of amines, imines and heterocycle compounds on conversion has been studied in transfer hydrogenation of camphor and 2-PrOH catalyzed by Raney® nickel. Small amount (5 mol% to nickel) of N-containing compound significantly decreases catalyst activity. It has been shown that the poisoning effect mostly depends on molecular size of amines and heterocyclic compounds. For aniline and cyclohexylamine the dependence of camphor conversion on poison/nickel ratio was obtained. Additionally, benzaldehyde, cinnamaldehyde demonstrated higher reactivity compared corresponding imines under transfer hydrogenation conditions. Obtained data explain low activity of nickel-based catalysts when N-containing compounds are presented in reaction mixture.

Porous clay heterostructures were prepared from Al-intercalated clays, and they allowed the insertion of Al into the framework of intercalated silica in porous clay heterostructures (PCHs). This method has led to tuneable Al contents within the resulting porous clay heterostructures. X-ray fluorescence confirmed the presence of Al in the intercalated precursors and their derivatives (porous clay heterostructure materials) in various environments, as indicated by 27Al magic-angle spinning nuclear magnetic resonance. The Al porous clay heterostructures exhibited specific surface areas that varied from 743 to 850 m2/g with total acid concentrations which varied from 0.969 to 1.420 mmol of protons/g of material, values which were deduced from the temperature desorption of cyclohexylamine. These acid sites were sufficiently strong to initiate the hydro-isomerization of n-heptane. The catalytic properties of the porous clay heterostructures depended on the Al contents and reached a maximum conversion rate of 50% and an isomer selectivity of 70% at a test reaction temperature of 350°C.

The chemisorption of (acetylacetonato)copper(II) on gold-nanoparticle- (Au-NP-) loaded rutile TiO2 and subsequent heating in the air at 773 K yields molecular-scale CuO clusters on the TiO2 surface with varying CuO loading amounts (Au/TiO2–CuO) (J. Phys. Chem. C 2013, 117, 23848−23857). The three-component Au/TiO2–CuO plasmonic photocatalyst exhibits a high level of visible-light activity for the selective aerobic oxidation of cyclohexylamine to cyclohexanone at room temperature. The photocatalytic activity far exceeds those of the Au/TiO2 and TiO2–CuO two component systems. Photoelectrochemical experiments indicate that the electrons injected from Au NPs into TiO2 by the localized surface plasmon resonance excitation are transferred to the CuO clusters through simultaneous visible-light excitation from the valence band of TiO2 to the surface CuO-derived levels. Consequently, the high activity originates from the electron-collecting and -concentrating effects of the CuO clusters with an electrocatalytic a...

A simple and environmentally benign approach to highly selective preparation of cyclohexanone oxime by vapor phase catalytic oxidation of cyclohexylamine with air over mesoporous silica gel under atmospheric pressure has been successfully developed in this work. The results demonstrate that the nonmetallic mesoporous silica gel is an effective and eco-friendly catalyst for the vapor phase selective oxidation of cyclohexylamine to cyclohexanone oxime and the surface silicon hydroxyl groups as active sites are responsible for the excellent catalytic performance of silica gel. The present silica gel catalyst has advantages of low cost, long-time stable reactivity, easy regeneration, and reusability. This method employing inexpensive mesoporous silica gel as catalyst and air as green terminal oxidant under facile conditions is a promising process and has the potential to enable sustainable production of cyclohexanone oxime from the selective oxidation of cyclohexylamine with air in industrial applications.

The carbon supported 10% Ni catalysts doped with 3‰ Rh have been prepared by an impregnation method. These catalysts have been used to catalyze the one-step hydrogenation of nitrobenzene to cyclohexylamine. The results show that the 3‰ Rh–10% Ni/CSC (biocarbon) catalyst exhibits an excellent performance to achieve 100 mol% conversion of nitrobenzene and 91.6% selectivity of cyclohexylamine under reaction conditions of 3.5 MPa and 140 °C. The recycling tests reveal recyclable stability of 3‰ Rh–10% Ni/CSC. This catalyst is active for the hydrogenation of a series of electron-deficient nitrobenzenes. Some factors such as the type of carriers, the content of Ni and Rh, the type of metals and additives play important roles in controlling the selective hydrogenation.

The reaction of 2-acetylpyridine, cyclohexylamine and copper(II) perchlorate in methanol resulted in the dinuclear copper(II) complex [Cu2L2]·2ClO4, where L is the monoanionic form of 1-methoxy-1,3...

The μ4-oxido motif is well known in copper clusters and often forms spontaneously and unexpectedly; however, little is known about the reaction conditions that generate μ4-oxido clusters. This is surprising because these μ4-oxido copper clusters seem to play an important role in catalysis. Herein, a systematic investigation of μ4-oxido cluster formation is reported. The influence of several factors on cluster formation was studied, namely, the ligand environment, the central chalcogenide atom, and the bridging halido ligands. In this context, the crystal structures of the copper clusters and complexes [Cu4OCl6L24][CuL22Cl2] (L2 = phenethylamine), [CuL32Cl2] (L3 = N-methylbenzylamine), [Cu4OCl6L44] (L4 = N,N-dimethylbenzylamine), [CuL54Cl2] (L5 = cyclohexylamine), and [Cu4OCl6L64]·1.5[CuL62Cl2] (L6 = cyclohexanemethylamine) as well as that of HL4Cl are reported. Furthermore, the acetonitrile complexes [Cu(CH3CN)4][CuBr4], [Cu(CH3CN)Br], and [Cu(CH3CN)Br2] were obtained and characterized within attempts to prepare a μ4-sulfido unit. The reaction conditions that generate μ4-oxido cluster units are discussed in more detail.

Nano-SiO 2 was immobilized on the inner wall of a dielectric barrier discharge (DBD) tube, and it was coupled to a conventional gas chromatographer to investigate its performance as a molecular emission spectrometric detector for the determination of five volatile aliphatic amines. A charge-coupled device (CCD) was applied to observe the nano-SiO 2 -enhanced molecular emission spectra. The characteristic molecular emission bands of volatile aliphatic amines at 326.5 nm, 336.0 nm and 388.3 nm can be clearly resolved from the background emission spectra of carrier gas argon. The emission band of CN at 388.3 nm was used for quantitative detection of volatile aliphatic amines due to its high sensitivity. Nanomaterial catalysts including TiO 2 , MnO 2 , SiO 2 and ZnO were tested to enhance the emission signal of amines, and SiO 2 shows the best performance. The factors that influence the emission signal, such as discharge voltage, inner electrode length and carrier gas flow rate, were investigated in detail. The analytical performance of this method was evaluated by separation and detection of the mixture of five volatile aliphatic amines. Under the optimal experimental conditions, the limits of detection were found to be 4.4, 2.5, 2.2, 1.8 and 2.4 μg for dimethylamine, trimethylamine, n-butylamine, cyclohexylamine and ethylenediamine, respectively. This GC detector is not only sensitive but also fast in response to volatile aliphatic amines with good stability. Trimethylamine in a carp fish sample was monitored with storage time by the proposed method.

A series of ruthenium nanoparticles (Ru NPs) bearing different ligands on their surfaces have been used as catalysts in the selective hydrogenation of nitrobenzene to cyclohexylamine. Ru C60, Ru-PVP, Ru-HDA, and Ru-IPr [PVP = poly(vinylpyrrolidone); HDA = hexadecylamine, IPr = 1,3-bis(2,6- diisopropylphenyl)imidazol-2-ylidene] have been chosen because of their different electronic properties, with HDA and IPr acting as donor ligands, PVP as a polymer with small interaction with the Ru NP surface, and fullerene C60 as an electron-attractor ligand, while their size and structure remain similar. A clear influence of the ligand on the Ru NP surface on the catalytic performances was observed. The less donor ligands promote hydrogenation of the N-phenylhydroxylamine (PHA) intermediate, which is considered to be the rate-determining step, leading to the more active catalysts, affecting also the chemoselectivity of the reaction. Density functional theory (DFT) calculations show that the hydride coverage of the Ru NPs plays a key role in the adsorption of PHA on the surface of the NPs. This adsorption is indeed unfavored for realistic coverage values, higher than 1.5H/per surface Ru atom, explaining the accumulation of this intermediate under hydrogenation conditions, as observed with all Ru NPs here studied. In addition, DFT calculations show that the adsorption of PHA is favored when fullerene C60 is present on the Ru NP surface compared to the uncapped Ru NPs, which correlates well with the higher turnover frequency observed for Ru-C60 catalyst compared to the other Ru NP systems bearing more donating ligands and also the higher selectivity obtained with this catalyst., This work was supported by the CNRS, which we gratefully acknowledge. We are thankful for financial support (FEDER contribution) from the MINECO (Projects CTQ2016-76267-P and CTQ2016-81797-REDC). I.C.G. acknowledges the Calcul en Midi-Pyrénées initiative CALMIP (Project p0812) for allocation of computer time. This work was also granted access to the HPC resources of CINES and IDRIS under the Allocation 2017-A0040906649 made by GENCI.

Substitution of the aqua ligand from three platinum(II) complexes, namely [Pt(H2O)(N,N-bis(2-pyridylmethyl)cyclohexylamine](ClO4)2 (Pt1); [{Pt(H2O)}2(N,N,N′,N′-tetrakis(2-pyridylmethyl)-trans-1,4-cyclohexyldiamine)](ClO4)4 (Pt2); and [{Pt(H2O)}2(N,N,N′,N′-tetrakis(2-pyridylmethyl)-4,4′-ethylenedicyclohexyldiamine)](ClO4)4 (Pt3), by three biologically relevant nucleophiles [viz., glutathione (Glu); DL-penicillamine (Pen); and l-histidine (His)] was studied in aqueous 0.1 M perchloric acid medium. The substitutions were investigated under pseudo-first-order conditions as a function of nucleophile concentration and temperature using UV–visible spectrophotometry. The reactions of these complexes with the nucleophiles proceeded via a single step whose reactivity decreased in the order: Pt1 > Pt3 > Pt2 and was controlled by steric and electronic influences of the complexes. Sulfur donor nucleophiles (Glu and Pen) reacted much faster than the nitrogen bearing His, with Glu appearing to be more nucleophilic than Pen. The large and negative activation entropies and low but positive enthalpies of activation affirm an associative mode of activation.

Non-metallic mesoporous SBA-15 is firstly used for the gas-phase selective oxidation of cyclohexylamine to cyclohexanone oxime with air and exhibits the best performance among the investigated silica catalysts. The experimental results show that the catalytic activity is strongly dependent on the pore diameter of SBA-15. By combining catalytic performance experiments with the monitoring of catalyst transformations using themogravimetric analyses, N-2-physisorption, and solid-state Si-29 MAS NMR spectra, we show that the surface silanols play important roles to form a catalytically active carbon species, which is believed to be favorable to the activation of molecular oxygen. The carbon species formed are also studied by IR-spectroscopy, coke analysis by a catalyst dissolution/extraction protocol and elemental analyses. (C) 2014 Elsevier B.V. All rights reserved.

Lung cancer is the leading cause of cancer-related death in the United States, and non-small cell lung cancer (NSCLC) the most common type. Platinum (Pt) anticancer agents, such as cisplatin, remain a mainstay in the clinic; however, these agents are not tumor-specific and, thus, the patient experiences negative side-effects. We here prepare trans, cis, cis-bis(heptanoato)amine(cyclohexylamine)dichloridoplatinum(IV) and demonstrate that it is greater than 50-fold more toxic toward NSCLC cells than is cisplatin. Furthermore, it has a much improved therapeutic index. This Pt(IV) complex binds to DNA in a manner similar to that of cisplatin, and can be incorporated into mesoporous silica nanoparticles for fine-controlled release and the targeting of tumors.

The influence of the nature of a cocatalyst, a stabilizing ligand, and an introduced modifier on the behavior of the ethylene oligo- and polymerization reaction in the presence of the Cr(acac)3-AlR3-L-M catalyst system, where AlR3 is triethylaluminum (AlEt3), dichloroethylaluminum (AlEtCl2), or methylalumoxane (MAO); L is pyrrole (PyH) or bis(diphenylphosphino)cyclohexylamine ((Ph2P)2NCy); and M is tetrachloromethane (CCl4), has been studied. The maximal selectivity for hexene-1 has been found to be 86 wt %.

Two novel platinum(II) complexes cis-[Pt(L′)(NH3)X] (where L′ = cyclopentylamine or cyclohexylamine, X = 3-(nitrooxy)cyclobutane-1,1-dicarboxylate) were synthesized and spectrally characterized in this study. The purity of complexes 1 and 2 were studied by HPLC–MS spectra, and the contents of complexes 1 and 2 were more than 98%. It was demonstrated that the newly synthesized compounds with dicarboxylate containing organic nitrate as ligand possessed DNA unwinding capability similar to cisplatin by the means of agarose gel electrophoresis. In addition, the antiproliferative study by WST-8 assay revealed that these platinum(II) complexes exhibited considerable cytotoxicity against tested cancer cell lines in vitro compared with positive agents (cisplatin, oxaliplatin and carboplatin), especially complex 1, showing higher in vitro antitumoractivity than oxaliplatin and carboplatin in SGC7901 and A549 cell lines.

Two novel pendant-armed dialdehydes (1a and 1b) were prepared by a one-step reaction between 5-chloro-3-(chloromethyl)-2-hydroxybenzaldehyde/5-methyl-3-(chloromethyl)-2-hydroxybenzaldehyde and cyclohexylamine involving two nucleophilic substitutions, and they were used to react with 1,3-propanediamine to prepare Schiff-base macrocyclic complexes in the presence of ZnX2 salts (X = Cl, Br, and I). As a result, five dinuclear (2a, 2b, 3b, 4a, and 4b) and one mononuclear (3a) [1 + 1] flexible macrocyclic Zn(II) complexes have been structurally and spectrally characterized. The zinc centers in three pairs of macrocyclic complexes have the common four-coordinate tetrahedral geometry with one or two coordinated halide ions, where the template Zn(II) cations and the auxiliary halide anions with different sizes and coordination abilities are believed to play important roles in forming the resulting macrocyclic complexes. In addition, subtle alterations of electron-withdrawing and electron-donating substituted groups (Cl versus CH3) in the macrocyclic backbone result in different (1)H NMR and UV-vis spectra.

The reaction of Pd(CH3CN)2Cl2 and NaClO4 with the ancillary ligands N,N-di(2-picolyl)cyclopentylamine (L1), N,N-di(2-picolyl)cyclohexylamine (L2) and N,N-di(2-picolyl)cycloheptylamine (L3) in ethanol yielded a new series of [(N,N′,N)-PdCl]ClO4 complexes, i.e., [PdL1]ClO4, [PdL2]ClO4 and [PdL3]ClO4, respectively. The reaction of Pt(CH3CN)2Cl2 and NaClO4 with the ancillary ligands L1–L3 gave only the stable [PtL2]ClO4 complex. The Pd and Pt atoms of all of the complexes had an almost square-planar geometry involving three nitrogen atoms and a chloro ligand. Moreover, the unit cell included a ClO 4 - anion as the counterion. The bond lengths between the metal and nitrogen atoms are a little affected by the substituted cycloalkyl group, however those between the metal and the chloro ligand are not affected. The catalytic activity of the Pd(II) and Pt(II) complexes toward the polymerisation of methyl methacrylate in the presence of modified methylaluminoxane resulted in a high molecular weight and a narrow polydispersity index; the highest activity was measured for [PdL3]ClO4 at 60 °C.

Hydrothermal conversion of magadiite, in the presence of cyclohexylamine (CHA), into a commercially important mordenite (MOR zeolite) has been investigated. The effects of various parameters such as the reactant H 2 O/SiO 2 ratio, CHA/SiO 2 ratio, reaction time, the presence of sodium ions and potassium ions are studied. Thermal and acid stability of the as-made MOR zeolite were examined. The pure MOR zeolite with high crystallinity, which is composed of parallelepiped crystals agglomerate, was obtained at 140 °C for 28 h with the molar composition: 0.14M 2 O:SiO 2 : x Al 2 O 3 :54H 2 O:16CHA (M 2 O = K 2 O + Na 2 O, K/K + Na = 0.3, x = 0.028 and 0.04). The structure of the sample was totally destroyed at 1100 °C and the product is exceptionally stable towards strong acid.

cited By 15; International audience; Electron-deficient ruthenium nanoparticles supported on Ru fulleride nanospheres allow the successive and chemoselective hydrogenation of nitrobenzene to aniline and then to cyclohexylamine. The catalysts were prepared in a straightforward manner by decomposition under dihydrogen of [Ru(COD)(COT)] in the presence of C60. The nitrobenzene hydrogenation reaction is solvent sensitive and proceeds more quickly in methanol than in other alcohols. The same behavior, i.e. a two-step successive hydrogenation, has been observed for several substituted nitroarenes. Density functional theory calculations suggest that the observed chemoselectivity is mainly governed by the presence of surface hydrides on the electron-deficient Ru nanoparticles. At the threshold value of 1.5 H per Ru surface atom, the formation of aniline is favored due to the net preference of the NO2 coordination.

Nickel is found to demonstrate high performance in the amination of cyclohexanol into cyclohexylamine in water and two solvents with low boiling points: tetrahydrofuran and cyclohexane. Three catalysts, Raney Ni, Ni/Al2O3 and Ni/C, were investigated and it is found that the base, hydrogen, the solvents and the support will affect the activity of the catalyst. In water, all the three catalysts achieved over 85% conversion and 90% cyclohexylamine selectivity in the presence of base and hydrogen at a high temperature. In tetrahydrofuran and cyclohexane, Ni/Al2O3 exhibits better activity than Ni/C under optimal conditions. Ni/C was stable during recycling in aqueous ammonia, while Ni/Al2O3 was not due to the formation of AlO(OH).

Treatment of the mononuclear complex [Pd{2,4-(MeO 2 )C 6 H 2 C(H) N(Cy)- C6,N }{(Ph 2 P) 2 C CH 2 - P,P ′}][PF 6 ] ( 1 ) with methyl 2-oxocyclopentanecarboxilate, α-acetylbutyrolactone or methyl phenylsulfonylacetate in the presence of anhydrous sodium carbonate yielded the addition products [Pd{2,4-(MeO) 2 C 6 H 2 C(H) N(Cy)- C6,N }{(Ph 2 P) 2 CHCH 2 C(R 1 )(R 2 )- P,P ′}][PF 6 ] (R 1 = COOCH 3 , R 2 = COCH 2 CH 2 CH 2 , 2 ; R 1 = COCH 3 , R 2 = COOCH 2 CH 2 , 3 ; R 1 = COOCH 3 , R 2 = SO 2 Ph, 4 ) in high yield. The existence of two chiral carbon atoms in the diphosphine moiety produces the existence of optical isomers. Reaction of 1 with acetone and potassium tert-butoxide afforded complex [Pd{2,4-(Me) 2 C 6 H 2 C(H) N(Cy)- C6,N }{(Ph 2 P) 2 CHCH 2 CH 2 COCH 3 - P,P ′}][PF 6 ] ( 5 ), via C–C bond formation. Complex 1 reacts in methanol and in ethanol to give the corresponding addition products [Pd{2,4-(MeO) 2 C 6 H 2 C(H) NCy- C6,N }{(Ph 2 P) 2 CHCH 2 OR- P,P ′}][PF 6 ] (R = CH 3 , 6 ; R = CH 2 CH 3 , 7 ) , via C–O bond formation. Treatment of complex 1 with cyclohexylamine or dimethylhidrazine gives place to [Pd{2,4-(MeO) 2 C 6 H 2 C(H) N(Cy)- C6,N }{(Ph 2 P) 2 CHCH 2 N(H)R– P,P ′}][PF 6 ] (R = C 6 H 11 , 8 ; R = N(CH 3 ) 2 , 9 ), via C–N formation. The crystal structure of 7 has been determined by X-ray crystallography and comprises equimolar amounts of the (C16 R ) and (C16 S ) enantiomers. Reaction of compound 1 with dl -alanine or dl -metionine and anhydrous sodium carbonate yields [Pd{2,4-(MeO) 2 C 6 H 2 C(H) N(Cy)- C6,N }{(Ph 2 P) 2 CHCH 2 NHCH(R 1 )(R 2 )- P,P ′}][PF 6 ] (R 1 = CH 3 , R 2 = COOH, 10 ; R 1 = CH 2 CH 2 SCH 3 , R 2 = COOH, 11 ). Treatment of complex 1 with piperazine give rise to the dinuclear compound [{Pd[2,4-(MeO) 2 C 6 H 2 C(H) N(Cy)- C6,N ]} 2 {(Ph 2 P) 2 CHCH 2 N(CH 2 CH 2 ) 2 NCH 2 CH(PPh 2 ) 2 - P,P,P ′ ,P ′}][PF 6 ] 2 12 , in which each N–H bond of the piperazine has been added to the vinylidene bond of one vdpp ligand.

In order to obtain a gallic acid platinum complex, the title compound was synthesed from cis-[Pt(Cyclohexylamine)]2I2 by the reaction with NH3, silver nitrate and gallic acid respectively. The complex structure and component were characterized by elemental analysis, ESI-MS, 1H-NMR and IR and the anticancer activity was measured by MTT method. The result showed that its structure was consistent with the title compound and had inhibiting effect on the growth of tumor cell lines in vitro.

We prepared the 2-hydroxy-5-trimethylsilylferrocenecarbaldimine systems 13 enantioselectively by a short synthetic route starting from the chiral ferrocene carbaldehyde acetal 5. The imines 13a–c were used to synthesize the zwitterionic (“ferrocene-salaldiminato”)2ZrCl4 complexes 14a–c. Activation with MAO gave homogeneous Ziegler–Natta catalysts, which showed only a moderate ethylene polymerization activity, similar to the unsubstituted parent “ferrocene-salaldiminato” zirconium systems. Consequently, a synthetic route was devised and carried out to make the corresponding 2-hydroxy-3,5-bis(trimethylsilyl)ferrocenecarbaldimines (21) available. The enantiomerically highly enriched ligands (pS)-21a and -d derived from the aldehyde and aniline or cyclohexylamine, respectively, were used to synthesize the corresponding (“ferrocene-salaldiminato”)2ZrCl4 complexes 22a,d. Both gave highly active homogeneous Ziegler–Natta catalysts upon activation with MAO for the formation of linear low molecular weight polyethy...

Syntheses of the original compact molecular systems were developed and the ways of their practical use were examined. A group of new substances was synthesized on the basis of available penta-erythritol bicyclophosphite and thionophosphate, including respective ammonium salts, phosphocholines, a complex compound of molybdenum, and a hydrophosphoryl compound.

A series of salicylaldimine ligands were designed to promote palladium-catalyzed Suzuki–Miyaura cross-coupling reaction. After a screening process, a ligand with a bulky 2,4-di-tert-butyl substituent on the salicyaldehyde backbone and cyclohexylamine moiety was found to serve as a good combination for this reaction in aqueous solutions of DMF. The protocol demonstrated a significant advance in the efficiency of the cross-coupling of aryl bromides and aryl chlorides with arylboronic acids to produce the desired biaryl products. Copyright © 2012 John Wiley & Sons, Ltd.

A pilot-plant process is described for the reduction of 2-allyl cyclohexanone oxime with melted sodium in xylenes, toluene, and 4-methyl-2-pentanol. The trans/cis ratio was 3–4:1. Safety data are presented from a range of thermokinetic experiments (heat flow calorimetry, differential scanning calorimetry, and accelerating rate calorimetry). The process has been designed and developed to enable an expedient and safe scale-up in a standard enameled 100-L steel reactor and has been reproduced six times on 209 mol scale (each 4.8 kg sodium). Crystallization of the product 2-allyl cyclohexylamine with oxalic acid from the reaction mixture in tert-butyl methyl ether successfully avoided the yield losses associated with the isolation of the volatile free 2-allyl cyclohexylamine.

Cyclohexylcarbamodithioic acid has been synthesized by the reaction of cyclohexylamine with carbon disulfide at room temperature. Its complexes have been synthesized by the reaction of cyclohexylcarbamodithioic acid with organotin(IV) chlorides in 1 : 1/1 : 2 molar ratio. The ligand and complexes have been characterized by elemental analysis, infrared (IR), and multinuclear (1H, 13C, and 119Sn) NMR spectroscopy. Elemental data show good agreement between calculated and found values of carbon, hydrogen, nitrogen, and sulfur. IR data show that the ligand is bidentate and complexes exhibit a five-coordinate geometry in the solid state, which is also confirmed by semi-empirical studies. NMR data show that the complexes exhibit tetrahedral geometry in solution state. The ligand and its complexes were screened for their in vitro mutagenic, antimicrobial, MIC, antioxidant activities, and cytotoxicity. Biological screening data demonstrate that complexes show significant activity against various bacterial and fun...

Different organic compounds, o-dihydroxybenzene, m-dihydroxybenzene, p-dihydroxybenzene, glycol, and cyclohexylamine, were used as the extra carbon source for a series of nanoporous carbon (NC) materials prepared by directly carbonizing composites containing citric acid and aluminum phosphate. The effect of the extra carbon source was studied. The structure and surface functional groups on the NC material were different with different extra carbon sources. The NC materials prepared using m-dihydroxybenzene, p-dihydroxybenzene or cyclohexylamine have excellent catalytic activity for the aerobic oxidation of benzyl alcohol to benzaldehyde.

cis-Amminedichlorido(cyclohexylamine)platinum(II) (JM118) is an antitumor Pt(II) analogue of cisplatin exhibiting considerably higher activity than cisplatin in human tumor cells. JM118 is also the major metabolite of the first orally administered Pt(IV) drug satraplatin. In an effort to design improved platinum antitumor agents, it is important to elucidate the biochemical factors that affect the cytotoxic properties of existing platinum drugs. Since DNA is considered the major pharmacological target of platinum drugs, the objective in the present work was to understand more fully the DNA binding mode of antitumor JM118. We examined the rate of aquation of the first chloride of bifunctional JM118 and found that it was considerably lower than that of cisplatin; consequently, the rate of the reaction of JM118 with DNA was lower compared to cisplatin. The influence of global modification by JM118 and its major site-specific adducts on DNA conformation by biochemical methods was investigated as well. While examination of the global modification revealed in several cases no substantial differences in the lesions induced by JM118 and cisplatin, DNA bending due to the 1,2-GG intrastrand adduct of JM118 was lower than that of cisplatin. The bending angles afforded by the adducts of JM118 were only slightly affected by the orientation of the cyclohexylamine ligand toward the 3' or 5' direction of the duplex. We also used in vitro assays that make it possible to monitor DNA repair synthesis by cell-free extracts and DNA-protein cross-linking to probe properties of DNA adducts of JM118. These results showed a higher DNA-protein cross-linking efficiency of JM118 and a less efficient removal from DNA of the adducts of JM118 in comparison with cisplatin. Thus, the results of the present work provide additional evidence that DNA binding of JM118 is in several aspects different from that of conventional cisplatin.

Treatment of (η6-p-cymene)OsCl2(IPr) (1, IPr = 1,3-bis(2,6-diisopropylphenyl)imidazolylidene) with AgBF4 in acetonitrile leads to [(η6-p-cymene)Os(CH3CN)2(IPr)][BF4]2 (2), which reacts with aniline and cyclohexylamine to afford [(η6-p-cymene)Os(dNHR)(IPr)]BF4 (R = Ph (3), Cy (4)). Complexes 3 and 4 have also been prepared by addition of nBuLi to tetrahydrofuran solutions of the amine compounds [(η6-p-cymene)OsCl(NH2R)(IPr)]BF4 (R = Ph (6), Cy (7)). Complex 4 decomposes in tetrahydrofuran at 100 _C and in the presence of H2O to give cyclohexanone, propane, and [η6-p-cymene)Os{CCHCHCHC(iPr)CNCHCHN(C6H3iPr2)C}(NH3)]BF4 (8). In dichloromethane at 50 _C, 4 evolves to [(η6-p-cymene)OsH(NHdCCH2CH2CH2CH2CH2)(IPr)]BF4 (9), which also gives 8 in tetrahydrofuran at 100ºC and in the presence of H2O. On the basis of these transformations, a mechanism for the formation of 8 is proposed., Financial support from the Spanish MICINN (project number CTQ2008-00810 and Consolider Ingenio 2010 CSD2007-00006), the Diputación General de Aragón (E35), and the European Social Fund is acknowledged.

Three Mannich base ligands, Cyclohexylamine-N-methylurea (CHMU), Cyclohexylamine-Nmethylacetamide (CHMAA) and Cyclohexylamine-N-methylacetone (CHMA) and their cobalt(II), nickel(II) and copper(II) complexes were synthesized and chelating properties investigated with the view to determine the coordination modes and the stoichiometric ratio of the metal complexes. The Mannich ligands, CHMU, CHMAA and CHMA were prepared by the reaction of cyclohexylamine, formaldehyde and urea; cyclohexylamine, formaldehyde and acetone; cyclohexylamine, formaldehyde and acetamide respectively at 25°C . They were characterized using infra-red (IR) spectroscopy. Their cobalt(II), nickel(II) and copper(II) complexes were equally prepared and characterized by infrared and UV-Visible spectroscopy. The solubilities of the ligands and their complexes in common solvents were also investigated. All the metal(II) complexes are stable in air and decomposed without melting at temperature >300°C . The infra-red spectra of the ligands show absorption bands in the region 3450-3300cm -1 due to (ʋN-H) stretching vibration and 1644-1636cm -1 due to(amide ʋC=O) stretching frequency in addition to other characteristic bands. These bands experienced significant shift downwards to 3434cm -1 and 1634cm -1 respectively on coordination with the metal ions. The coordination was further confirmed by the appearance of new bands at about (455-534) cm -1 and (600-645)cm -1 which are characteristics of M-N and M-O stretching bands. The coordinating atoms however vary with the metal ion as well as the ligand. With CHMAA, copper(II)ion coordinates through the two nitrogen atoms to form four –membered rings while nickel(II) ion coordinates through the oxygen atom and one of the nitrogen atoms to form six – membered rings. Cobalt(II) ion coordinates through both oxygen and the nitrogen atoms to form four –membered rings. With CHMA, copper(II)ion coordinates through the two nitrogen atoms, nickel(II) ion and cobalt(II) ion coordinate through the oxygen atom and one of the nitrogen atoms to form six – membered rings. The results from the percentage composition of the metals in the complexes of metal-CHMU confirm the preparatory procedure of metal to ligand ratio of 1: 2 (M: L).Thus, the prepared complexes have the general formulae [ML 2 ]. Keywords: Mannich base ligands, synthesis, characterization, metal complexes

Kinetic acidities of arenes, ArH, measured some time ago by hydrogen isotope exchange kinetics with lithium cyclohexylamide (LiCHA) in cyclohexylamine (CHA) show a wide range of reactivities that involve several electronic mechanisms. These experimental reactivities give an excellent Brønsted correlation with equilibrium lithium ion pair acidities (pK(Li)) derived as shown recently from computations of ArLi.2E (E = dimethyl ether). The various electronic mechanisms are well modeled by ab initio HF calculations with modest basis sets. Additional calculations using NH(3) as a model for CHA further characterize the TS of the exchange reactions. The slopes of Brønsted correlations of ion pair systems can vary depending on the nature of the ion pairs.

A number of novel isoquinoline derivatives have been synthesized using the readily obtainable (E)-4-(3,4-dimethoxybenzylidene)-4H-isochromene-1,3-dione, 2 , via the reaction with different nitrogen nucleophiles such as cyanoethanoic hydrazide, cyclohexylamine, 2-aminothiophenol and p -toluenesulfonohydrazide. Furthermore, the reactivity of 2 towards thiophenol, and ethylcyanoacetate has been investigated.

It is shown that reversed-flow micellar electrokinetic chromatography in buffer electrolyte solutions with pH < 2.5 can be used to determine catecholamines and their metabolites. The effect of ion-pair (sodium octane sulfonate) and complexing agent (18-crown-6 and 4,13-diaza-18-crown-6) concentrations on the efficiency and selectivity of the separation of biological amines is studied. Complex formation in the macrocycle-analyte system is quantitatively estimated. An on-line version of preconcentration (sweeping) in the presence of 4 mM of 18-crown-6 and 5 mM of cyclohexylamine introduced into the sample matrix is proposed (the preconcentration factor is 900–1500).

The synthesis and characterisation of eight new octahedral PtIV complexes of the type trans,trans,trans-[Pt(N3)2(OH)2(NH3)(Am)] where Am = methylamine (2), ethylamine (4), thiazole (6), 2-picoline (8), 3-picoline (10), 4-picoline (12), cyclohexylamine (14), and quinoline (16) are reported, including the X-ray crystal structures of complexes 2, 8, and 14 as well as that of two of the precursor PtII complexes (trans-[Pt(N3)2(NH3)(methylamine)] (1) and trans-[Pt(N3)2(NH3)(cyclohexylamine)] (13)). Irradiation with UVA light rapidly induces loss in intensity of the azide-to-PtIV charge-transfer bands and gives rise to photoreduction of platinum. These complexes have potential for use as photoactivated anticancer agents.

The rational selection of the templating agents or structure-directing agents (SDAs) is important for the designed synthesis of open-framework materials with specific channel structures. By utilizing organic amines that are predicted by computer simulations as the templates or SDAs, such as cyclohexylamine (CHA), cyclopentylamine (CPA), and n-propylamine, three new open-framework zinc phosphites, including (C6H14N)2[Zn3(HPO3)4] (ZnHPO-CJ2), (C5H12N)2[Zn3(HPO3)4] (ZnHPO-CJ3), and (C3H10N)2[Zn3(HPO3)4] (ZnHPO-CJ4), have been hydrothermally prepared with desired extra-large 24-ring channels analogous to (C4NH12)2[Zn3(HPO3)4] (ZnHPO-CJ1). Their structures are characterized by single-crystal and powder X-ray diffraction, inductively coupled plasma (ICP), IR, and thermogravimetric analyses. These organic amines predicted based on nonbonding interactions of host–guest show good matching in the space and charge density with the host inorganic framework. As with ZnHPO-CJ1 and other known extra-large micropore mate...

Poly(ethylene terephthalate) (PET) waste materials were depolymerized by propylene glycol (PG) in presence of a novel catalytic system (zinc acetate with cyclohexylamine as a co-catalyst) and the effect of co-catalytic system on glycolysis reaction was compared with that of a commonly used catalytic compound (zinc acetate). The glycolyzed product was reacted with maleic anhydride (MA) and phthalic anhydride (PA) to prepare unsaturated polyester resin. The characteristics of the reaction products in each step were studied by 1H-NMR, FT-IR, GPC and intrinsic viscosity (IV). It was found that the depolymerization of PET bottles in the presence of co-catalytic system proceeded faster compared with zinc acetate-catalyzed reaction. Moreover, in synthesis of unsaturated polyester resins, it was observed that the reaction rate of glycolyzed ingredients prepared by co-catalytic system with anhydrides was higher than that of glycolyzed product made by zinc acetate. It was concluded that cyclohexyleamine has a catal...

A novel and environmentally friendly approach using switchable solvent based liquid phase microextraction (SPS-LPME), followed by UV-vis-spectrophotometric determination has been developed for the preconcentration and determination of mercury. Dithizone was used as a complexing reagent that forms a hydrophobic complex with Hg(II) which was determined spectrophotometrically using a UV-vis spectrophotometer at 574.7 nm. The N,N-Dimethyl-cyclohexylamine/protonated N,N-dimethyl-cyclohexylamine carbonate solvent pair was used as a switchable solvent in the presented work. The average relative standard deviation was 0.8% for five repeated determinations at 1.06 μg L−1 of Hg(II) concentration. Analytical parameter like the limit of detection (LOD), limit of quantification (LOQ) and enhancement factor (EF) were calculated as 0.19 μg L−1, 0.62 μg L−1 and 40, respectively. The accuracy of method was evaluated by analyzing NCS ZC81002B human hair certified reference material. The method was successfully applied to the determination of mercury in water and hair samples with satisfactory results.