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Organic and inorganic structure-directing agents (SDAs) impact Al distributions in zeolite, but the insights into how SDAs manipulate Al distribution have not been elucidated yet. Herein, the roles of different SDAs such as cyclohexylamine (CHA), hexamethylenimine (HMI), and Na+ in selective Al substitution of MCM-49 zeolite are investigated comprehensively by multinuclear solid-state NMR. The results demonstrate that MCM-49 synthesized with HMI shows relatively more T6 and T7 Al, while more T2 Al is observed using CHA. The formation of T2 Al in both MCM-49(HMI) and MCM-49(CHA) is derived from Na+, while protonated HMIs show bias in incorporation of T6 and T7 Al. Most HMIs are occluded in protonated status, and about half of CHAs are occluded in nonprotonated status. The close spatial proximity between nonprotonated CHAs and Na+ synergistically promotes the formation of zeolite structure, leading to more Na+ ions occluded in the zeolite channel with preferential T2 Al substitution.

[Image: see text] To improve the metabolic stability profile of BMS-741672 (1a), we undertook a structure–activity relationship study in our trisubstituted cyclohexylamine series. This ultimately led to the identification of 2d (BMS-753426) as a potent and orally bioavailable antagonist of CCR2. Compared to previous clinical candidate 1a, the tert-butyl amine 2d showed significant improvements in pharmacokinetic properties, with lower clearance and higher oral bioavailability. Furthermore, compound 2d exhibited improved affinity for CCR5 and good activity in models of both monocyte migration and multiple sclerosis in the hCCR2 knock-in mouse. The synthesis of 2d was facilitated by the development of a simplified approach to key intermediate (4R)-9b that deployed a stereoselective reductive amination which may prove to be of general interest.

A simple and highly efficient method for manufacturing cyclohexanone oxime from solvent-free liquid-phase aerobic oxidation of cyclohexylamine over a glucose-modified TiO2 catalyst had been develop...

Modified UNIFAC (Dortmund) parameters for the interactions of the amino group at cycloaliphatic hydrocarbon with the hydroxyl group or the methanol group were determined by means of literature and our own experimental data. The vapor–liquid equilibria of the three binary systems cyclohexylamine + 2-butanol, cyclohexylamine + 2-methyl-2-butanol, and cyclohexylamine + 1-hexanol were measured isothermally with the dynamic method. The predictions of phase equilibrium data using the new parameter set for the amino group at cycloaliphatic hydrocarbon are compared to the predictions using the amino group at aliphatic hydrocarbon. The improvement of the description of experimental data is shown for binary and ternary systems.

The isothermal vapor–liquid equilibrium data are presented for three ternary systems: octane + cyclohexylamine + cyclohexanol, cyclohexane + cyclohexylamine + cyclohexanol, and toluene + cyclohexylamine + cyclohexanol. The experimental data were determined by the dynamic method in a modified Rock and Sieg circulation still at two different temperatures and reduced pressures. The experimental results were compared with the predictions from both UNIQUAC and NRTL activity coefficient models and the equation of state proposed by Elliott, Suresh, and Donohue (ESD EOS).

The three binary mixtures cyclohexane + benzene, cyclohexanol + phenol, and cyclohexylamine + aniline exhibit qualitatively different vapor-liquid phase behavior, that is, azeotropic with a pressure maximum, azeotropic with a pressure minimum, and zeotropic, respectively. Employing molecular modeling and simulation, the COSMO-SAC model, and a cubic equation of state, the root of these effects is studied on the basis of phase equilibria, excess properties for volume, enthalpy, and Gibbs energy as well as microscopic structure. It is found that cyclohexane + benzene is characterized by more pronounced repulsive interactions, leading to pressure maximum azeotropy and a positive excess Gibbs energy. Functionalizing the aliphatic and aromatic rings with one amine group each introduces attractive hydrogen bonding interactions of moderate strength that counterbalance such that the mixture becomes zeotropic. The hydroxyl groups introduce strong hydrogen bonding interactions, leading to pressure minimum azeotropy and a negative excess Gibbs energy.

By taking advantage of certain features in piperidine 4, we developed a novel series of cyclohexylamine- and piperidine-based benzenesulfonamides as potent and selective Nav1.7 inhibitors. However, compound 24, one of the early analogs, failed to reduce phase 2 flinching in the mouse formalin test even at a dose of 100 mpk PO due to insufficient dorsal root ganglion (DRG) exposure attributed to poor membrane permeability. Two analogs with improved membrane permeability showed much increased DRG concentrations at doses of 30 mpk PO, but, confoundingly, only one of these was effective in the formalin test. More data are needed to understand the disconnect between efficacy and exposure relationships.

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 series of polystyrene (PS)-functionalized basic ionic liquids (BILs) were prepared and used as catalysts for synthesis of disubstituted ureas (DSUs) from amines and carbon dioxide (CO2). The PS-BILs as prepared were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FT-IR) spectroscopy. For investigating the catalytic activities, all PS-BILs were tested in a model reaction of cyclohexylamine (CHA) and CO2 to synthesize dicyclohexylurea (DCU). Poly-2 having branched [bis-imidazolium]/[bis-bicarbonate] was found to show the highest activity for the DCU formation among all PS-BILs catalysts. For a comparison point of view, ceria (CeO2) as a typical catalyst and original Merrifield’s resin (MR) was also applied for the reaction. Reaction conditions were optimized by varying reaction temperature, pressure, reaction time, and amount of catalyst used. Under optimized conditions, reactions of various amines with CO2 to synthesize the corr...

The effects of the organic structure-directing agents (OSDAs) and Na cations for the synthesis of ZSM-5 on the location of Al atom in the framework as well as the acidic and catalytic properties were investigated. To achieve these purposes, ZSM-5 zeolites were synthesized by using four kinds of OSDAs including tetrapropylammonium hydroxide cations, dipropylamine, cyclohexylamine, and hexamethylenimine with or without Na cations. In situ FT-IR spectroscopy using CO as probe molecule was applied to the evaluation of the acid property of the ZSM-5 zeolites. The location of Al atoms was examined by high resolution 27Al MAS and MQMAS NMR techniques. The constraint index (CI) has also been used to estimate the distribution of acid sites in the micropores. The location of acid sites was investigated based on the difference in the transition-state shape-selectivity through the cracking of n-hexane and 3-methylpentane. Furthermore, the cracking of various types of paraffins and the conversion of aromatic compounds...

Alkalizing amines such as cyclohexylamine and dimethylamine have great potential for protecting steam–water cycles against corrosion, but their thermal stability is limited and anionic decomposition products are a concern because of increased corrosion risk. In this study, morpholine, ethanolamine, cyclohexylamine, dimethylamine, and 3-methoxypropylamine were exposed to temperatures of 500, 530, and 560 °C at pressures of 9.5, 13.5, and 17.5 MPa to investigate the effects of temperature and pressure on amine thermolysis kinetics. The surface/volume ratio of the reactor tube was 0.4 mm–1, close to the value for superheater tubes in steam–water cycles. All amines thermolyzed by first-order kinetics, with the exception of dimethylamine. The Arrhenius constants Ea, ln(A), and Va were obtained from the experimental data for all investigated amines. The effect of pressure on the thermolysis kinetics was less pronounced than in previous studies and was different for each amine. Dimethylamine did not degrade belo...

Humidity control is required in all health care facilities. Direct injection of steam from a central boiler plant is the most economical humidification system. The steam carries neutralizing amines—corrosion-inhibiting chemicals—that are added to boiler feedwater to prevent pipe corrosion. When the steam condenses, the amines neutralize the resulting carbonic acid and raise the pH of the condensate, which helps reduce, slow down, or prevent corrosion to the condensate system. This technical review compares the use of ‘clean steam’ to ‘utility’ steam and discusses the health effects, regulation, and control of three of the most commonly used amines in ‘utility’ steam: morpholine, cyclohexylamine (CHA), and diethylaminoethanol (DEAE) to make the point that proper application, control, monitoring and oversight of amines in a ‘utility’ steam system of a health care facility is safe, feasible and economical.

Reactions of Fischer alkoxycarbene complexes [W(CO)5{C(OEt)Ar}] (Ar = 2-thienyl (1), 2-furyl (2)) with ethylenediamine led to the formation of two different reaction products: an aminolysis product (5 or 6) where the ethoxy substituent of the carbene ligand is replaced by the ethylenediamine moiety and a chelated product where aminolysis and substitution of one carbonyl ligand had taken place, yielding 7 or 8. Aminolysis of 1 and 2 with cyclohexylamine (CHA) produced the aminocarbene complexes 3 (Ar = 2-thienyl) and 4 (Ar = 2-furyl). Complexes 1–8 have been electrochemically investigated by means of cyclic voltammetry. The relative shifts in the oxidation and reduction potentials are discussed and related to density functional theory (DFT) calculated energies. DFT calculations further show that the oxidation center is located on the metal and the carbonyl groups, while the reduction center is localized on the carbene moiety and is strongly influenced by the electronic properties of its substituents. Cryst...

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...

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.

The mechanism of cross-coupling reactions of aryl halides PhX (X = I, Br, Cl) with cyclohexylamine catalyzed by CuI associated with a diketonate ligand (ket = 2-acetylcyclohexanoate) has been investigated via DFT. Phenyl halides which can be involved in halogen-bond formation (X = I, Br) with the anionic nitrogen of the intermediate [(ket)Cu-NHCy]− can undergo intramolecular oxidative addition, which is in competition with the classical oxidative addition three-centered pathway, whereas those which cannot (X = Cl) undergo a classical oxidative addition, leading to the common complex (ket)CuIIIPh(NHCy). The latter is involved in a faster reductive elimination, leading to PhNHCy. C6F5I, which involves the strongest C6F5I- - -N halogen bond, generates the anion C6F5– and consequently not the expected C–N cross-coupling product by substitution at the C–I bond, as evidenced experimentally.

Cyclic amine or morpholine + organic solvent mixtures have been investigated in terms of DISQUAC and of the Kirkwood–Buff formalism. The amines considered are cyclohexylamine; (c-CH2)uNH (u = 2–7) and (c-CH2)uN–CH3 (u = 4,5). The organic solvents are alkanes and methanol or ethanol. The DISQUAC interaction parameters are reported. The model describes correctly a whole set of thermodynamic properties: vapor–liquid equilibria (VLE); excess Gibbs energies, GmE; excess enthalpies, HmE; excess heat capacities at constant pressure, CP,mE; and partial excess enthalpies at infinite dilution, H1E,∞, as well as the main features of the Kirkwood–Buff integrals. In (c-CH2)uNH + C6H12 mixtures, amine–amine interactions become weaker with increased u values. This is supported by the corresponding decrease of HmE and H1E,∞ and of the effective dipole moment. Interactions between amine molecules are also weakened when passing from a primary cyclic amine to an isomeric tertiary cyclic amine. The existence of an aromatic r...

The experimental data of the tertiary 2-methyl-2-propanol + cyclohexylamine + n-heptane (densities rho and refractive indices nD data) and three binary systems: 2-methy1-2-propanol + cyclohexylamine (n(D) data). 2-methyl-2-propanol + n-heptane (rho and n(D) data), and cyclohexylamine + n-heptane (n(D) data) have been determined. Experimental rho and n(D) measurements have been performed simultaneously, at five temperatures, (303.15, 308.15, 313.15, 318.15 and 323.15) K, and atmospheric pressure, using an Anton Paar DMA 5000 digital vibrating-tube densimeter, with a refractometer Anton Paar RXA 156. Excess molar volumes V-E and deviations of refractive indices Delta n(D) were correlated by the Redlich-Kister equation for binary mixtures and the Nagata-Tamura equation for the ternary mixture.

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.

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.

The excess molar volumes (VE) and viscosity deviations (Δη) have been calculated from experimental density (ρ) and viscosity (η) data of the binary mixtures of 1,3-dioxolane (DO) with 2-methoxyethanol (ME), 2-ethoxyethanol (EE), 2-butoxyethanol (BE), 2-propylamine (PA), and cyclohexylamine (CA) measured over the entire range of composition at 298.15 K. Moreover, deviations in isentropic compressibility (ΔKS) and molar refraction (ΔR) have been calculated from ultrasonic speed of sounds (u) and refractive indices (nD) of the mixtures, respectively. The excess or deviation properties were fitted to the Redlich−Kister polynomial equation to derive the adjustable parameters (Ak) and corresponding standard deviations (σ).

The influence of order of the impregnation of NiO and MoO3 on the structure and catalytic behavior of H-AlMCM-41 supported Ni−Mo catalysts for hydrodenitrogenation (HDN) has been investigated. These catalysts were well characterized by TEM, XRD, N2 adsorption−desorption, XPS, and FT-IR spectra of CO adsorption and tested for hydrodenitrogenation (HDN) of o-toluidine and cyclohexylamine. It was found that the catalyst prepared by sequential impregnation of NiO and MoO3 was more active than the catalyst prepared by coimpregnation. Among the sequentially impregnated catalysts, the catalyst in which NiO deposited first followed by MoO3 shows high HDN activity. TEM, FT-IR spectra of CO adsorption, and estimation of total sulfur of sulfide catalyst results clearly show that the NiO and MoO3 are well dispersed over H-AlMCM-41 on reverse order impregnated catalyst. The very low activity of coimpregnated catalyst is attributed to poor dispersion of metal oxides as well as due to the formation of stable stoichiomet...

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...

Seven new metal–organic frameworks (MOFs) have been synthesized using different organic amines as templates: [Cd(HBTC)2]·2(HDETA)·4(H2O) (1) (BTC = 1,3,5-benzenetricarboxylate and DETA = diethylenetriamine), [Cd2(BTC)2(H2O)2]·2(HCHA)·2(EtOH)·2(H2O) (CHA = cyclohexylamine) (2), [Cd5(BTC)4Cl4]·4(HTEA)·2(H3O) (TEA = triethylamine) (3), [Cd3(BTC)3(H2O)]·(HTEA)·2(H3O) (4), [Zn(BTC)(H2O)]·(HTPA)·(H2O) (TPA = tri-n-propylamine) (5), [Cd(BTC)]·(HTPA)·(H2O) (6), and [Cd2(BTC)(HBTC)]·(HTBA)·(H2O) (TBA = tri-n-butylamine) (7). Topologically, the polymer 1 exhibits a two-dimensional (2D) Cd-HBTC network with (44) topology, which is a sql structure; the polymer 2 possesses a three-dimensional (3D) porous Cd-BTC framework with (4·62)2(42·610·83) topology, which is a contorted rutile structure; polymer 3 exhibits a 3D open Cd-BTC architecture with (62·82·102)2(62·84)(63)4 topology; polymer 4 is a 3D porous Cd-BTC network with new (4·62)2(42·64·86·103)(6·82)2(62·84)(62·84)2(62·8)2 topology; similar to 1, polymer 5 is a 2...

A series of iron(III) complexes of the type [Fe(L)Cl3], where L is the variously N-alkyl-substituted bis(pyrid-2-ylmethyl)amine ligand such as bis(pyrid-2-ylmethyl)amine (L1), N,N-bis(pyrid-2-ylmethyl)methylamine (L2), N,N-bis(pyrid-2-ylmethyl)-n-propylamine (L3), N,N-bis(pyrid-2-ylmethyl)-iso-butylamine (L4), N,N-bis(pyrid-2-ylmethyl)-iso-propylamine (L5), N,N-bis(pyrid-2-ylmethyl)cyclohexylamine (L6), and N,N-bis(pyrid-2-ylmethyl)-tert-butylamine (L7), have been isolated and characterized by elemental analysis and spectral and electrochemical methods. The crystal structures of the complexes [Fe(L2)Cl3] 2, [Fe(L3)Cl3] 3, and the complex-substrate adduct [Fe(L5)(TCC)(NO3)] 5a, where TCC2- is the tetrachlorocatecholate dianion, have been determined by single-crystal X-ray crystallography. The complexes [Fe(L2)Cl3] 2 and [Fe(L3)Cl3] 3 possess a distorted octahedral geometry, in which the linear tridentate 3N ligands are cis-facially coordinated to the iron(III) center, and three chloride ions occupy the remaining coordination sites. The replacement of the N-methyl group in 2 by N-n-propyl group as in 3 leads to the formation of the Fe-Npy bonds and also the Fe-Cl bonds located trans to them of different lengths. The catecholate adduct 5a also possesses a distorted octahedral geometry, in which the ligand is cis-facially coordinated to iron(III) center, TCC2- is asymmetrically chelated trans to the two pyridyl moieties of the ligand, and one of the oxygen atoms of the nitrate ion occupies the sixth coordination site. All of the present complexes have been interacted with simple and substituted catechols. The catecholate adducts [Fe(L)(DBC)Cl] and [Fe(L)(DBC)(Sol)]+, where H2DBC is 3,5-di-tert-butylcatechol and Sol=H2O/CH3CN, have been generated in situ, and their spectral and redox properties and dioxygenase activities have been studied in dimethylformamide and dichloromethane solutions. All of the complexes catalyze the cleavage of H2DBC using molecular oxygen to afford both intra- and extradiol cleavage products. The formation of extradiol cleavage products is facilitated by cis-facial coordination of the 3N ligands and availability of vacant coordination site on iron(III) center for dioxygen binding. It is remarkable that the nature of the N-alkyl substituent in 3N ligands controls the regioselectivity of cleavage, with the n-propyl, iso-butyl, iso-propyl, and cyclohexyl groups enhancing the yield of extradiol products (46-68%) in dichloromethane. The rate of oxygenation depends upon the solvent and the Lewis acidity of iron(III) center as modified by the sterically demanding N-alkyl groups-length and degree of substitution. The plot of log (kO2) versus energy of the low-energy DBC2--to-iron(III) LMCT band is linear, demonstrating the importance of the Lewis acidity of the iron(III) center in dictating the rate of the dioxygenase reaction.

Two Wertheim-based association models, the simplified PC-SAFT and the Elliott-Suresh-Donohue (ESD) equation of state, are compared in this work for the description of vapor−liquid equilibria (VLE) and liquid−liquid equilibria (LLE) in binary systems of aniline, cyclohexylamine (CHA), hydrocarbons, and water. Furthermore, the predictive capabilities of the models are investigated for four ternary systems composed of these components, which exhibit complex liquid−liquid(−liquid) equilibria (LLLE). Various aspects of association models which have an influence in the results are studied for the PC-SAFT equation of state, e.g., the choice of various association schemes for the amines and parametrization of water as well as different approaches for describing solvation. It is shown that simplified PC-SAFT using water parameters estimated in this work can describe successfully water−alkane LLE. In general, both models perform overall similarly for the binary systems, although ESD shows a remarkably good behavior...

Recommended data for the limiting activity coefficients ( ) of nitrobenzene, aniline, and cyclohexylamine in water were established as a function of temperature by the simultaneous correlation of the values resulting from specialized vapor−liquid equilibrium measurements and related thermal data for highly dilute solutions. The new values of were determined by the Rayleigh distillation, circulation still, and headspace analysis methods. The limiting partial molar excess heat capacities were derived from measurements by the Picker flow microcalorimetry. These values were combined with all available literature data on the limiting activity coefficients and the limiting partial molar excess enthalpies. This allowed us to produce a thermodynamically consistent fit of between 273 K and 373 K, which was in turn used in combination with pure solute vapor pressures to calculate the Henry's law constants (kH).

The determination of the structures and DNA interactions and the reactions with GSH and ubiquitin of complexes of the general formula trans-[PtCl2(Am)(pip-pip)] x HCl, where pip-pip is 4-piperidinopiperidine and Am is NH3, methylamine (MA), dimethylamine (DMA), n-propylamine (NPA), isopropylamine (IPA), n-butylamine (NBA), or cyclohexylamine (CHA), were performed. X-ray structures and NMR studies of the NH3 and MA complexes showed that both pip rings were in the chair conformation and that the second pip ring is fluxional. The DNA binding studies showed that these complexes bind to calf thymus DNA nearly an order of magnitude more quickly than cisplatin and form covalent adducts that stabilize the double helix. The binding of the pip-pip complexes to DNA results in high unwinding angles (approximately 30 degrees) and in the formation of approximately 25% interstrand cross-links. The pip-pip complexes reacted with GSH more quickly than cisplatin and transplatin, and the rate of reaction decreased with increasing steric bulk of the ligand trans to the pip-pip. The reactions with ubiquitin resulted in monofunctional binding to Met1. Only the NH3, MA, and DMA complexes reacted with ubiquitin in a slower and less efficient fashion than cisplatin.

Four ternary liquid−liquid(−liquid) equilibria in the systems aniline + cyclohexylamine (CHA) + water, aniline + CHA + octane, aniline + water + octane, and aniline + water + toluene under atmospheric pressure at (298.15 and 333.15) K are reported. The measurements were carried out by turbidity titration, gas−liquid chromatography analyses, Karl Fischer, and potentiometric titration. Predictions of the NRTL and UNIQUAC Gibbs energy models are shown based only on binary parameters of simultaneous fitting of available vapor−liquid equilibria and liquid−liquid equilibria data. In this context P−x data were measured for the system aniline + octane at 383.15 K.

Liquid−liquid equilibria and liquid−liquid−liquid equilibria were determined for (water + cyclohexylamine + toluene), (water + cyclohexylamine + propylbenzene), (water + cyclohexylamine + heptane), and (water + cyclohexylamine + octane) at temperatures of (298.15, 303.15, and 333.15) K at atmospheric pressure by photometric turbidity titration. The composition of conjugate phases was determined by gas−liquid chromatography or potentiometric titration and Karl Fischer titration. All systems show type I behavior since there is only one binary pair of partial miscible liquids. Surprisingly, the systems (water + cyclohexylamine + heptane) and (water + cyclohexylamine + octane) have a three-phase region in a limited temperature range. The data were predicted with the NRTL and the UNIQUAC models in comparison to the Elliott−Suresh−Donohue equation of state based on binary interaction parameters only.

Hydrogenation of aniline to cyclohexylamine was studied in a gas−liquid−liquid−solid tetraphase system using cyclohexane and water as two immiscible liquid phases and ruthenium on alumina (2% Ru/Al2O3) as the catalyst. In addition to the higher catalytic activity with respect to the conventional three-phase system, the novel four-phase system was highly efficient in catalyst−product separation. Experimental data on concentration−time as well as hydrogen-consumption−time profiles were obtained to study the effect of concentration of aniline, catalyst loading, and the partial pressure of hydrogen. A detailed analysis of gas−liquid, liquid−liquid, liquid−solid, and intraparticle mass transfer was carried out using initial rate data to ensure the kinetic regime. On the basis of these data, several rate equations were evaluated to select a kinetic model. The kinetic parameters were estimated over a temperature range of 378−418 K by fitting the integral batch reactor data. A rate model considering adsorption of...

Kinetic acidities are reported for methane, ethane, propane, cyclopropane, isobutane, neopentane, tetramethylbutane, norbornane, nortricyclene, and adamantane by tritiodeprotonation or deuteriodeprotonation in cyclohexylamine catalyzed by cesium cyclohexylamide.

The hydrolysis process of the anticancer drug cis-amminedichlorocyclohexylamineplatinum(II) (JM118 or cis-[PtCl2(NH3)cyclohexylamine]) and the influence of solvent models therein have been studied using hybrid density functional theory (B3LYP). The aquation reactions leading to the activated drug forms a key step for the reaction with the target DNA. In this study, the stepwise hydrolysis, cis-[PtCl2(NH3)cyclohexylamine] + 2 H2O --> cis-[Pt(NH3)cyclohexylamine(OH2)2]2+ + 2 Cl- was explored, using three different models. Implicit solvent effects were incorporated through polarized continuum models. The stationary points on the potential energy surfaces for the first and second hydrolysis steps, proceeding via a general S(N)2 pathway, were fully optimized and characterized. It was found that the explicit solvent effects originating from the inclusion of extra water molecules into the system are significantly stronger than those arising from the bulk aqueous medium, especially for the second aquation step, emphasizing the use of appropriate models for these types of problems. In comparison with previous work on the parent compound cisplatin, a slower rate of hydrolysis is determined for the first (rate determining) reaction. The results furthermore imply that the doubly aquated form of JM118 will be the main DNA binding form of the drug. The results provide detailed energy profiles for the mechanism of hydrolysis of JM118, which may assist in understanding the reaction mechanism of the drug with the DNA target and in the design of novel Pt-containing anticancer drugs.

A detailed study on bromination and subsequent imidization of perylene bisanhydride with cyclohexylamine is reported. The present results reveal that previously reported 1,7-difunctionalized perylene bisimides are presumably contaminated with the respective 1,6 regioisomers. N,N'-Dicyclohexyl-1,7-dibromoperylene bisimide 1,7-3 is obtained for the first time in isomerically pure form, and its structure is unequivocally confirmed by X-ray analysis. By using regioisomerically pure 1,7-dibromoperylene bisimide 1,7-3, 1,7-dipyrrolidinylperylene bisimides 4a-c and 1,7-dipyrrolidinylperylene bisanhydride 5 as well as the unsymmetrically difunctionalized 1-bromo-7-pyrrolidinyl- and 1-cyano-7-pyrrolidinylperylene bisimides 7 and 8 are synthesized in good yield.

The reactions of single-walled carbon nanotubes (SWNTs) with succinic or glutaric acid acyl peroxides in o-dichlorobenzene at 80-90 degrees C resulted in the addition of 2-carboxyethyl or 3-carboxypropyl groups, respectively, to the sidewalls of the SWNT. These acid-functionalized SWNTs were converted to acid chlorides by derivatization with SOCl(2) and then to amides with terminal diamines such as ethylenediamine, 4,4'-methylenebis(cyclohexylamine), and diethyltoluenediamine. The acid-functionalized SWNTs and the amide derivatives were characterized by a set of materials characterization methods including attenuated total reflectance (ATR) FTIR, Raman and solid state (13)C NMR spectroscopy, transmission electron microscopy (TEM), and thermal gravimetry-mass spectrometry (TG-MS). The degree of SWNT sidewall functionalization with the acid-terminated groups was estimated as 1 in 24 carbons on the basis of TG-MS data. In comparison with the pristine SWNTs, the acid-functionalized SWNTs show an improved solubility in polar solvents, for example, alcohols and water, which enables their processing for incorporation into polymer composite structures as well as for a variety of biomedical applications.

Magnesocene amine adducts were prepared and characterized. Addition of primary (3-amino-2,4-dimethylpentane, isopropylamine, tert-butylamine, benzylamine, cyclohexylamine) and secondary (diethylami...

Two fluorinated gallium phosphates, Ga4(PO4)4F1.33(OH)0.67·1.5NC5H12·0.5H3O·0.5H2O (ULM-16) and Ga9(PO4)8F7.3(OH)0.2·4NC5H12·0.5H3O·3.5H2O (MIL-46), have been hydrothermally synthesized by varying the fluorine amount in the presence of cyclopentylamine as structure-directing agent (at 180 °C for 3 days). Their structures were determined by means of single-crystal X-ray diffraction. The first compound (obtained with low fluorine concentration) is isostructural to the gallium phosphate ULM-16 previously prepared with cyclohexylamine. Its three-dimensional framework is built up from the connection by corner sharing of the hexameric units Ga3(PO4)3F2 together with the tetramer Ga2(PO4)2 and consists of channels bound by 16 polyhedra inserting the protonated cyclopentylamine. The second phase (prepared with high fluorine concentration) exhibits a new three-dimensional topology based on the condensation by corner sharing of the identical hexameric building block Ga3(PO4)3F2 with a pentameric species Ga3(PO4)2F4...

Atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI), together with tandem mass spectrometry (MSn), are used to study the mechanism of chlorination of amines and to develop a method for qualitative and quantitative determination of organic chloramines. Cyclohexylamine and 1,4-butanediamine (putrescine) are used as model compounds to investigate the mechanisms of the reactions between primary aliphatic amines and hypochlorous acid (aqueous Cl2). The chlorination products are identified and characterized by collision-induced dissociation (CID) and H/D exchange. Chlorination occurs by electrophilic addition of Cl+ and may be followed by HCl elimination, hydrolysis, or, in the case of diamines, amine elimination by intramolecular nucleophilic substitution. The relative rates of chlorination at amine and chloramine nitrogens are a function of pH and depend on the basicity of the amine. A novel method for active chlorine quantification using ESI or APCI mass spectrometry is suggested on the basis of the extent of chlorination of a sacrifical amine standard. This measurement has a limit of detection for N-chlorocyclohexylamine in the range of 0.1-10 microM, a linear dynamic range of 10(2)-10(3), and an accuracy of +/-10%, as determined for wastewater samples.

In this report we have shown that the commercially available Co(2)(CO)(8) and Co(4)(CO)(12), and enyne--Co(2)(CO)(6) complexes, are sufficiently effective in catalyzing the Pauson--Khand reaction under one atmosphere of CO pressure. It was further demonstrated that the efficiencies of these cyclization protocols could be enhanced by the presence of cyclohexylamine. These procedures have also rendered more practical and highly convenient alternatives for the catalytic Pauson--Khand reaction. Most importantly, we have dispelled the common belief that Co(4)(CO)(12) is inactive in the Pauson--Khand reaction under one atmosphere of carbon monoxide. Of mechanistic importance is that these studies have also shown that the probable formation of Co(4)(CO)(12) is not necessarily a dead end pathway in the Co(2)(CO)(8)-catalyzed Pauson--Khand reaction. It is also of interest that substoichiometric amounts of Co(2)(CO)(8), in DME and in the presence of cyclohexylamine, are sufficient for the cyclocarbonylation of enynes under a nitrogen atmosphere. Our findings have provided more practical protocols for the Pauson-Khand reaction using catalytic amounts of cobalt carbonyl complexes and a better understanding of the influence of Lewis bases on their efficiency. These reports on the activity of Co(4)(CO)(12) are anticipated to develop into a convenient and practical alternative for Co(2)(CO)(8) catalysis.

Treatment of (6S,7S)-7-bis(tert-butyldimethylsiloxy)non-1-en-8-ynes with dicobalt octacarbonyl gave the corresponding cobalt complex. This complex was subsequently exposed to the Pauson-Khand conditions in the presence of a promoter such as cyclohexylamine, thioanisole, methyl isopropyl sulfide, and butyl methyl sulfide ending up with the stereoselective production of the (2S,3S,6S,7S)-7-methylbicyclo[4.3.0]nonenone derivatives instead of the expected (2S,3S,7S)-bicyclo[5.3.0]decenone species.

Synchrotron-based high-resolution photoemission has been used to study the interaction of thiophene, pyridine, and cyclohexylamine (CHA) with pure and Ni-promoted MoSx films and S/Mo(110) surfaces. The MoSx films exhibit Mo 3d and valence spectra that are very similar to those of MoS2. On the MoSx systems, the behavior of thiophene closely resembles that seen on MoS2(0002). The molecules are weakly chemisorbed, and most of them desorb at temperatures around 200 K. A small fraction of the adsorbed thiophene is bonded to Mo sites that have S vacancies and desorbs between 250 and 300 K. A similar behavior is observed for adsorbed pyridine. In contrast, CHA displays a rich chemistry on these surfaces. Mo centers that have a limited number of S vacancies and do not do chemistry with thiophene, pyridine, or H2 are able to cleave the C−N bond in a nonaromatic H-rich molecule like CHA. The addition of Ni enhances the chemical activity of MoSx. On the NiMoSx systems, the adsorption energies of thiophene and pyridi...

The reactions of chlorocyclophosphazenes N3P3Cl6 (1) and N4P4Cl8 (2) and polydichlorophosphazene (3) with cyclohexylamine, cyclopentylamine, and cyclopropylamine have been studied. The major product with 1 is the geminal tetrakis derivative N3P3Cl2(NHR)4, while 2 gives the completely substituted derivative, N4P4(NHR)8. X-ray crystal structure determinations of N3P3Cl2(NHC6H11)4 (1a) and N4P4(NHC3H5)8 (2c) have been carried out. 1a crystallizes in a triclinic space group, P1, with a = 11.2330(13) A, b = 11.4269(16) A, c = 13.4055(12) A, α = 72.211(10)°, β = 72.150(9)°, γ = 81.777(11)°, V = 1557.3(3) A3, and Z = 2. 2c crystallizes in a monclinic space group, P21/n, with a = 12.433(3) A, b = 20.484(4) A, c = 12.645(3) A, β = 92.81(2)°, V = 1557.3(3) A3, and Z = 4. The cycloalkylamino-substituted polyphosphazenes contain a small amount of residual chlorine atoms. These have high glass transition temperatures.

A series of PtIV anticancer complexes with chloro leaving groups have been investigated for the effects of axial and carrier ligands on the reduction and cytotoxicity. The reduction rates of the PtIV complexes such as Pt(d,l)(1,2-(NH2)2C6H10)Cl4 (tetraplatin, Pt(dach)Cl4; dach = diaminocyclohexane), cis,trans,cis-[Pt((CH3)2CHNH2)2(OH)2Cl2] (iproplatin, Pt(ipa)(OH)2Cl2; ipa = isopropylamine), cis,trans,cis-[Pt(NH3)(C6H11NH2)(OCOCH3)2Cl2] (JM-216, Pt(a,cha)(OCOCH3)2Cl2; a = ammine, cha = cyclohexylamine), cis,trans,cis-[Pt(NH3)(C6H11NH2)(OCOC3H7)2Cl2] (JM-221, Pt(a,cha)(OCOC3H7)2Cl2), cis,trans,cis-[Pt(en)(OH)2Cl2], Pt(en)Cl4 (en = ethylenediamine), cis,trans,cis-[Pt(en)(OCOCH3)2Cl2], and cis,trans,cis-[Pt(en)(OCOCF3)2Cl2] by ascorbate and cathodic reduction potentials strongly depend on the electron-withdrawing power and the steric hindrance of the axial and carrier ligands. Beginning with PtIV complexes bearing en carrier ligands, reduction rates and reduction potentials increase in the following order of...

Relative partition coefficients between aqueous methanol and pentane of the two stereoisomers of a series of 4-tert-butylcyclohexylamines were measured by NMR. The cis isomer shows a larger partition coefficient, with a ΔΔG°org→aq up to 1.4 kcal/mol. A thermodynamic cycle relates these values to a solvent dependence of the A value for conformational equilibrium of an amino substituent. The variation with stereoisomer is attributed to a greater hydrophilicity of a cyclohexylamine with an equatorial amino group, or equivalently to a greater steric bulk of an amino group whose lone pair is hydrogen bonded to water. The strong dependence on solvent inferred for ANMe2 was confirmed by direct measurement of conformer populations at low temperature.

The ability of photogenerated amine catalysts to effect the insolubilization of polymers containing acidic methylene units is explored. Cross-linking of films of poly(2-acetoacetoxyethyl methacrylate)-co-(methyl methacrylate) or poly(2-cyanoacetoxyethyl methacrylate)-co-(methyl methacrylate) containing [[(2,6-dinitrobenzyl)oxy]carbonyl] cyclohexylamine as photobase generator and a bifunctional aldehyde molecule can be achieved upon exposure to deep-UV irradiation and subsequent heating. Polymers containing the cyanoacetate functionality displayed high resist sensitivities (ca. 20 mJ/cm2) in simple contact imaging experiments. Monitoring of the resist films using UV−vis spectroscopy suggested that cross-linking of the polymers in the presence of the aldehyde moiety proceeds via a Knoevenagel reaction. Photo-cross-linking and imaging can also be achieved in the absence of the added acceptor molecule and possible mechanisms for this insolubilization are discussed. Incorporation of the reactive cyanoacetate f...

Erionite-like silicoaluminophosphate molecular sieve SAPO-17 has been synthesized using cyclohexylamine as the organic structure directing molecule. The location of Cu(II) ions exchanged into H-SAPO-17 and the interaction of Cu(II) ions with water, ammonia, methanol, and ethylene have been investigated by electron spin resonance (ESR) and electron spin echo modulation (ESEM) techniques. Simulation parameters of the 31P ESEM spectrum suggest that the hydrated Cu(II) complex, CuII(H2O)6, is located in the erionite supercage. During dehydration some of the bare Cu(II) ions migrate into the smaller cancrinite cage. Room temperature adsorption of D2O on CuH-SAPO-17 after dehydration at 723 K and subsequent O2 treatment and evacuation at the same temperature (activation) forms a Cu−aquo complex with axially symmetric ESR parameters (g|| = 2.391 and A|| = 0.0142 cm-1). This complex is suggested to be CuII(D2O)3 based on 2D ESEM data. Adsorption of ND3 on activated CuH-SAPO-17 produces CuII(ND3)3 with axially sym...

(i-PrO)2P(O)COSEt (1) reacted with NH2OH in pyridine at room temperature to give mainly (i-PrO)2P(O)NH2 (4). The formation of 4 was interpreted in terms of a spontaneous Lossen rearrangement of (i-PrO)2P(O)CONHOH (2a) formed in the reaction. A transient 31P NMR signal appearing in the reaction mixture at δ −1.8 was assigned to 2a. Trapping of (i-PrO)2P(O)NCO (5), formed in the reaction of 1 and NH2OH, by cyclohexylamine gave (i-PrO)2P(O)NHCONHC6H11 (6). Attempted isolation of 6 gave the hydrolyzed product N-cyclohexylurea (7). The reaction of 1 with NH2OMe proceeded slower than that with NH2OH and gave the expected (i-PrO)2P(O)CONHOMe (2b), which was isolated and identified. 2b converts slowly to 4 in pyridine at room temperature. In contrast, MeNHOH reacted rapidly with 1 and gave the stable crystalline (i-PrO)2P(O)CON(Me)OH (2c). The structure of hydroxamates 2 were assigned on the basis of 1H, 13C, and 31P NMR spectral data. This facile Lossen rearrangement is discussed in terms of the unusually high m...

The relative binding constants (Kb) for the coordination of amines to the palladium fragment Pd[P(o-tol)3](p-C6H4Me)Cl were determined by 1H NMR spectroscopy and decrease in the order hexylamine > benzylamine ≈ cyclohexylamine ≈ piperidine > dibutylamine ≈ diethylamine ≈ N-benzylmethylamine > morpholine > diisobutylamine > dibenzylamine ≈ tert-octylamine >> diisopropylamine > N-methylaniline. The palladium halide dimers {Pd[P(o-tol)3](p-C6H4Me)(μ-X)}2 (X = Cl (1), Br (2), I (3)) react reversibly with dibenzylamine to generate the corresponding 1:1 palladium amine adducts Pd[P(o-tol)3](p-C6H4Me)(HNBn2)X (X = Cl (12), K = 6 ± 1 × 103 M-1; X = Br (18), K= 3.5 ± 0.5 × 103 M-1; X = I (22), K = 90 ± 20 M-1), respectively. The related reaction of dibenzylamine with the iodide dimer {Pd[P(o-tol)3](p-C6H4OMe)(μ-I)}2 (21) to form Pd[P(o-tol)3](p-C6H4OMe)(HNBn2)I (24) provided the thermodynamic parameters ΔG298 K = −3.1 ± 0.1 kcal mol-1, ΔH298 K = −11.9 ± 0.1 kcal mol-1, and ΔS298 K = −30 ± 4 eu. Dimers 1−3 also rea...