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We report a highly atom-efficient integrated cofactor/co-product recycling cascade employing cycloalkylamines as multifaceted starting materials for the synthesis of nylon building blocks. Reactions using E. coli whole cells as well as purified enzymes produced excellent conversions ranging from >80 and 95 % into desired ω-amino acids, respectively with varying substrate concentrations. The applicability of this tandem biocatalytic cascade was demonstrated to produce the corresponding lactams by employing engineered biocatalysts. For instance, ϵ-caprolactam, a valuable polymer building block was synthesized with 75 % conversion from 10 mM cyclohexylamine by employing whole-cell biocatalysts. This cascade could be an alternative for bio-based production of ω-amino acids and corresponding lactam compounds.

A medicinal chemistry program to develop potent and selective LABA compounds required the synthesis of both carbon-14 and stable-isotope labelled materials. Carbon-14 labelled AZD7307 was successfully synthesised in 6 steps from [14C]chloroacetyl chloride in an overall radiochemical yield of 10%. In addition, the synthetic route of a stable labelled isotopomer of AZD7307 is also described and synthesised in four linear steps from [13C6]cyclohexylamine hydrochloride in an overall yield of 12%.

A simple and selective derivatization and detection method for o-toluidine, o-anisidine, and 2,4-dimethylaniline was developed using a sulfuric acid impregnated filter, 4-(N-chloroformylmethyl-N-methylamino)-7-nitro-2,1,3-benzoxadiazole, and a surrogate (o-ethylaniline), which allowed simple, rapid, selective, and identifiable analysis by high-performance liquid chromatography with fluorescence detection. These amines were successfully derivatized in a pH 5 buffer solution containing acetonitrile at 35°C for 10 min (linear in the range 0-400 ng/mL, n = 5, aromatic amines: r > 0.9980, aromatic amines with surrogate correction: r > 0.9997, aromatic amines in the presence of phenol and aliphatic amines with surrogate correction: r > 0.9996). The retention times of these derivatized aromatic amines were

The retention behavior of primary aliphatic amines (homologous series of aliphatic alkyl amines and cycloalkyl amines) and positional isomers of alkylamines in the hydrophilic interaction chromatography mode was studied. The study was carried out on a TSKgel Amide-80 column followed by postcolumn derivatization with fluorescence detection to describe the retention mechanism of tested compounds. The effect of chromatographic conditions including column temperature, acetonitrile content in the mobile phase, mobile phase pH (ranging from 3.5 to 6.8), and salt concentration in the mobile phase was investigated. The final mobile phase consisted of acetonitrile and solution of 20 mM potassium formate pH 3.5 in ratio 80:20 v/v. The analyses were carried out at mobile phase flow rate of 1.0 mL/min and the column temperature of 20°C. The developed method was fully validated in terms of linearity, sensitivity (limit of detection and limit of quantification), accuracy, and precision according to International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use guidelines. The proposed new methods were proved to be highly sensitive, simple, and rapid, and were successfully applied to the determinations of isopropylamine, cyclohexylamine, and cyclopropylamine in relevant active pharmaceutical ingredients.

The nitrogen atom in cyclic hetero-oligophosphane cyclo-P4Mes4C(NCy) (1) can be protonated with HCl or HBF4. The resulting cation was isolated as the BF4-, AlCl4- and GaCl4- salts and characterised by NMR spectroscopy, mass spectrometry and X-ray crystallography. According to quantum mechanical calculations, the basicity of compound 1 is comparable to that of methyl-substituted monophospha(III)guanidine. The pKα value of 1 was also determined experimentally with indicator bases.

BACKGROUND In experiments with Formosan Subterranean Termites (Coptotermes formosanus Shirakii), myo-inositol-2-monophosphate as the di-cyclohexylammonium salt was tested among other sugar derivatives, and was found to be toxic to C. formosanus when added to a moistened filter paper food source in plastic petri dishes. RESULTS Curiously, over a 9 day period, the moniliform (beaded) antennae of C. formosanus deteriorated in a stepwise fashion with the most distal pseudosegment (bead) turning brown and falling off, followed by the penultimate pseudosegment, sequentially until 7–9 days when only a stub of the antennae remained. Termites became increasingly moribund with the loss of antennae, and quit normal behavior including consuming cellulose food, and died. sn-L-glycerol-3-phosphate as the di-cyclohexylammonium salt also gave the same results. Dicyclohexylammonium hydrogenphosphate and monocyclohexylammonium dihydrogenphosphate were synthesized, to find a low cost form for application to baits, both of which also showed similar toxicity. In a trial with Fibonacci series dilutions of neat cyclohexylamine, the antennae-effecting activity became apparent in the LD30 (14 days) to LD70 range of concentrations. At the higher concentrations, darkening of the most distal parts of leg extremities were noticed. CONCLUSION Cyclohexylamine appears to be a novel termiticide with a previously unreported mechanism of toxicity. It's hydrogen phosphate salts retain the toxic effect and are inexpensive and easily synthesized.

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

A synthetic ureido mixture prepared from the reaction of 4,4′-diphenylmethane disocynanate (MDI) and cyclohexylamine without using any harmful organic solvents, has been used as a nucleating agent (PNA) for polyamide 6 (PA6). The effect of PNA on the crystallization and mechanical properties of PA6 has been studied by means of differential scanning calorimetry (DSC), polarized optical microscopy (POM), tensile test, melt flow index (MFI), and X-ray diffraction (XRD). The results show that PNA is an effective nucleation agent for PA6. PNA affects the nucleation mechanism of PA6, and substantially accelerates the crystallization rate of PA6 and gives rise to smaller crystal size. In comparison with PA6, the crystallization temperature (Tc) of PA6/PNA (100/0.5) increases 21.3°C and the degree of sub-cooling (ΔTc) decreases 23.7°C. Furthermore, because of the heterogeneous nucleation induced by PNA, the spherulites of PA6 become even and tiny based on POM observation. Polymorph transform has been obtained from XRD analysis. The virgin PA6 is free of γ-phase crystals, presented as α-phase crystals in this study, but γ-phase crystal appears after the introduction of PNA. The mechanical and thermal properties of PA6 are obviously improved by the addition of PNA. POLYM. ENG. SCI., 55:2011–2017, 2015. © 2015 Society of Plastics Engineers

Background Amines, some of which are known to cause asthma, are frequently present in the work environment, but are rarely identified as being responsible for occupational rhinitis (OR) or asthma (OA). However, amine-induced OR/OA may be underreported. To discuss this hypothesis, we report a series of patients with positive amine-specific nasal provocation test (NPT). Methods Review of the medical charts of 37 patients with OR (alone or associated with asthma), submitted to a NPT with an aliphatic or alicyclic amine (except for EDTA) present in a product used at work. Results Most patients worked in the healthcare sector or for a cleaning company. Amines were mostly present in cleaning products. Seven patients had a positive NPT. NPTs were positive for the following amines: bis(aminopropyl)laurylamine, C12-C18 alkyldimethylamine oxides, bis(2-hydroxyethyl)tallowamine oxides, 3-dimethylaminopropylamine, 2,2′-dimethyl-4,4′-methylene-bis(cyclohexylamine), lauryldimethylamine oxide. NPTs were negative for the following amines: monoethanolamine, diethanolamine, triethanolamine, isopropanolamine, triethylamine, triethylenetetramine, aminopropyltriethoxysilane, alkylpropylenediamineguanidine acetate. Conclusions The frequency of amine-induced OR/OA may be underestimated, particularly when cleaning products are incriminated. Comprehensive investigation of all cases is mandatory to ensure an efficient prevention policy and consequently a good clinical and socio-occupational prognosis of occupational respiratory disease. Am. J. Ind. Med. 57:1303–1310, 2014. © 2014 Wiley Periodicals, Inc.

The metallo-organocatalyzed enantioselective synthesis of various five-membered carbo- and heterocyclic structures through the merger of aminocatalysis with the catalytic indium(III) or copper(I) activation of α-disubstituted formyl alkynes is described. The use of indium trichloride associated with the (R)-1,1′-bis-(2-naphthylamine) ligand led to encouraging results with up to 85:15 enantiomeric ratio. After a careful examination of several other strategies, the best synergic catalytic system, which combines a chiral copper(I) complex with cyclohexylamine, afforded the enantioselective preparations of cyclopentane, indane, and pyrrolidine scaffolds with moderate to excellent control of the all-carbon quaternary stereogenic centers created through such cyclization processes.

The calcined Mg-Al layered double hydroxides (LDHs) with a Mg/Al molar ratio of 3:1 were synthesized and characterized thoroughly by X-ray diffraction (XRD), temperature-programmed desorption (TPD) of CO2, and thermogravimetric analysis (TGA). Thus the calcined Mg-Al LDHs were used as catalyst for the catalytic synthesis of disubstituted ureas from amines and CO2. The effects of reaction time, reaction temperature, pressure, solvent and calcined temperature on activity have been investigated. The results indicated that aliphatic amines, cyclohexylamine and benzylamine can be converted to the corresponding ureas selectively over the calcined Mg-Al LDHs catalysts with N-methyl-2-pyrrolidone (NMP) as solvent without using any dehydrating regent. The catalyst can be recycled several times with only slight loss of activity.

Macrocyclic and polymeric imines 5,5' and 6,6' are obtained in excellent yields by template-free polycondensation of 1,6-bis(4-formylbenzoyloxy)hexane (1) with commercially available 4,4'-methylene-bis(cyclohexylamine) (2) and with bis(2-amino-2-methylprop-1-yl)adipate dihydrochloride (4), respectively. The degree of macrocyclization during imine synthesis strongly depends on the diamine. Matrix-assisted laser desorption-ionization time-of-flight (MALDI-TOF) mass spectrometry analysis and gel permeation chromatography (GPC) measurements show that (2) leads to more macrocyclic adducts than (4). The subsequent meta-chloroperoxybenzoic acid oxidation of polyimines 5,5' and 6,6' ($ \bar M_{\rm n} $ = 1650-11 200 g mol(-1) , $ \bar M_{\rm w} $ = 3800-27 350 g mol(-1) ) yields the corresponding polyoxaziridines 7,7' and 8,8' consisting of macrocyclic and linear polymeric structures ($ \bar M_{\rm n} $ = 1750-8050 g mol(-1) , $ \bar M_{\rm w} $ = 3250-15 800 g mol(-1) ). The synthesized polyoxaziridines are relatively stable and storable at room temperature.

Colorless block-shaped crystals of the title compound are prepared from aqueous solutions of Mn(NO3)2, NaN3, and cyclohexylamine hydrochloride (room temperature, 2 d, 50% yield).

The Ti-catalyzed iminoamination reaction of alkynes, aniline or cyclohexylamine, and tert-butyl isocyanide produces 1,3-diimines, which are directly coupled with glycine ethyl ester hydrochloride to give 2-carboxypyrrole derivatives.

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

Catalytic hydrodechlorination reactions of p-chloro-m-cresol (PCMC) and p-chloroaniline (PCA) were investigated in a slurry reactor using a Ru/TiO2 catalyst. The organic reaction intermediates, m-cresol and aniline, were further converted into methylcyclohexanol and cyclohexylamine respectively. Kinetics of PCMC hydrogenation was studied over the ranges in temperature, 323–373 K, H2 partial pressure, 0.34–1.38 MPa, PCMC concentration, 3.5–14 mM and catalyst loading, 0.1–2 kg/m3. The reaction orders with respect to PCMC and H2 were evaluated as 0.5 and 0.8 respectively. It was found that aniline hydrogenation is the rate-determining step in the hydrotreatment of PCA. Kinetics of aniline hydrogenation was studied at 343 and 363 K over the ranges in H2 partial pressure, 0.34–1.38 MPa, aniline concentration, 5.4–21.5 mM and catalyst loading, 0.1–0.6 kg/m3. The reaction orders with respect to aniline and H2 were found to be 1.3 and 1.0 respectively. © 2012 Canadian Society for Chemical Engineering

The Kabachnik–Fields reaction of benzaldehyde, cyclohexylamine, and dimethyl phosphite carried out at 80°C in acetonitrile takes place via an imine (PhCNcHex) intermediate, as the monitoring by in situ Fourier transform IR spectroscopy suggested. The corresponding α-hydroxyphosphonate was also formed in a quantity of 13% that was not converted to α-aminophosphonate under the conditions applied. The outcome was similar to the Kabachnik–Fields reaction with diethyl phosphite as the P-component. Molecular modeling and subsequent DFT calculations carried out under solventless conditions supported the experimental results and indicated the formation of a high number of ideally positioned H bonds as the key determinant for the conformation of the starting, intermediate, and product states. The relative energies of the possible intermediates were in accord with the observation that the formation of the α-hydroxyphosphonate is a “dead-end” route. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 23:171–178, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.20767

Treatment of N-2-(1,1-dichloroalkylidene) cyclohexylamines with excess sodium methylate in methanol under reflux afforded N-2-(1,1-dimethoxyalkylidene)-cyclohexylamines, which were hydrolysed to the corresponding 1,1-dimethoxy-2-alkanones. N-1-(2,2-dichloro-1-phenylpropylidene) cyclohexylamine on the other hand yielded dehydrochlorination and nucleophilic substitution.

Piperidine, cyclohexylamine, methoxide ion and para‐thiocresolate ion react with 2‐chloro‐3‐nitroquinoxaline 1 by selectively substituting the nitro group, in contrast to the behavior of most ortho‐chloronitroaromatics which loose halide when subjected to nucleophilic substitution reactions. This inversion is interpreted as being due to the lack of activation of the 2‐position by the nitro group in the 3‐position because of the low value of the π‐bond index between these two vertices. It is also suggested that the substitution by neutral reagents such as amines is strongly influenced by stabilizing interactions between the negatively charged nitro group and the ammonium moiety in the σ complex; this built‐in solvation may be responsible for inversions in the chemoselectivity between chloro and nitro nucleofugicities. Copyright © 1988 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim

A bridged silsesquioxane was obtained from a precursor synthesized by the reaction of glycidoxypropyl(trimethoxysilane) (2 mol) with cyclohexylamine (1 mol). The polycondensation in the presence of formic acid produced a hybrid material exhibiting a short-range order based on elongated organic channels accommodating the pendant cyclohexyl fragments, bounded by inorganic domains. The presence of functional groups in the organic channels (tertiary amine, ether, hydroxyl), can be used to retain small organic molecules capable of forming hydrogen bonds. Aspirin was used as a probe to illustrate this possibility.

The interfering effects of various substances on the Winkler reaction as applied to dissolved oxygen microanalysis have been elucidated. Ammonia, cyclohexylamine and morpholine do not interfere at concentrations encountered in power-station practice. Interference from sulphite ion is overcome by the reversed-reagents procedure introduced by Schwartz & Gurney, but this is invalidated in the presence of ferrous ion or hydrazine. Interference from this source is fully overcome by pre-treatment of the water sample with an equilibrated strongly acidic cation-exchange resin.

Of many compounds examined in vapour form in moisture-laden air, a number will, in varying degrees, confer protection upon ferrous and some non-ferrous metals when contained in the same enclosed space. Certain esters (e.g. n- and iso-propyl benzoates, n-butyl benzoates and methyl cinnamate) afford good protection to steel. Complete inhibition of the corrosion of steel and cast iron may be effected in moist air, even when heavily contaminated with sulphur dioxide, by certain amine carbonates, e.g. cyclohexylamine carbonate. These compounds also possess, in marked degree, the property of arresting the further corrosion of iron and steel surfaces that have already become rusted by exposure to moist polluted air.

It has been shown that in the preparation of N-cyclohexylbenzothiazole-2-sulphenamide by the reaction of 2-mercaptobenzothiazole with cyclohexylamine in the presence of sodium hypochlorite, N-cyclohexyl-benzothiazole-2-sulphonamide, sodium benzothiazole-2-sulphonate, benzothiazole-2-sulphonyl chloride, 2,2′-dithiobisbenzothiazole, and probably sodium benzothiazole-2-sulphinate can be formed as by-products, in amounts depending on pH, temperature and amount of amine used. Mechanisms are suggested for the reactions involved.

Epoxy–clay nanocomposites were synthesized using different types of modified montmorillonite, either with a classic quaternary ammonium salt or with protonated adducts synthesized by reacting resorcinol diglycidyl ether with monoamines (benzylamine or cyclohexylamine). The chemical structure was investigated using Fourier transform infrared and 1H NMR spectrometry. The nanocomposite structures were confirmed using X-ray diffraction analysis and transmission electron microscopy. The influence of the montmorillonite modifier on the glass transition temperature of the cured composites was studied using dynamic mechanical analysis. Copyright © 2007 Society of Chemical Industry

Particulate samples collected from a laboratory ventilation manifold during routine maintenance were analyzed to determine if particulate composition had changed as a result of changes in the laboratory's atmosphere. This ventilation manifold exhausts more than 100 fume hoods. The particulate samples were analyzed using static secondary ion mass spectrometry (SIMS). The negative SIMS spectra showed abundant Cl-, NO3-, and HSO4-, consistent with the use of mineral acids in the laboratory. Cluster anions containing primarily Zn (but also other transition metals) were detected, which signaled corrosion of the manifold's galvanized steel by the volatilized acids. The most abundant ions in the cation SIMS spectra were derived from cyclohexylamine (CHA), which had been used as an antiscaling agent in the facility's boiler. Steam from the boiler, which contained CHA, was used to humidify the building air; this practice stopped in 1997. The abundances of the CHA-derived ions were significantly lower in the samples collected in 2004 and 2006 than in the 1992 samples, indicating that the CHA is being slowly depleted. Changes in the relative abundances suggest exponential depletion from the manifold with rate constants that are on the order of 0.01 to 0.04 month-1.

A series of fully aliphatic polyimidosiloxanes (APISiO) were prepared by poly(addition/condensation) reaction of bicyclo (2,2,2) oct-7-ene-2,3,5,6-tetracarboxylic dianhydride or cyclobutane-1,2,3,4-tetracarboxylic dianhydride and varying composi- tions of 1,3-bis (3-amino propyl)-tetra methyl disiloxane and rigid adamantyl di- amines (1,3-diaminoadamantane or 3,3 0 -diamino-1,1 0 -diadamantane) or flexible alicy- clic diamines (4,4 0 -methylene bis(cyclohexylamine) or 4,4 0 -methylene bis(2-methylcy- clohexylamine)). High temperature one-step synthesis in m-cresol was employed to obtain APISiOs with intrinsic viscosity in the range of 0.28-0.59 dL/g. The final materials were characterized by 1 H and 13 C NMR, 29 Si-MAS-NMR and IR spectro- scopic analysis, thermogravimetric and differential scanning calorimetric analysis, and wide angle X-ray diffractometry. UV-visible spectra revealed the optical behavior of the polyimides. It was found that the APISiOs containing appropriate ratio of ada- mantyl moieties together with flexible aliphatic siloxane groups exhibit good thermal and mechanical stabilities, solubility, fair transparency, and low dielectric constant (2.4-2.7). V C 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5254-5270, 2006

Using phosphorus pentachloride as a substrate, carbacylamidophosphates of the general formula (p-X-C6H4) C(O)NHP(O)(R)2; (X=Cl and R=Cl, 2a; X=Br and R=Cl, 3a; X=Me and R=Cl, 4a; X=Cl and R=piperidine, 2b; X=Br and R=piperidine, 3b; X=Me and R=piperidine, 4b; X=H and R=cyclohexylamine, 1c; X=Cl and R=cyclohexylamine, 2c; X=Br and R=cyclohexylamine, 3c; X=Me and R=cyclohexylamine, 4c; X=H and R=p-Me-cyclohexylamine, was prepared and characterized by 1H, 31P and 13C NMR and IR spectroscopy and elemental analysis. Different group attached on phosphorus nuclei affect on IR and NMR spectra. Three-bond coupling constants between phosphorus and carbon nucleus, 3J(P,Caliphatic) in the 1b–4b and 1c–4c containing piperidine or cyclohexylamine groups, were greather than two-bond coupling constants, 2J(P,Caliphatic). The structures of 2b and 3b were determined by single-crystal X-ray diffraction techniques. The both molecule crystals are composed of a centrosymmetric dimer via N-H···O bonds. 3b exists as two independent molecules in crystal lattice.

In order to determine whether hydrogen peroxide (H2O2) generated by polyamine oxidative degradation is involved in the development of lateral roots in soybean, the length and the number of lateral roots, the activities of polyamine oxidases and diamine oxidases, and the endogenous free polyamine and H2O2 content were analyzed in soybean (Glycine max (Linn.) Merr.) main roots of 2-d-old seedlings after treatments for 2 d with exogenous β-hydroxyethylhydrazine (an inhibitor of polyamine oxidases), H2O2, putrescine, cyclohexylamine (an inhibitor of spermidine synthase) or N, N′-dimethylthiourea (a scavenger of hydrogen peroxide). β-hydroxyethylhydrazine treatment strongly inhibited the development of lateral roots in soybean seedlings, reduced the activities of polyamine oxidases and diamine oxidases, decreased H2O2 levels, and led to the accumulation of endogenous polyamines in the main roots. The inhibitory effect of β-hydroxyethylhydrazine on root development could be alleviated by exogenously applied 10 μmol/L H2O2 (a major product of polyamine oxidation). Treatment with cyclohexylamine and putrescine promoted root growth slightly, but treatment with cyclohexylamine plus N, N′-dimethylthiourea or putrescine plus N, N′-dimethylthiourea prevented the development of soybean lateral roots. The effects of these treatments on the development of soybean lateral roots were consistent with the changes in endogenous H2O2 levels. These results suggest that the development of soybean lateral roots is associated with the oxidative degradation of polyamines, and that their products, especially H2O2, are likely to play an important role in the growth of soybean lateral roots. (Managing editor: Ping He)

In order to assess the effectiveness of applying penetrating corrosion inhibitors to the surface of reinforced concrete, it is necessary to devise accurate methods for their detection and quantification. In this paper, methods for ion chromatographic analysis of a variety of amines, alkanolamines, and associated anions, which may be used as corrosion inhibitors for steel reinforcement in concrete, are described. By careful adjustment of the conditions for analysis, these inhibitors were readily identified and quantified in concrete/cement pore solutions or digests. Characterisation of the cationic inhibitors, ethanolamine, quaternary methylammonium, dimethylethanolamine, cyclohexylamine, guanidine, and arginine, and the anionic inhibitors, nitrite, molybdate, acetate, benzoate, and azelate, was carried out conductimetrically. To enhance the sensitivity of detection, amperometry was used for the analysis of triethanolamine and low concentrations of ethanolamine. Ion chromatography was also used as a means of obtaining a distribution profile of the concentrations of inhibitor ions present throughout a concrete structure.

Fluoroalkyl end-capped N-acryloxysuccinimide (ASuI) cooligomers were prepared under very mild conditions by the cooligomerizations of fluoroalkanoyl peroxides with ASuI and comonomers such as N,N-dimethylacrylamide (DMAA) and acryloylmorpholine (ACMO). These fluorinated ASuI cooligomers thus obtained were in general easily soluble in water and common organic solvents. These fluorinated ASuI cooligomers were also able to reduce the surface tension of water quite effectively to around 20 mN/m with a clear break point resembling a critical micelle concentration (CMC), although the corresponding nonfluorinated ASuI cooligomers were not effective for reducing the surface tension of water. Fluorinated ASuI cooligomers were applicable to new fluorinated precooligomers, and these precooligomers could react with several amino compounds such as aniline, cytosine, and cyclohexylamine to afford fluorinated cooligomer-bound aromatic and cyclohexyl segments under mild conditions. Of particular interest, these fluorinated precooligomers were able to react with low molecular weight biocides such as sulfathiazole (STZ) and 3-amino-5-hydroxypyrazole (AHP) to give the corresponding fluorinated cooligomers containing antibacterial segments under similar conditions. These cooligomers were shown to have not only a good oleophobicity imparted by fluorine but also surface antibacterial activity against Staphylococcus aureus. Therefore, our present fluorinated cooligomers containing antibacterial segments are suggested to have high potential for new fluorinated functional materials through their surface active property and surface antibacterial activity. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3874–3880, 2004

The effects of the addition of different salts (quaternary bromides or NaBr) on the viscosity (measured under Newtonian flow conditions) of sodium dodecylbenzenesulfonate (SDBS) micellar solutions were studied at 30°C. Tetra-n-butylammonium bromide (Bu4NBr) was found most effective in increasing the viscosity (due to possible change in micellar shape) at fairly low SDBS concentration (50 mM). The effectiveness of Bu4NBr may be due to the presence of four butyl chains and to the positive charge on its counterion (Bu4N+) which can subsequently interact with anionic SDBS micelles electrostatically as well as hydrophobically; owing to solubility/steric problems, other salts were ineffective. Organic additives such as cyclohexylamine and cyclohexanol had marginal effects on viscosity when added to 50 mM SDBS solutions having no Bu4NBr. However, in the presence of Bu4NBr, the effect was dependent on salt concentration and the nature of the additive. The overall effect is discussed on the basis of change in the solubilization site of the additive in the presence of Bu4NBr.

Two new polyamidoamines derived from piperazine (Pip)/cyclohexylamine (CHA) and N,N′-methylene bisacrylamide (MBA) were synthesized and subsequently copolymerized with N-vinylpyrrolidone (NVP) under suitable reaction conditions to yield the respective copolymers (Pip–MBA–NVP and CHA–MBA–NVP). The synthesized materials were characterized by spectroscopic techniques. The material surface characteristics were checked by contact angle measurement, and the data established the relative hydrophilic characteristics of the synthesized copolymers with respect to the control poly(N-vinylpyrrolidone). A thrombus-formation study indicated less (

The antioxidative and radical scavenging activity of the 3,4-dihydroxymandelic acid (DHMA) amides of hexylamine, 2-ethylhexylamine, octylamine, and cyclohexylamine was determined by several physicochemical test systems. The amides were synthesized by protecting group-free coupling of in situ prepared N-hydroxysuccinimidylester of DHMA and the amines. The radical scavenging activity was determined using the DPPH (2,2-diphenyl-1-picrylhydrazyl) method and by quenching superoxide anions generated using a horse radish peroxidase/H 2 O 2 system. In the DPPH assay, all amides show higher radical scavenging activity (EC 50 0.09-0.12 mol/mol DPPH ) compared to the standard antioxidants ascorbic acid (EC 50 0.27 mol/mol DPPH ) and tocopherol (EC 50 0.25 mol/mol DPPH ). The amides are also more potent superoxide radical scavengers (IC 50 0.9, tocopherol 0.08). The DHMA octylamide in combination with ascorbic acid shows a synergistic antioxidative effect in the emulsion model. In conclusion, the new alkylamides of DHMA are easy to synthesize, potent radical scavengers and protect lipids, in particular the highly unsaturated, both in bulk and in emulsions against autoxidation.

The morphology and the melting behavior of poly(-caprolactone)/epoxy blends (PCL/epoxy) have been investigated by SEM and DSC. The mechanism of phase separation varies with the curing temperature and PCL con- tent, which can be deduced from the cured morphology of the blend. Higher temperature leads to lower blend viscosity and a higher curing rate, and the final morphology is deter- mined by the competition of these two factors. The PCL melting behavior of the blend is influenced by the extent of phase separation and crystallization during curing. The dual melting behavior of the PCL blend can be ascribed to the interference of the epoxy, which results in the formation of less perfect PCL crystallites melted at lower temperature. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3107-3114, 2003

The carbocyclization of a wide range of formylalkynes is achieved by using Fe(acac)3 and cyclohexylamine as synergistic catalytic system.

The use of disulfonylamines as counter-ions allows the synthesis of stable ionic gold(I) complexes with the amine ligands cyclohexylamine, benzylamine, 3-iodobenzylamine, morpholine, pyrrolidine, and piperidine. There is a considerable increase in stability for the morpholine complex compared to the previously synthesised chloro derivative; the benzylamine derivatives displayed better solubility and crystallinity than their chloro analogues. The use of silver disulfonylamine derivatives in the syntheses led in two cases to the incorporation of silver into the products, with concomitantly poor yields. Crystal structure determinations of eight complexes revealed, as expected, extensive systems of N−H···O hydrogen bonds. Amines with NH functions tend to form hydrogen-bonded chain motifs, those with NH2 as donor group form layers of linked ring patterns. It thus seems that the packing can more easily be classified in terms of influence of the cation than of the anion. Some C−H···O hydrogen bonds were also observed, but play a less important role. Aurophilic contacts were not observed, although one mixed gold/silver complex displayed short Au···Ag contacts. Of the two compounds containing iodine, only one showed short I···I contacts.

Over the last 50 years methacrylic polymers, especially poly(methyl methacrylate) (PMMA), have reached a noteworthy place in world polymer production. However, for special applications that require thermal properties, polycarbonates take the place of PMMA because of the latter's low glass transition temperature (T g ) of 105°C. The aminolysis reaction of PMMA with cyclohexylamine in xylene was studied to obtain a polyglutarimide exhibiting higher T g values. The mechanism involving aminolysis and further amidization of ester groups was correlated with the experimental characterization of all the species created during the reaction. Poly(N-cyclohexylacrylamide) and polyglutarimide (prepared from this precursor) were prepared in order to determine the special characteristics of these model compounds by FTIR. This method abled the quantification of ester, amide, acid, and imide groups. This aminolysis reaction was optimized (190-250°C; ratio of constituents, 0.5: 3) by spectroscopically following the different groups and monitoring the increase of the T g . Poly(N-cyclohexyl glutarimide) (65%) containing amide groups (25%) and acid groups (10%) presents a T g value of 195°C.

This effort determined if enhancements to the properties of fully cured EPON 830-4,4′-Methylene Bis Cyclohexylamine epoxy resin systems (ERSs) could be induced by thermally curing them, while also simultaneously exposing them to economically generated magnetic fields (MFs). Stoichiometric mixes were cured for 5 hours at 121°C while being exposed to MFs between 0.1290 and 0.8810 Tesla. Exposed and control specimens were simultaneously cast from the same mix in each run. The resulting specimens were mechanically and thermally tested to find any property differences. This effort determined that under these conditions there were no modifications to the properties of MF exposed, fully thermally cured, ERSs relative to their controls.

Aliphatic polyimides containing adamantyl units (APIs) were prepared by the poly(addition/condensation) of a dianhydride bicyclo[2.2.2]octane-2,3,5,6-tetracarboxylic 2,3 : 5,6-dianhydride with a rigid diamine, 1,3-diaminoadamantane or 3,3′-diamino-1,1′-biadamantyl, and a flexible diamine, 4,4′-methylenebis(cyclohexylamine) or 1,4-cyclohexanediamine. One-step polymerizations were conducted at 80–200°C in m-cresol, producing APIs with inherent viscosities up to 0.53 dL g−1. These APIs are soluble in haloalkanes, m-cresol, and sulfuric acid and show high thermal stability and excellent transparency. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 3584–3590, 1999

The oxidative addition of the bidentate Schiff base 1,4-(CyNCH)2-2,5-Cl2C6H2 to tris(dibenzylideneacetone) dipalladium(0) gave the dicyclopalladated complex [(Cl)PdN(Cy)C(H)C6H2C(H)N(Cy)Pd(Cl)]n (1). Treatment of 1 with LiBr gave the analogous bromo derivative [(Br)PdN(Cy)C(H)C6H2C(H)N(Cy)Pd(Br)]n (2). Reaction of 1 or of 2 with tertiary phosphines in 1:2 or 1:4 molar ratios gave the dinuclear cyclometallated [(L)(X)PdN(Cy)C(H)C6H2C(H)N(Cy)Pd(X)(L)] (3–9), and non-cyclometallated complexes [(L)2(X)PdN(Cy)C(H)C6H2C(H)N(Cy)Pd(X)(L)2] (10–14) (X = Cl, Br; L = PPh3, PEtPh2, PEt2Ph, PMePh2, as appropriate), respectively, Treatment of 1 or of 2 with thallium acetylacetonate gave the dinuclear cyclometallated complex [(MeCOCHCOMe)PdN(Cy)C(H)C6H2C(H)N(Cy)Pd(MeCOCHCOMe)] (15). Neue Dinukleare Cyclometallierte Komplexe von Palladium(II) durch oxidative Addition mit N,N-(2,5-dichloro)terephthalylidenbis(cyclohexylamin) Die oxidative Addition der zweizahnigen Schiff-Base 1,4-(CyNCH)2-2,5-CI2C6H2 an Tris(dibenzylidenaceton)dipalladium(0) ergab den dicyclopalladierten Komplex [(Cl)PdN(Cy)C(H)C6H2C(H)N(Cy)Pd(Cl)]n (1). Die Umsetzung von 1 mit LiBr ergab das analoge Bromoderivat [(Br)PdN(Cy)C(H)C6H2C(H)N(Cy)Pd(Br)]n (2). Reaktionen von 1 oder 2 mit tertiaren Phosphinen in den Molverhaltnissen 1:2 bzw. 1:4 fuhrten zu den entsprechen den dinuklearen, cyclometallierten Komplexen [(L)(X)PdN(Cy)C(H)C6H2C(H)N(Cy)Pd(X)(L)] (3–9) und den nicht-cyclometallierten Komplexen [(L)2(X)PdN(Cy)C(H)C6H2C(H)N(Cy)Pd(X)(L)2] (10–14) (X = Cl, Br; L = PPh3, PEtPh2, PEt2Ph, PMePh2). Die Behandlung von 1 bzw. 2 mit Thalliumacetylacetonat fuhrte zu dem dinuklearen, cyclometallierten Komplex [(MeCOCHCOMe)PdN(Cy)C(H)C6H2C(H)N(Cy)Pd(MeCOCHCOMe)] (15).

In this study, surface modification of lignosulfonates (LSs) was investigated for potential reinforcement of styrene–butadiene rubber compounds. Lignins are naturally occurring amorphous, highly branched polymers consisting of aromatic and aliphatic segments with polar functional groups such as hydroxyl, methoxy, carbonyl, and carboxyl. The polarity and hydrophilic nature render lignin incompatible with nonpolar rubber materials. In this study, cyclohexylamine (CA) modification of LS was evaluated for enhancement of compatibility with rubber via proton transfer and hydrogen bonding interactions. X-ray photoelectron spectroscopy data confirm attachment of CA onto the surface of LS. The cure and scorch times of rubber compounds were shortened, and the crosslink density enhanced with an increase of the amount of CA in modified LS. The tensile strength at break increased by almost 45%; the 100% modulus and elongation at break also showed significant improvements. The values of storage modulus and loss tangent increased by 13% and 18%, respectively. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40123.

The calcined Mg-Al layered double hydroxides (LDHs) with a Mg/Al molar ratio of 3:1 were synthesized and characterized thoroughly by X-ray diffraction (XRD), temperature-programmed desorption (TPD) of CO2, and thermogravimetric analysis (TGA). Thus the calcined Mg-Al LDHs were used as catalyst for the catalytic synthesis of disubstituted ureas from amines and CO2. The effects of reaction time, reaction temperature, pressure, solvent and calcined temperature on activity have been investigated. The results indicated that aliphatic amines, cyclohexylamine and benzylamine can be converted to the corresponding ureas selectively over the calcined Mg-Al LDHs catalysts with N-methyl-2-pyrrolidone (NMP) as solvent without using any dehydrating regent. The catalyst can be recycled several times with only slight loss of activity.

Polyisoprene was vulcanized with N-cyclohexylbenzothiazole sulfenamide (CBS), sulfur, and zinc oxide by heating in a Differential Scanning Calorimeter (DSC) at a programmed rate to given temperatures. The reaction was quenched and the product analyzed. Soluble curatives and reaction intermediates were analyzed by high-performance liquid chomatography (HPLC) and the crosslink density of the network determined by swelling. The delayed action of the CBS accelerator is explained in terms of an exchange reaction between benzothiazole terminated polysulfidic pendent groups on the polymer chain and CBS to yield unreactive amine terminated pendent groups and 2-bisbenzothiazole-2,2′-disulfide (MBTS). MBTS reacts with sulfur to form 2-bisbenzothiazole-2,2′-polysulfides (MBTPs), which also form pendent groups. Crosslinking does not commence until all of the CBS has been consumed and pendent groups are no longer deactivated. 2-Mercaptobenzothiazole (MBT) is released only on crosslinking. When MBT is present in the formulation at the outset of the reaction it traps cyclohexylamine released when CBS adds to the chain as a pendent group. The MBT-amine salt participates in a reaction that regenerates MBTS, which is, thus, not consumed in the vulcanization process. ZnO does not react with CBS, and its role in increasing the crosslink density is attributed to its promoting crosslinking reactions between pendent groups and neighboring chains rather than intramolecular reactions, which lead to cyclization. © 1996 John Wiley & Sons, Inc.

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

The N-isocyanodialkylamine metal complexes [M(CO)5CN-NR2] (M = Cr, W), trans-[MI2(CNNR2)2] (M = Pd, Pt), trans-[Pt(Cl)(CNNR2)(PPh3)2]BF4, and cis-[PtCl2(CNNR2)(PPh3)] [R = Et, iPr; 2 R = -{CHMe(CH2)3CHMe}-] react with primary amines to give the amino(hydrazino)carbene metal complexes [M(CO)5(C(NHR′)NHNR2}] (R′ = Me, nPr, Cy) (1–9), trans-[PtI2{C(NHMe)NHNR2}2] (10–12) and trans , and the amine adducts cis-[PtCl2{C(NHMe)NHNC(H)(Me) (CH2)3CHMe}(PPh3)] H2NMe (14), and trans-[PdI2{C (NHMe)NHNC(H)(Me)(CH2)3CHMe}2] 2 H2NMe (15). With secondary amines the amino(hydrazino)carbene metal complexes trans (18) and trans-[PtCl{C(NEt2)NHNEt2} (PPh3)2]BF4 (19) Were isolated. The complexes trans-[PtI2{C(NHCy)NHNiPr2}CNNiPr 2] (20) and trans-[PdI2 (NH2Cy){C(NHCy)NHNiPr2}] (21) were obtained by reaction of trans-[MI2(CNNiPr2)2] (M = Pd, Pt) with cyclohexylamine. The structures were assigned on the basis of IR, NMR- (1H, 13C, 31P), and mass spectroscopy as well as an X-ray structural analysis of 21.