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In this work, the solubilities of carbamazepine (CBZ) (form III) in ethyl acetate, methyl acetate, ethylene glycol, chloroform and cyclohexylamine were determined by laser monitoring techniques at pressure above sea level, and the solubility data of CBZ (form III) in different pure solvents were fitted by the Modified Apelblat model and λh model. The result shows that the solubility of CBZ (form III) in five solvents increases as temperature rises, and the solubility in chloroform was the largest. The experimental solubility values of CBZ (form III) in ethyl acetate, methyl acetate, chloroform and cyclohexylamine were in better agreement with the simulated fitting values of the λh model. For ethylene glycol, the σ value was much larger than the other four solvents, and it can be seen from the λh model that ethylene glycol was closer to the ideal solution system than the other four solvents.

Two groups of commercially available Ni- and Pd-based catalysts were used for the direct amination of cyclohexanol (CHOL) with NH3 as aminating agent and in the presence of H2, aiming the selective production of cyclohexylamine (CHA) and aniline. The fresh catalysts were characterized in terms of metal loading, support composition (prevailing SiO2 and Al2O3) and metallic dispersion. Ni-based catalysts revealed to be highly active while Pd-based were more selective towards aniline, however requiring higher temperatures and catalyst loading to reach significant CHOL conversions (from 17 up to 67 %). The activity of the catalysts is intrinsically related to their metallic dispersion regardless the metal loading. The Ni-based catalyst with 46 wt. % of Ni is the most promising once it presents higher turnover frequency (TOF) values, as 10 fold high, particularly related to the ratio of desired to undesired by-products. Moreover, operating conditions considerably affect catalysts’ performance.

Selective hydrogenation of aromatic amines, especially chemicals such as aniline and bis(4-aminocyclohexyl)methane for non-yellowing polyurethane, is of particular interests due to the extensive applications. To conquer the existing difficulties in selective hydrogenation, the Ru0-Ruδ+/CeO2 catalyst with solid frustrated Lewis pairs was developed for aromatic amines hydrogenation with excellent activity and selectivity under relative milder conditions. The morphology, electronic and chemical properties, especially the Ru0-Ruδ+ clusters and reducible ceria were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electronic microscopy (SEM), X-ray photoelectron spectroscopy (XPS), CO2 temperature programmed desorption (CO2-TPD), H2 temperature programmed reduction (H2-TPR), H2 diffuse reflectance Fourier transform infrared spectroscopy (H2-DRIFT), Raman, etc. The 2% Ru/CeO2 catalyst exhibited good conversion of 95% and selectivity greater than 99% toward cyclohexylamine. The volcano curve describing the activity and Ru state was found. Owning to the "acidic site isolation" by surrounding alkaline sites, condensation between the neighboring amine molecules could be effectively suppressed. The catalyst also showed good stability and applicability for other aromatic amines and heteroarenes containing different functional groups.

The high-temperature (HT) and low-temperature (LT) hydrothermal stabilities of molecular-sieve-based catalysts are important for the selective catalytic reduction of NOx with ammonia (NH3-SCR). In this paper, we report a catalyst, Cu2+ loading SAPO-17, synthesized using cyclohexylamine (CHA), which is commercially available and inexpensive and is utilized in NH3-SCR reduction for the first time. After systematic investigations on the optimization of Si and Cu2+ contents, it was concluded that Cu-SAPO-17-8.0%-0.22 displays favorable catalytic performance, even after being heated at 353 K for 24 h and at 973 K for 16 h. Moreover, the locations of CHAs, host–guest interaction and the Bronsted acid sites were explored by Rietveld refinement against powder X-ray diffraction data of as-made SAPO-17-8.0%. The refinement results showed that two CHAs exist within one eri cage and that the protonated CHA forms a hydrogen bond with O4, which indicates that the proton bonding with O4 will form the Bronsted acid site after the calcination.

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.

Graphite oxide (GO) exhibits selective sorption of di-butylamine from a mixture of butylamine, di-butylamine and tri-butylamine. The selectivity is attributed to the higher basicity of di-butylamine in comparison to butylamine and tri-butylamine. Reaction of GO with a mixture of hexylamine and cyclohexylamine, two amines of similar basicity but different structures, suggests that in alkylamines, selectivity is predominantly due to the basicity of the amine with structural differences playing almost no role. However, when GO reacts with a mixture of aniline and cyclohexylamine (amines with a large difference in basicity) no selectivity is observed. The π-π interaction between the aromatic amine, aniline, and the aromatic regions of GO causes the sorption of aniline in its non-protonated form as much as cyclohexylamine with a far higher basicity.

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.

An atom-economic and moderate approach for highly selective one-step catalytic amination of cyclohexene to cyclohexylamine using HZSM-5 with a Si/Al ratio of 38 has been successfully developed in this work. Results showed that 4.3% cyclohexene conversion with 100% selectivity to cyclohexylamine was achieved under optimal reaction conditions. The acid strength of the catalyst played an extraordinarily important role in the present amination reaction. The possible catalytic amination mechanism of cyclohexene with NH3 using HZSM-5 has also been suggested. This approach is a promising process for the preparation of cyclohexylamine from one-step amination of cyclohexene employing commercialized HZSM-5 as an effective and regenerable catalyst under relatively mild conditions.

Hexamethyleneimine (HMI) is used as the structure-directing agent (SDA) in the conventional synthesis method of MCM-49 zeolite. Cyclohexanine (CA) is less toxic and cheaper than HMI. Hence, in this paper, MCM-49 zeolite was successfully synthesized by using CA as a sole SDA with the aid of seeds. Both the seed and template CA are indispensable for the synthesis of MCM-49 zeolite. The optimum synthesis conditions were obtained. The range of the SiO2/Al2O3 ratio of the initial gel was broadened to 70. The synthesis of MCM-49 followed the liquid-phase crystallization mechanism. The MCM-49 zeolites synthesized by using CA and conventional template hexamethyleneimine (HMI) exhibit similar intrinsic properties, such as morphology, acidity, BET surface area, SiO2/Al2O3, and so on. The MCM-49(CA) exhibite good catalytic activity and product distribution in alkylation of benzene with methanol.

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.

In this work, we have synthesized four SAPO-34/44 (framework type code: CHA) samples by utilizing different organic structure-directing agent (OSDA) such as cyclohexylamine (CA), n-butylamine (BA), diisopropylamine (DIPA), and dipropylamine (DPA). An approach combining Rietveld refinement and simulated annealing has been successfully applied to determine the location of the individual OSDA and the host (inorganic framework)-guest (OSDA) interaction. The final Rietveld refinements show that 1) one cha cage can be occupied by either two OSDAs (CA and BA) in the up-and-down arrangement or one OSDA (DIPA and DPA) in the longitudinal configuration and 2) the classical hydrogen bond between CA/BA and the inorganic framework in SAPO-44-CA and SAPO-34-BA could be identified. The host-guest interactions among these four samples are also investigated by FT-IR, which are consistent with Rietveld refinement results. The approach employed here could be applicable for the host-guest investigation in other crystalline porous materials.

Mordenite and ZSM-5 (with MOR and MFI topology, respectively) have been synthesized using cyclohexylamine (CHA) as structure directing agent. The zeolite crystals obtained were characterized by X-ray diffraction (XRD), infrared spectra (IR), Raman spectra, thermal analysis (TG/DTA), elemental analysis (EA) and 13C MAS NMR spectroscopy. It was found that CHA was trapped in the two zeolites in its protonated state together with some other organic species. Furthermore, the oxidation of CHA restricted in zeolites by H2O2 has been studied. The oxidation products of restricted CHA were nitro compound and saturated hydrocarbons in mordenite, whereas nitro compound, cyclanes and amines in ZSM-5. The adsorption tests illustrated that the as-synthesized samples and their oxidized products have high adsorption capacity for Ni (II). This work opens new opportunities for further research of molecular reactions on the inorganic hybrids, and provides a new idea for the application of SDAs present in molecular sieves.

The stoichiometric reactions of amines with tri(4-chlorophenyl)boroxine (CPB) led to the formation of adducts CPB·L {L = morpholine (1a), benzylamine (1b) cyclohexylamine (1c), 2-picoline (1d), 4-picoline (1e), piperidine (1f)} and (CPB)2·(4,4′-trimethylenedipiperidine) (1g). Compounds 1a-1g have been characterized by NMR (11B, 1H, 13C), IR spectroscopy and powder-XRD. VT 1H NMR spectra on 1a and 1d-1g were consistent with a ligand exchange/recombination process and activation energies of 49–58 kJ mol-1 were obtained. The synthesis of [C6H11NMe3][Ph4B3O3] (2) from Ph2BOBPh2, PhB(OH)2 and [C6H11NMe3][OH] in a 1:4:2 ratio in MeOH/H2O is also reported. Compound 2 was characterized by thermal analysis (TGA/DSC), spectroscopy (IR, NMR) and 1a, 1b and 2 were further characterized by single-crystal XRD studies.

Biocatalytic C–H amination is one of the most challenging tasks. C-H amination reaction can hardly be driven efficiently by solely one enzyme so far. Thus, enzymatic synergy represents an alternative strategy. Herein, we report an “Artificially Bioamination Pathway” for C–H amination of cyclohexane as a model substrate. Three enzymes, a monooxygenase P450BM3 mutant, an alcohol dehydrogenase ScCR from Streptomyces coelicolor and an amine dehydrogenase EsLeuDH from Exiguobacterium sibiricum, constituted a clean cascade reaction system with easy product isolation. Two independent cofactor regeneration systems were optimized to avoid interference from the endogenous NADH oxidases in the host E. coli cells. Based on a stepwise pH adjustment and ammonium supplement strategy, and using an in vitro mixture of cell-free extracts of the three enzymes, cyclohexylamine was produced in a titer of 14.9 mM, with a product content of up to 92.5%. Furthermore, designer cells coexpressing the three required enzymes were constructed and their capability of alkane bio-amination was examined. This artificially designed bioamination paves an attractive approach for enzymatic synthesis of amines from accessible and cheap alkanes.

In this study, we synthesized a class of positional isomers by attaching a carboxylic group in different sites (para-, meta- and ortho-position) of an aromatic core. The isomers undergo both aggregation-induced emission (AIE) and intramolecular charge transfer (ICT) mechanisms, as proved by their photoluminescence (PL) behaviour. Changing the position of the carboxylic group will adjust the dipole–dipole direction, which further controls the self-assembled architecture: The morphology undergoes a transition from 1D nanowire to 2D microsheet, and even to 3D microcube. The benzoic acid moiety of the AIE isomers has strong affinity to amines, and adsorbing amines leads to spectral changes including hypochromatic shift and emission quenching. The sensing mechanism was studied by density functional theory (DFT), which reveals that the amine-responsive fluorescence can be ascribed to the weakened ICT effect. A prototype of amine sensor based on m-DB self-assemblies was developed accordingly, showing a remarkable quenching efficiency as high as 85.4%. A linear relation was obtained from the quantitative determination of amine, offering a low detection limit of 2.02 Pa. It can also respond to other organic amines such as diisopropylamine (DIPA), triethylamine (TEA), isopropylamine (IPA) and cyclohexylamine (CHA). Finally, the practicality of the sensor was also demonstrated: When placing the sensing film beside the spoiled meat, the spectrum shows a remarkable fluorescence quenching; in contrast, fresh meat samples have induced a much lower quenching efficiency. This demonstrates that the AIE isomers have a great potential to serve as indicators for meat spoilage.

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.

A series of Ru/NaY catalysts modified by a different amount of polyethylene glycol (PEG) were prepared using the impregnation-precipitation method and tested towards the reaction of paranitrotoluene (PNT) hydrogenation to p-methyl-cyclohexylamine (PMC). The various characterization techniques applied suggested that a suitable amount of PEG was responsible to reduce Ru nanoparticles size and enhance at the same time metallic Ru loading on the catalyst surface. A Ru-PEG7.5/NaY catalyst modified by 7.5 mL PEG showed a higher PNT conversion (> 99.9%) and reaction selectivity to PMC (95.2%) at 160 °C for 35 min compared to other Ru catalysts of different Ru/PEG molar ratio. The reusability of the Ru-PEG7.5/NaY catalyst was also investigated showing only slight deactivation due to Ru agglomeration.

The aza-Michael reaction is the addition of an amine to an electron deficient C=C double bond. This reaction is also used in the synthesis of precursors of polymeric networks. In this study, we paid attention to the kinetics and mechanism of the aza-Michael addition of cyclohexylamine (CHXA) to diethyl maleate (DEM) performed as a solvent-free, catalyst-free reaction and to concurrent reactions. In situ Raman spectroscopy, NMR spectroscopy and gas chromatography/mass spectrometry have shown the occurrence of three simultaneous reactions: (i) the aza-Michael addition of CHXA to DEM leading to diethyl 2-(cyclohexylamino)succinate, (ii) isomerization of DEM to diethyl fumarate (DEF), and (iii) the aza-Michael addition of CHXA to DEF formed by the reaction (ii). All of these reactions proceed with third order kinetics, first order in DEM or DEF and second order in CHXA. We propose a kinetic model that allows kinetic constants to be estimated. Furthermore, a numerical solution of the set of differential equations confirms the expected kinetic equations of reactions (i) and (ii) and gives values of rate constants comparable to the estimated ones. A DFT mechanistic study illustrates the structure of the reaction intermediates and transition states of all reactions and explains the contribution of the second amine molecule in the reaction mechanism.

The FeAPO-44 molecular sieve with CHA-type structure has been synthesized under solvent-free conditions. This is the first case that this material was successfully prepared by this novel solvent-free method. Its optimal synthesis conditions were refined. The results show that proper P2O5/Al2O3 ratio, a lower SDA/Al2O3 ratio (SDA: cyclohexylamine) and relatively mild crystallization temperature are more beneficial to the synthesis of pure CHA phase. The structural and compositional characteristics of the relatively pure FeAPO-44 zeolite were studied in depth by XRD, TG-DSC, CHN element analysis, EDS, SEM and N2 physisorption. According to the CHN element analysis, EDS and TG-DSC measurements, the approximate chemical formula of the synthesized sample SDA/Al-1.4 was determined. The catalytic performances of selected samples were investigated in the methanol-to-olefins reaction. The present results imply that many other zeolite topologies may be conveniently prepared by this solvent-free route.

To understand the effect of molecular structure (cyclic and acyclic) on the corrosion inhibition properties, cyclohexylamine (CHA) and hexyl amine (HA) were investigated as corrosion inhibitors for Carbon Steel (CS) in 2 N hydrochloric acid at 25, 30, and 35°C. Experimental methods like gravimetric, polarization and impedance spectroscopy were used. Different kinetic and thermochemical investigations were made by density functional theory. The IR absorption spectra (theoretical and experimental) were obtained after performing frequency operation on geometry optimized structures of CHA and HA. The type of inhibition provided by CHA and HA was examined by computational and experimental techniques. The adsorption study (theoretical and experimental) shows that the HA molecules adsorb uniformly on CS in a linear chain by forming a stable coordinate covalent bond between Fe (110) surface and N atoms. CHA and HA showed 81.06% and 85.13% corrosion inhibition efficiency, respectively. Linear chain acyclic hydrocarbon i.e., HA was proved to be a better inhibitor than cyclic hydrocarbon, CHA having almost similar molecular formula. The Biochemical and chemical oxygen demand of wastewater was found within the acceptable level.

Cyclohexylamine- N -dithiocarbamate ligand was prepared and used to synthesize Cu complex [Cu(S 2 CNC 6 H 12 ) 2 ]. The effect of capping molecule was studied through the thermolysis of the precursor in hexadecylamine (HDA) and tri-octylphosphine- n -oxide (TOPO) to give HDA and TOPO-capped CuS nanoparticles by varying their concentrations. The absorption spectra showed localized surface plasmon resonances (LSPR) and quantum confinement effect for all samples. TEM micrographs displayed well-dispersed isotropic particles for the sample prepared at higher concentration of HDA and anisotropic particles for the sample prepared at lower concentration which was different with TOPO capped nanoparticles. The synthesized copper sulfide nanoparticles revealed hexagonal phase.

Using Michael addition crosslinking technology, thermoset coatings were prepared from acrylated epoxidized sucrose soyate (AESS) and amine crosslinkers. AESS was synthesized from sucrose soyate, which is the sucrose ester of soybean oil fatty acids and has an average of about 12 functionalities per molecule. Due to the high functionality of AESS and fast reactivity of the amine crosslinkers, the coatings can be cured at ambient temperature (21 °C) in a relatively short period of time yielding good coatings properties. When AESS was reacted with 4′4′-methylene bis(cyclohexylamine), the acrylate group conversion was determined by FTIR to be up to 90%. It was also found that the type of solvent used in the coatings formulation affected the film formation and thus the coatings properties. The addition of 1,6-hexanediol diacrylate diluent in the formulations resulted in softer and lower T g coatings. Using a trifunctional amine such as diethylene triamine, coatings could be prepared without the addition of any catalyst. Overall, thermosets made from AESS Michael crosslinking technology provide a highly bio-based coating system with good hardness and chemical resistance.

Densities and viscosities of the binary system of cyclohexylamine with 2-methylcyclohexanol were measured for the entire composition range at T = 293.15–313.15 K and at the atmospheric pressure. The excess molar volumes, deviations in viscosity, thermal expansion coefficients, and isothermal coefficient of pressure excess molar enthalpy were calculated from the experimental data. These values were negative at all temperatures. The excess molar volumes and deviations in viscosity were fitted with the Redlich–Kister equation to obtain their coefficients and standard deviations. The most stable geometry of 2-methylcyclohexanol … 2-methylcyclohexanol, cyclohexylamine … 2-methylcyclohexanol and cyclohexylamine … cyclohexylamine were studied using the density functional theory in gases phase. To achieve molecular level insight into the behavior in liquid phase, the molecular dynamics simulations have been carried out and used to calculation of the densities, radial distribution functions (RDFs) and mean square displacements (MSD) of the mixtures with different mole fractions at 298.15 K and at 1.0 atm. For these mixtures, using molecular dynamics simulation and quantum calculations, the structural and dynamical hydrogen bonding interactions are considered too. These technics are used to determine the Hydrogen-bonded networks formed by 2-methylcyclohexanol and cyclohexylamine mixture.

The solubility data of the salt of 2-mercaptobenzothiazole with cyclohexylamine (2-MBT-CHA) and tert-butylamine (2-MBT-TBA) in solid-liquid equilibrium, in various alternative solvents, are indispensable for a preliminary industrial application aimed at producing sustainable and renewable materials. In this paper, the solubility behavior of 2-MBT-CHA and 2-MBT-TBA, in various solvents (1,4-dioxane, methyl isobutyl ketone (MIBK), toluene and water) at low temperatures ranging from 303.15 to 348.15 K, has been studied. From the experimental data, it was found that the solubility of 2-MBT-CHA and 2-MBT-TBA increased when temperature increased. In addition, it was found that surface tension and polarity index were strongly dependent on the solubility of 2-MBT-CHA and 2-MBT-TBA. The solubility of 2-MBT-CHA and 2-MBT-TBA is in the following sequence, MIBK,4-Dioxane, toluene and water. To conclude the experimental data, thermodynamic models such as the polynomial empirical, the Van't Hoff, modified Apelblat, the semi-empirical Buchowski–Ksiazczak, the Wilson and the UNIQUAC were investigated. The Wilson model proved to be the most suitable for predicting the solubility behavior of 2-MBT-CHA and 2-MBT-TBA with temperature. Thermodynamic parameters were also investigated. Hence, it was noted that the dissolution process of 2-MBT-CHA and 2-MBT-TBA in investigated solvents is endothermic and spontaneous. The solubility of 2-MBT-CHA and 2-MBT-TBA obtained in solvents in this experiment will provide essential support for 2-MBT-CHA and 2-MBT-TBA industrial design and further theoretical studies.

Several errors in the published paper by Wongkaew and coworkers [Fluid Phase Equilibria 434 (2017) 141–151] are identified. The errors noted include the failure of the calculated curve-fit parameters for the Modified Apelblat model, the van't Hoff model and the empirical polynomial equation in temperature to correctly back-calculate the measured solubility data for the salts of 2-mercaptobenzothiazole with cyclohexylamine (2-MBT-CHA) and tert-butylamine (2-MBT-TBA) dissolved in methyl isobutyl ketone (MIBK), 1,4-dioxane, toluene and water in the temperature range from 303.15 K to 348.15 K. Internal inconsistencies were noted in the reported thermodynamic properties of dissolution, and several errors were noted in the experimental mole fraction solubilities versus temperature graphs.

Excess molar enthalpies, H m E , have been measured using a Tian-Calvet microcalorimeter for the systems CH3(CH2)u-1OH (u = 1,2,3,4,7,10) + cyclohexylamine at 298.15 K and 0.1 MPa. The H m E values are large and negative, indicating the existence of strong interactions between unlike molecules, which is consistent with the also large and negative excess molar volumes, V m E of these solutions, previously measured by us. The contribution from the equation of state term to H m E has been evaluated for the 1-alkanol + cyclohexylamine, or + 1-hexylamine, or + aniline mixtures, and the corresponding excess molar internal energies at constant volumes, U m, V E , determined. It is shown that such contribution is particularly important for the methanol + aniline system, in such way that the excess functions H m E and U m, V E have different sign at x1 = 0.5. The DISQUAC and ERAS models have been applied to the cyclohexylamine systems, and the interaction parameters reported. DISQUAC improves ERAS results on H m E . The latter model describes correctly the V m E curves. The variation of H m E of CH3(CH2)u-1OH + cyclohexylamine, or + 1-hexylamine, or + aniline mixtures with u along a homologous series with a given amine, or with the amine in mixtures with a given 1-alkanol is discussed in terms of the different interactional contributions to H m E .

Herein, catalytic performance of two CuZnAl hydrotalcite derived materials with different Cu content was investigated in continuous hydrogenation of nitrocyclohexane in liquid phase. We have shown that catalytic behavior of these materials depends strongly on Cu content. Activation of the catalyst with lower Cu loading by calcination at 773 K and reduction in 10 %H2/Ar at 673 K led to formation of mainly CuZn alloys surrounded by ZnO phase - highly selective for cyclohexanone (crucial for nylon production). On the other hand, activation of hydrotalcite based material with higher Cu content led to formation of Cu-ZnO core-shell structure with larger Cu nanoparticles - efficient in production of cyclohexylamine – an essential building block in pharmaceutical manufacturing. The proper interpretation of the catalytic results was supported by CuZnAl physicochemical characterization using physisorption analysis, TGA, ICP OES, TPR, H2-TPD, NH3-TPD, CO2-TPD, XRD, including in-situ XPS and TEM measurements.

Cyclohexylamine (CHA) was tested as an anti-pitting and anti-cracking agent for Mild Steel (MS) in 0.1 N H2SO4 using experimental and theoretical techniques. Experimental techniques used are, weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS). The surface study was carried out by Metallurgical Research Microscopy (MRM) and SEM techniques. Molecular Dynamics Simulation (MDS) and Frontier Molecular Orbital (FMO) studies were performed by Density Functional Theory (DFT). The kinetic and thermochemical parameters like hardness, electrophilicity, nucleophilicity, electron-donating and accepting tendency, work function, back donation energy, Proton Affinity (PA), MS/CHA interaction energy, binding energies, etc., were investigated and discussed at length. Frequency calculation on geometry optimized structure of CHA was carried out to obtain theoretical IR spectra. The mechanism of inhibition was investigated both by theoretical and experimental techniques. The maximum corrosion inhibition efficiency (CIE) shown by CHA at 1000 ppm was 81.06%. The electrochemical impedance spectroscopy (EIS) showed an increase in charge transfer resistance with an increase in the concentration of inhibitor justifying the physisorption process. MRM shows an increase in coating thickness with CHA concentration. SEM image shows a decrease in the roughness of MS surface with CHA concentration. The BOD and COD of wastewater were found within the permissible limit.

A novel Bi-based crystalline molecular materials Bi(C2O4)3(NMP)2 (Bi-NMP) have successfully synthesized by the reaction of Bi(NO3)3.5H2O, N-Methylpyrrolidone (NMP) in the solution of methyl alcohol. Structural analysis indicates that the Bi-NMP shows a novel 2D planar structure. The luminescent behavior for the Bi-NMP has been investigated at room temperature. The results have shown that Bi-NMP can be used as a chemical sensor for multifunctional testing such as aliphatic amines and aromatic amines detection, because of its strong fluorescence properties. When detecting cyclohexylamine (CHA), the K was 2.5 × 105 M−1, and the detection limit was 0.99 μM. When detecting m-phenylenediamine(MPD), the Ksv was 5.5 × 103 M−1, and the detection limit was 45.7 μM. When detecting o-phenylenediamine (OPD), the K was 5.4 × 103 M−1, and the detection limit of Bi-NMP was calculated to be 49.9 μM. In particular, for o-phenylenediamine (OPD), Bi-NMP has a unique switching effect. Therefore, Bi-NMP has not only a detection function but also a recognition function for o-phenylenediamine (OPD), m-phenylenediamine (MPD) and p-phenylenediamine (PPD). In addition, white-light emission is achieved through a reasonable tuning proportion by mixing Sm3+ in Bi-NMP.

Treatment of [RuIII(L)(H2O)2](PF6) (1) (L = N,N′-bis(salicylidene)-o-cyclohexyldiamine dianion) with benzylamine, or 2-(aminomethyl)pyridine afforded the paramagnetic Ru(III) compounds [RuIII(L)(NHC(NHCH2R)R)2]PF6 (R = Ph, 2; Py, 4), respectively. The axial arylamidine ligands are in-situ formed from the oxidative coupling of two molecular amines, which represents the first example of direct metal-medicated amine–amine coupling reaction. The coupling reaction is air sensitive, since no similar product is found when the reaction is conducted under Ar. This reaction is also strongly dependent on the structures of substrates. The reaction of 1 with secondary amine pyrrolidine afforded a bis(imine) Ru(III) compound [RuIII(L)(NC4H7)2]PF6 (5), while the reactions of 1 and ethylamine, isopropylamine and cyclohexylamine afforded a series of bis(amine) Ru(III) compounds. The oxidation of these compounds by Ce(IV) have been conducted to investigate the possible role of the metal center in the coupling reaction.

The direct and rapid chiral analysis of methorphan was achieved with excellent sensitivity and selectivity using ultra high-performance liquid chromatography-single quadrupole mass spectrometry (HPLC-SQD) and supercritical fluid chromatography-single quadrupole mass spectrometry (SFC-SQD). The optimized separation of dextromethorphan and levomethorphan by HPLC-SQD was accomplished in under 9 min using a Chirobiotic V2 (2.1 × 250 mm, 5 μm) column with a mobile phase consisting of MeOH/NH 4 OH/HOAc (100/0.02/0.1, v/v/v). The optimal separation by SFC-SQD was achieved in less than 3 min using a Trefoil AMY1 (2.1 × 150 mm, 2.5 μm) column with a mobile phase comprised of CO 2 , 9% MeOH as a co-solvent, and 0.3% cyclohexylamine as a modifier. The limit of detection was 10 ng/mL in the selected ion recording mode for both systems.

Considering the tremendous toxic effect on human well being and environment, the qualitative and quantitative determination of volatile organic amines (VOAs) is of significant importance. In this paper, nanostructures of WO3–SnO2 having large surface area and uniform pore channels were produced using mesoporous silica, SBA-15 as hard template using a nanocasting strategy. Sensors based on mesoporous WO3–SnO2 nanohybrids were fabricated for detection of important biological odor markers including triethylamine, ethylenediamine, ethanolamine, cyclohexylamine gases. The results exhibit that mesoporous WO3–SnO2 are highly sensitive and distinctly selective to triethylamine (TEA). The response (Ra/Rg) of this sensor to 50 ppm TEA was 87 with a fast response and recovery times of 6 and 7 s respectively at the operating temperature of 220 °C. The detection limit can also be as low as 1 ppm-level with a response of 3. Besides, the sensor shows excellent response/recovery and stability in the concentrations ranging from 1 to 500 ppm. These high sensing performances mainly attribute to the formation of unique heterojunction at the WO3–SnO2 interface and the presence of intrinsic high surface area supported by mesopores arrangement, which collectively offers great variation of resistance in air and TEA molecules (heterojunction) alongside facilitating the faster propagation and adsorption/desorption of TEA molecules across the sensor surface (mesoporous structure). Thus, the nanocasted mesoporous material provides an effective and efficient strategy to design new TEA gas sensors.

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 effect of external direct current electric field on the inhibition behavior of cyclohexylamine and sodium nitrite under simulated atmospheric environments with thin electrolyte layers was investigated by surface characterizations and electrochemical measurements. Results confirmed that the vertical electric field from top to bottom increased the inhibition efficiency of cyclohexylamine but decreased that of sodium nitrite. The opposite electric field weakened the inhibition efficiency of cyclohexylamine but enhanced that of sodium nitrite. Surface analysis indicated that the external vertical electric field can affect the migration of inhibitors under thin electrolyte layers.

An efficient and stable Lewis acid catalyst silicic acid (SA)-immobilized AlCl3 (AlCl3-SA) has been successfully prepared by the chemical bonding method in this work. The results indicated that the immobilized 15%AlCl3-SA exhibited excellent catalytic performance and stability in the vapor phase hydroamination of cyclohexene with cyclohexylamine. 58.5% cyclohexene conversion with 98.7% selectivity to dicyclohexylamine was still maintained after running for over 150 h, and the space time yield of dicyclohexylamine was 142.6 mol/h·m3. The developed AlCl3-SA catalyst had the advantages of low cost and long-time stable activity. Maybe this work provides a promising approach for hydroamination of olefins to amines.

The molecular influence on glass transition temperature (Tg) of select model polyamides was investigated by atomistic modeling. These include nylon 6,6, nylon 6,12, a cycloaliphatic polyamide consisting of 4,4′-methylene-bis(cyclohexylamine) and dodecanedioic acid, as well as a corresponding aromatic counterpart consisting of 4,4′-methylenedianiline and dodecanedioic acid. For each model system, all-atom atomistic molecular dynamics simulations were used to discern and differentiate parameters such as free volume, hydrogen bonding, and chain rigidity. Simulations were able to predict the correct trend in Tg, where the model cycloaliphatic polyamide was shown to have the highest Tg followed by the aromatic polyamide. This is presumably due to the greater chain rigidity exhibited by the cycloaliphatic polyamide around the cyclohexyl ring, which was revealed through a calculation of the dihedral rotation free energy barrier associated with the methylene moiety between either the bis-cyclohexyl or bis-phenyl rings, despite the former having a higher extent of free volume.

N,N-bis((1H-pyrazol-1-yl)methyl)(cyclohexyl)methanamine (LA), N,N-bis((1H-pyrazol-1-yl)methyl)-2,6-diethylbenzenamine (LB), N,N-bis((1H-pyrazol-1-yl)methyl)-4-bromobenzenamine (LC), N,N-bis((1H-pyrazol-1-yl)methyl)cyclohexanamine (LD), N,N-bis((1H-pyrazol-1-yl)methyl)(furan-2-yl)methanamine (LE), N,N-bis((1H-pyrazol-1-yl)methyl)-2-methoxyethanamine (LF), and N,N-bis((1H-pyrazol-1-yl)methyl)-3-(methylthio)propan-1-amine (LG) with [CoCl2·6H2O] in ethanol yield a novel series of Co(II) chloride complexes; i.e. [LnCoCl2] (Ln = LA–LG), respectively. The molecular structures of [LnCoCl2] (Ln = LA–LC) and [LnCoCl2] (Ln = LD–LG) exist as monomeric four-coordinated and five-coordinated complexes, respectively. [LnCoCl2] (Ln = LA–LC) showed a distorted tetrahedral geometry involving non-coordination of the nitrogen atom of the N′-substitution amine moiety and the Co(II) centre, resulting in the formation of an eight-membered chelate ring. The geometry at each Co(II) centre in [LnCoCl2] (Ln = LD–LG) were best described as a distorted trigonal bipyramid involving coordination of the nitrogen atom of the N′-substitution amine group and the Co(II) centre. Specifically, a distorted trigonal bipyramid was achieved in [LDCoCl2] through a coordinative interaction of the nitrogen atom of the cyclohexylamine unit and the Co(II) atom with an σ plane of symmetry based on the bond length of Co–Ncyclcohexylamine [2.466(4) A]. Moreover, [LDCoCl2] showed the highest activity for methyl methacrylate (MMA) polymerization in the presence of modified methylaluminoxane (MMAO) at 60 °C and yielded poly(methylmethacrylate) (PMMA) with a high molecular weight (Mw) and narrower polydispersity index (PDI) compared to the other Co(II) complexes. However, all Co(II) complexes produced syndiotactic (PMMA), characterised using 1H NMR spectroscopy, with ca. 0.70.

A spectrophotometric method is developed for the quantitative determination of some primary aliphatic and aromatic amines, i.e., allyl amine, 1,5-diaminopentane, 1,6-diaminohexane, cyclohexylamine, m-aminophenol, benzidine and p-phenylenediamine. The method is based on the interaction between these amines and 2,4-dinitrofluorobenzene (DNFB) reagent. The spectra of the products show maximum absorption that ranged from 355–357 nm and 366–377 nm with molar absorptivities that ranged from 1.086 × 104–6.398 × 104 and 7.566 × 103–1.581 × 104 l/mol cm for aliphatic and aromatic primary amines, respectively. Beer’s law is obeyed in the concentration range of 0.25–8.0, 1.0–10, 0.25–2.50, 1.0–8.0, 2.0–20, 1.0–12.0 and 1.0–10.0 μg/ml for the above mentioned amines, respectively, and the mean percent recoveries ranged between 97.8% and 103.3% with precision (RSD) better than 5.5% for all the amines under study. In addition, the stability constant has been determined and the mechanism is proposed for the DNFB-amine products.

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.

Densities, ρ , kinetic viscosities, ν , and refractive indices, n D , have been measured for (1-heptanol or 1-decanol + cyclohexylamine) systems at T = (293.15 to 303.15) K. The experimental ρ , ν , n D values were obtained using an Anton Paar DMA 602 vibrating-tube densimeter, an Ubbelohde viscosimeter and a refractometer model RMF970, respectively. These data are used to determine a number of derived properties: excess molar volumes, V m E , dynamic viscosities, η , deviations of this magnitude from linear dependence on mole fraction, Δ η , Gibbs energies of activation of viscous flow, Δ G ∗ , deviations of n D from the ideal state, Δ n D , or molar refractions, R m . In addition, (1-alkanol + cyclohexylamine) mixtures have been studied by means of the ERAS model. The corresponding parameters are reported. Viscosity data have been correlated by the following semi-empirical equations: Grunberg–Nissan, Hind, Frenkel, Katti–Chaudhri, Tamura–Kurata, Teja–Rice, McAllister and Heric. The deviations obtained are usually lower than 2%. The large negative V m E values of the studied solutions reveal the existence of strong alcohol-amine interactions. The properties V m E and R m increase with the increasing of the chain length of the 1-alcohol, while Δ η and Δ n D decrease. These variations suggest that interactions between unlike molecules are weakened and dispersive interactions become more important when the alcohol size increases. On the other hand, Δ G ∗ is essentially determined by enthalpic effects. The effect of replacing cyclohexylamine by an isomeric amine, hexylamine (HxA), dipropylamine (DPA) or N,N,N-triethylamine (TEA) in mixtures with a given 1-alkanol is also investigated. It is shown that the strength of the methanol-amine interactions become stronger in the sequence: TEA ≈ cyclohexylamine. The application of the ERAS model to (1-alcohol + cyclohexylamine) mixtures supports these findings. The parameters obtained in this work fit well into the general ERAS treatment of (1-alkanol + amine) systems.

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.

A series of Mannich base type derivatives of Glaucocalyxin A (GLA) were designed and prepared. The cytotoxicity of these compounds was evaluated against six tumor cell lines (SMMC-7721, B16, SGC-7901, A549, KB, HL-60). Most compounds exhibited potent antiproliferative effects with low micromolar IC50 values. Compound 1 with para methyl benzyl amine moiety and compound 16 with cyclohexylamine moiety displayed the highest inhibition efficacy. Significantly, the cytotoxicity of compound 1 was much lower than GLA against the normal human liver cell (HL-7702). The in vitro stability assay revealed that transformation of GLA to Mannich base type derivatives improved the compound stability in rat plasma. Finally, decomposition product analysis supported that compound 1 could act as a prodrug and release GLA in the intracellular environment.

Abstact Densities, viscosities, and speeds of sound of the binary liquid mixtures of N-methyl-2-pyrrolidone (NMP) with cyclohexylamine (CHA), cyclohexanol (CHOL) and cyclohexene (CHE) at temperatures of 303.15–318.15 K are measured over the entire composition range. From the experimental values excess molar volume V m E , deviation in isentropic compressibility Δks, excess free length L f E , deviation in viscosity Δη are computed. The variation with the temperature and concentration is discussed in terms of molecular interactions. All the excess parameters and deviations are fitted to Redlich–Kister polynomial equation to estimate the binary interaction parameters and mean deviation from the regression lines. The sign and magnitude of the computed parameters are discussed to reveal the nature and type of interactions existing between the component molecules in the binary mixtures. Thermodynamic investigations under the present study reveal the strong inter molecular interactions between the unlike molecules in the binary systems of NMP + CHA, NMP + CHOL, whereas in the other binary system NMP + CHE the reverse trend is observed due to dispersion forces. The strength of interaction of CHA, CHOL, and CHE with NMP found to follow the order: CHA > CHOL > CHE. FT-IR studies of these mixtures have been estimated and analyzed to study the interactions between unlike molecules. A good agreement is observed between the excess parameters and FT-IR studies.

A novel series of [(dpca)MX 2 ] (M = Cu, X = Cl; M = Cd, X = Br and M = Zn, X = NO 3 ) complexes were synthesized through the reaction of N , N -di(2-picolyl)cyclohexylamine (dpca) with the corresponding metal starting materials. X-ray crystallographic analysis determined that the metal center in complexes [(dpca)CuCl 2 ], [(dpca)CdBr 2 ] and [(dpca)Zn(NO 3 ) 2 ] showed a distorted 5-coordinated square pyramidal, trigonal bipyramidal, and 7-coordinated pentagonal bipyramidal geometry, respectively, involving coordination of the nitrogen atom of the cyclohexylamine moiety with the metal center. Specifically, the catalytic activity of [(dpca)Zn(NO 3 ) 2 ] (1.04 × 10 5 g PMMA/mol Zn·h) for the polymerization of methyl methacrylate (MMA) in the presence of modified methylaluminoxane (MMAO) at 60 °C was six-fold higher than the reference complex [ZnCl 2 ] (1.73 × 10 4 g PMMA/mol Zn·h).

Introduction Despite the existence of new therapeutic options, breast (BC) and colorectal (CC) cancers remain the leading causes of cancer death and the most commonly diagnosed in worldwide. Studies have reported that imidazole derivates show anticancer, antimicrobial, antibacterial, antifungal and antioxidant activities. Furthermore, recently it has been found that the association between imidazole ligands and copper increases their DNA binding affinity giving potential anticancer activity. Therefore, we synthesised three novel Cu(II) complexes using heterocyclic nitroimidazole derivatives as ligands. The aim of this study is to evaluate the cytotoxic activity of these complexes in two BC and two CC cell lines. Material and methods Nitroimidazole derived ligands containing cyclohexylamine, morpholine and piperidine and the respective Cu(II) complexes were synthesised. MCF-7, HCC1806, LS1034 and WiDr cell lines were cultured and grown in proper conditions. To evaluate the cytotoxic activity of these Cu(II) complexes on four cell lines, MTT colorimetric assay was used. Cells were seeded in 48 well-plates and then were treated with increasing concentrations of the complexes, from 0.5 to 200 µM. After 48 hour of incubation, medium was removed and MTT was added. Two hours later, isopropanol was added in order to dissolve formazan crystals. The absorbance was read at 570 and 620 nm and IC50 (half maximal inhibitory concentration) values determined. Results and discussions Some Cu(II) complexes exhibit anticancer activity in cell lines. Studies show that for the MCF-7 and LS1034 cell lines, the nitroimidazole derived complex containing cyclohexylamine presents IC50 values of 22.2 and 23.9 µM, respectively. For WiDr cell line, the same complex has an IC50 of 50.5 µM. The best IC50 value (2.9 µM) for this complex occurs in the HCC1806 cell line, a chemoresistant BC cell line. Curiously, the complex containing piperidine presents a IC50 of 3.8 µM in HCC1806 cell line, while in the other BC cell line (MCF-7) there is no anticancer activity. The nitroimidazole derived complex containing cyclohexylamine is, consequently, the most promising compound in four cell lines. Conclusion Cu(II) complexes derived from nitroimidazole presented anticancer activity against all cell lines. The complex containing cyclohexylamine revealed to be the most promising, especially in HCC1806, basaloid triple-negative breast cancer, known as therapy-resistant.

In this work, an efficient and benign approach for highly selective preparation of cyclohexanone oxime from the liquid-phase oxidation of cyclohexylamine with dioxygen employing supported WO3/γ-Al2O3 as bifunctional catalyst under solvent-free conditions has been developed. The results demonstrated that the bifunctional supported WO3/γ-Al2O3 catalyst played an important role in the oxidation reaction, and 31.4% of cyclohexylamine conversion and 83.2% of selectivity to cyclohexanone oxime were obtained over 10%WO3/γ-Al2O3. Moreover, the possible reaction pathway over supported WO3/γ-Al2O3 catalyst was suggested. It was confirmed that WO3 acted as activating molecular oxygen and the surface hydroxyl groups of γ-Al2O3 were responsible for the adsorption activation of cyclohexylamine. This method for preparation of cyclohexanone oxime from cyclohexylamine is a promising process employing molecular oxygen as green oxidant and inexpensive WO3/γ-Al2O3 as bifunctional catalyst under mild conditions.

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.

Primary or secondary cyclic amine + alkane mixtures have been investigated in the framework of the ERAS (Extended Real Associated Solution) model. The corresponding ERAS parameters are reported. All the amines considered have the same equilibrium constant (KA = 0.75). Cyclopropylamine, cyclopentylamine, cyclohexylamine and pyrrolidine are characterized by the same enthalpy of self-association ( Δ h A * = − 15 kJ mol − 1 ). Piperidine and hexamethyleneimine show a less negative Δ h A * value (−13 kJ mol−1). Experimental data on excess enthalpies, H m E , volumes, V m E , and isobaric heat capacities, C pm E , reveal the existence of physical interactions and structural effects in the studied solutions. The latter lead to values of self-association of pure amines, Δ v A * , which may depend on the solvent in systems with a given amine. Although the model overestimates the Δ h A * values, the relatively high values of the physical parameters XAB remark the importance of physical interactions. ERAS describes correctly the excess functions H m E , V m E , C pm E and G m E (molar Gibbs energy), and the enthalpy of vaporization of pure amines. Nevertheless, discrepancies with experimental data are found for the concentration dependence of V m E and G m E of some mixtures including cyclic primary amines.

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.