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A gas chromatographic headspace analysis method was used to experimentally determine gas-to-liquid partition coefficients and infinite dilution activity coefficients for two saturated (2,2,4-trimethylpentane, cyclooctane) and 3 unsaturated hydrocarbons (1,7-octadiene, 1-hexyne, 4-vinyl-1-cyclohexene), one aromatic hydrocarbon (propylbenzene), one haloalkane (1,3-dichloropropane) and four halobenzenes (fluorobenzene, chlorobenzene, 1,2-dichlorobenzene, bromobenzene), two cyclic ethers (tetrahydrofuran, 1,4-dioxane), two alcohols (1-propanol, 2-propanol), three alkyl acetates (ethyl acetate, butyl acetate, pentyl acetate), and one alkanenitrile (acetonitrile) dissolved in 2-pyrrolidone at 298.15 K. The experimental results of the headspace chromatographic measurements, combined with published solubility and infinite dilution activity coefficient data, were used to derive Abraham model correlations for describing solute transfer into 2-pyrrolidone. Mathematical correlations based on the Abraham model describe the observed partition coefficient and activity coefficient data to within 0.14 log10 units (or less).

This study describes a time-dependent self-assembly generation of new copper(II) coordination compounds from an aqueous-medium reaction mixture composed of copper(II) nitrate, H3bes biobuffer (N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid), ammonium hydroxide, and benzenecarboxylic acid, namely, 4-methoxybenzoic (Hfmba) or 4-chlorobenzoic (Hfcba) acid. Two products were isolated from each reaction, namely, 1D coordination polymers [Cu3(μ3-OH)2(μ-fmba)2(fmba)2(H2O)2]n (1) or [Cu2(μ-OH)2(μ-fcba)2]n (2) and discrete tetracopper(II) rings [Cu4(μ-Hbes)3(μ-H2bes)(μ-fmba)]·2H2O (3) or [Cu4(μ-Hbes)3(μ-H2bes)(μ-fcba)]·4H2O (4), respectively. These four compounds were obtained as microcrystalline air-stable solids and characterized by standard methods, including the single-crystal X-ray diffraction. The structures of 1 and 2 feature distinct types of metal-organic chains driven by the μ3- or μ-OH- ligands along with the μ-benzenecarboxylate linkers. The structures of 3 and 4 disclose the chairlike Cu4 rings assembled from four μ-bridging and chelating aminoalcoholate ligands along with μ-benzenecarboxylate moieties playing a core-stabilizing role. Catalytic activity of 1-4 was investigated in two model reactions, namely, (a) the mild oxidation of saturated hydrocarbons with hydrogen peroxide to form alcohols and ketones and (b) the mild carboxylation of alkanes with carbon monoxide, water, and peroxodisulfate to generate carboxylic acids. Cyclohexane and propane were used as model cyclic and gaseous alkanes, while the substrate scope also included cyclopentane, cycloheptane, and cyclooctane. Different reaction parameters were investigated, including an effect of the acid cocatalyst and various selectivity parameters. The obtained total product yields (up to 34% based on C3H8 or up to 47% based on C6H12) in the carboxylation of propane and cyclohexane are remarkable taking into account an inertness of these saturated hydrocarbons and low reaction temperatures (50-60 °C). Apart from notable catalytic activity, this study showcases a novel time-dependent synthetic strategy for the self-assembly of two different Cu(II) compounds from the same reaction mixture.

Aerobic oxidation of hydrocarbons is one of the research fronts in organic chemistry as well as in chemical engineering. In this aspect, many efforts are devoted to develop heterogeneous catalysts that can convert hydrocarbon to its corresponding alcohol/ketone (ol/one) with selectivity more than 90%. However, achieving this target becomes difficult due to possible secondary reactions of initially formed ol/one mixture. Hence, this study aims to report the catalytic activity of Fe(BTC) (BTC: 1,3,5-benzenetricarboxylate) and tetrabutylammonium bromide (TBAB) in aerobic oxidation of cyclooctane at 73% conversion to its respective ol/one with 84% selectivity after 24 h at 120 °C in the absence of any radical initiators. Interestingly, the selectivity of ol/one is higher than 90% at cyclooctane conversion around 20% under present reaction conditions. Reusability and leaching experiments demonstrate the stability of Fe(BTC) during the oxidation reaction. Furthermore, the present catalytic system can also be extended to oxidize other linear hydrocarbons to their respective ol/one products with the selectivity ranging between 88–97 %.

International audience; Using a synthetic method, the phase behavior of the CO2 (1) + cyclooctane (2) binary system was for the first time experimentally studied between 292.95 K and 373.55 K. In this temperature range, the bubble- and dew-point pressures, ranging from 13.2 to 183.4 bar were measured for carbon dioxide mole fractions between 0.1014 and 0.9701. A total of 96 experimental data points were acquired. The experimental data were obtained using a high-pressure cell by visual observation of phase transitions. These measurements made it possible to conclude that the studied binary system probably exhibits a type V phase behavior in the classification scheme of Van Konynenburg and Scott. In particular, the experimental temperature of the suspected lower critical end point (LCEP) was found to be 303 K. Despite the complexity of the phase behavior, the experimental data could be accurately correlated with the Peng-Robinson equation of state combined with sophisticated mixing rules that either involve temperature-dependent binary interaction parameters (kij(T)) or that embed the residual part of the Wilson activity coefficient model.

The conformational properties of ring compounds such as cycloalkanes determine to a large extent their stability and reactivity. Therefore, the investigation of conformational processes such as ring inversion and/or ring pseudorotation has attracted a lot of attention over the past decades. An in-depth conformational analysis of ring compounds requires mapping the relevant parts of the conformational energy surface at stationary and also at non-stationary points. However, the latter is not feasible by a description of the ring with Cartesian or internal coordinates. We provide in this work, a solution to this problem by introducing a new coordinate system based on the Cremer–Pople puckering and deformation coordinates. Furthermore, analytic first- and second-order derivatives of puckering and deformation coordinates, i.e., B-matrices and D-tensors, were developed simplifying geometry optimization and frequency calculations. The new coordinate system is applied to map the potential energy surfaces and reaction paths of cycloheptane (C7H14), cyclooctane (C8H16), and cyclo[18]carbon (C18) at the quantum chemical level and to determine for the first time all stationary points of these ring compounds in a systematic way.

A series of tBu- and iPr-substituted PNP–pincer Ir and Rh complexes with pyrrole-based core were synthesized and characterized. The structures of the obtained complexes were varied depending on the size of alkyl substituents and ligands other than PNP ligand. All of them exhibit low activity toward transfer dehydrogenation of cyclooctane., ファイル公開：2019-04-23

A series of polycyclic hydrocarbons containing cyclopropane moieties 1,2-annelated or spiro-condensed with cyclooctane ring were investigated under oxidative conditions. Four oxidizing systems (O3 on SiO2, dioxirane derived from trifluoroacetone, CrO3 and RuO4, generated in situ), were employed to evaluate and compare their reactivity and usefulness. RuO4 was found to be the best one, considering its oxidative power together with a simple preparative procedure. The conditions for specific oxidation of polycyclic hydrocarbons were found. Novel cyclooctane derivatives containing cyclopropyl carbonyl moieties were obtained.

Altering the cultivation conditions, such as temperature, media compositions, illumination, aeration, the shape of the culturing flask, etc., is regarded as a useful strategy for the exploitation of structurally novel and bioactive secondary metabolites, which inspired us to explore the chemical and pharmacological diversities from the genetically powerful fungus Alternaria brassicicola. As a result, twelve fusicoccane-type diterpenoids, including eight new ones, termed brassicicenes Q-X (1-8), were isolated from a modified rice medium. Biosynthetically, all these compounds were derived from the mevalonic acid (MVA) pathway, and their structures incorporating absolute configurations were assigned by the interpretation of spectroscopic (HRESIMS and 1D and 2D NMR) analyses, chemical conversion, a modified Mosher's method, 13C NMR calculation, and single-crystal X-ray diffraction (Cu Kα). Structurally, compound 1 was an unusual 16-nor-dicyclopenta[a,d]cyclooctane diterpenoid bearing a fused cyclopent-2-en-1-one moiety. In addition, compound 3 was found to show significant anti-inflammatory activity against the production of NO, TNF-α, and IL-1β at 10 μM. Further western blot and immunofluorescence experiments found the mechanism of action to be that 3 inhibited the NF-κB-activated pathway, highlighting it as a promising starting point for the development of new anti-inflammatory agents.

A new hybrid Fe3O4@mSiO(2)@Cu-4 material was constructed by loading a bio-inspired tetracopper(II) coordination compound [Cu-4(mu(4)-O){N(CH2CH2O)(3)}(4)(BOH)(4)][BF4](2) (Cu-4) onto the Fe3O4@mSiO(2) core-shell nanoparticles (NPs) composed of a magnetite (Fe3O4) core and mesoporous silica (mSiO(2)) shell with perpendicularly aligned channels. The obtained Fe3O4@mSiO(2)@Cu-4 magnetic nanoparticles were characterized by transmission electron microscopy (TEM), FT-IR spectroscopy, thermogravimetric analysis (TGA), powder X-ray diffraction (PXRD), and field-dependent magnetization. This hybrid material acts as a magnetically recoverable C-H functionalization nanocatalyst, namely for the mild oxidation, by t-butyl hydroperoxide at 50-70 degrees C in acetonitrile medium, of cycloalkanes (cyclopentane, cyclohexane, cycloheptane, and cyclooctane) to the corresponding alcohols and ketones (with up to similar to 15% yields based on cycloalkane; TON 335). A related oxidation process using cyclohexanol as a more reactive substrate leads to the formation of cyclohexanone in up to similar to 25% yield (TON 570). The Fe3O4@mSiO(2)@Cu-4 nanocatalyst can be recycled five times without an appreciable loss of activity. The bond-, regio-, and stereoselectivity parameters were investigated in the oxidation of different alkane substrates (n-hexane, n-heptane, n-octane, methylcyclohexane, adamantane, cis- and trans-1,2-demethylcyclohexane), and the obtained results were compared with the homogeneous systems based on the Cu-4 catalyst. In particular, the high bond selectivity parameters detected in the oxidation of methylcyclohexane (1 degrees:2 degrees:3 degrees of 1:8:142) and adamantane (2 degrees:3 degrees of 1:21) catalyzed by Fe3O4@mSiO(2)@Cu-4 suggest that the reactions possibly occur in hydrophobic pockets of the nanocatalyst. (C) 2016 Elsevier B.V. All rights reserved.

A group of 5 new peroxomolybdates was synthesized and characterized. All the compounds belong to the group of oxidodiperoxidomolybdenum compounds, with a pyridine carboxylic acid N-oxide moiety coordinating the Mo atoms. They were investigated using single crystal or powder X-ray diffraction techniques. The obtained compounds were additionally characterized by IR spectroscopy and their thermal stability was studied by XRPD methods. The synthesized peroxomolybdates exhibit catalytic activity in the oxidation of cyclooctane with molecular oxygen.

Sesquiterpenoids constitute a marvelously varied group of natural products that feature a vast array of molecular architectures. Among them, the unusual bicyclo [6.3.0] undecane sesquiterpenoids are one of the most representative. To date, only approximately 42 naturally occurring compounds with this unique scaffold, which can be classified into seven different groups, have been reported. As the first-found member of each type, dactylol, asteriscanolide, dumortenol, toxicodenane C, and capillosanane S are characteristic of the four methyl groups on the five-eight-membered ring system. Only 11-hydroxyjasionone and sinuketal decorate the core with an isopropyl group. These natural products exhibit a wide range of bioactivities, including antifouling, anti-inflammatory, immune suppression, cytotoxic, antimutagenic, antiplasmodial, and antiviral activities. It was noted that some total syntheses of precapnellane-sesquiterpenoids (dactylol, poitediol, precapnelladiene), asteriscanolide, and 11-hydroxyjasionone have been achieved, because their cyclooctanoid core represents an important target for the development of synthetic strategies to prepare eight-membered ring-containing compounds. This review focuses on these natural sesquiterpenoids and their biological activities and synthesis, and aims to provide a foundation for further research of these interesting compounds.

The search for new transition metal based catalytic systems that are active in the oxidative functionalization of such inert substrates as saturated hydrocarbons continues to be an important research direction in molecular catalysis. In the present study, two new copper(II) coordination compounds, namely a discrete dimer [Cu2(μ-H2tea)2(nfa)2]·2H2O (1) and a 1D coordination polymer [Cu2(μ-H2tea)2(μ-Htma)]n·4nH2O (2) were synthesized and applied as homogeneous catalysts for the mild oxidative functionalization of cycloalkanes (cyclopentane, cyclohexane, cycloheptane, and cyclooctane). Both products 1 and 2 were self-assembled in aqueous medium from copper(II) nitrate, triethanolamine (H3tea), sodium hydroxide, and 2-naphthoic (Hnfa) or trimesic (H3tma) acids, isolated as stable crystalline solids, and fully characterized by standard methods including single-crystal X-ray diffraction. Their structures feature a similar type of dicopper(II) triethanolaminate cores that are decorated by terminal or bridging aromatic carboxylate ligands. Two model catalytic reactions were investigated, namely the oxidation of cycloalkanes by H2O2 to produce cycloalkyl hydroperoxides as intermediate products and then a mixture of cyclic alcohols and ketones as final products, and the carboxylation of cycloalkanes with CO/S2O82−/H2O to form cycloalkanecarboxylic acids as main products. These model reactions undergo under very mild conditions (50−60 °C) and show good efficiency. Substrate scope, selectivity features, and the effects of reaction parameters were investigated and discussed in detail. This study widens the family of multicopper(II) cores capable of catalyzing the oxidative functionalization of saturated hydrocarbons under mild conditions.

This work reports on the synthesis of several new complexes of Ir supported by a diarylboryl/bis(phosphine) PBP pincer ligand. The previously reported complexes (PBP)Ir(Ph)(Cl) (1) and (PBP)Ir(H)(Cl) (2) were converted to the new complexes (PBP)IrH4 (3) and (PBP)Ir(Ph)(H) (4). Complexes 3 and 4 serve similarly as precatalysts for transfer dehydrogenation of cyclooctane. The turnover numbers achieved were relatively modest but were increased (to 220 at 200 °C) when 1-hexene was used as a sacrificial hydrogen acceptor vs tert-butylethylene. The dicarbonyl complex (PBP)Ir(CO)2 (6) was also synthesized, by the reaction of CO with either 3 or 4. Intermediates (PBPhP)Ir(H)(CO)2 (5) and (PBP)IrH2(CO) (7) were observed in these reactions. Complex 7 could be obtained in pure form by comproportionation of 3 and 6. Solid-state structures of 3 and 6 were determined by X-ray crystallography.

Transition metal [M = Co(II), Cu(II)] complexes of H 2 L 1 and H 2 L 2 ligands have been prepared as neat and nanohybrid zeolite-Y immobilized complexes. The various analytical tools such as FTIR, ICP-AES, elemental analysis, UV–vis, Brunauer, Emmett and Teller (BET) surface area analysis, Thermal analysis, scanning electron micrographs, Powder XRD, conductivity, magnetic moment, and AAS were employed for the characterization of the prepared catalysts. Among all catalysts, the [Cu(L 1 )]-Y (heterogeneous) and [Cu(L 1 )] (homogeneous) have offered high activity and selectivity over oxidation of cyclohexene. Moreover, the [Cu(L 1 )] and [Cu(L 1 )]-Y were employed as catalyst over various organic substrates at identical reaction condition. The immobilized catalyst [Cu(L 1 )]-Y is found to be moderate active over oxidation of cyclohexane (75.2%,), benzene (8.21%), phenol (14.5%), styrene (87.5), benzyl alcohol (21.5%), limonene (11.2%), α-pinene (9.15%), and cyclooctane (76.8%) with high TON values (21942-2054). The mechanistic study using UV–vis and FTIR suggests the participation of active metalperoxo species, which is reinforced by its high catalytic activity over limonene (16.3%) in the absence oxidant.

A series of new (tBu2PSCOPR2)IrHCl iridium complexes with ‘hybrid’ phosphinothious-phosphinite PSCOP ligands ([tBu2PSCOPR2 = 1-(SPtBu2)-3-(OPR2)-C6H4], R = tBu, 4a, R = Cy, 4b, R = iPr, 4c, and R = Et, 4d) have been synthesized and characterized. Treatment of complexes 4a–d with sodium tert-butoxide generates the active species for catalytic transfer-dehydrogenation of cyclooctane (COA) or n-octane using tert-butylethylene (TBE) as hydrogen acceptor to form cyclooctene (COE) or octenes, respectively. The catalytic activity of these complexes and the product selectivity in alkane dehydrogenation is greatly influenced by the steric properties of the pincer ligand. In general, the less sterically bulky complex exhibits higher catalytic activity than the more hindered complex. Among the new (PSCOP)Ir-type complexes, the least crowded complex (tBu2PSCOPEt2)IrHCl 4d is most active for n-octane/TBE transfer-dehydrogenation. The relatively crowded, less active, complexes (tBu2PSCOPtBu2)IrHCl (4a) and (tBu2PSCOPCy2)IrHCl (4b) exhibit high regioselectivity for α-olefin formation at the early stages of the reaction.

An efficient and potentially scalable method is described for the synthesis of the silica-supported complexes [(≡Si–O−)WMe5] and [(≡Si–O−)WMe2(≡CH)] obtained by in situ alkylation of the surface-grafted tungsten chloride [(≡Si–O−)WCl5] (1). [(≡Si–O−)WCl5] can be readily prepared by the reaction of commercially available and stable tungsten hexachloride WCl6 with partially dehydroxylated silica at 700 °C (SiO2-700). Further reaction with ZnMe2 at room temperature rapidly forms a mixture of surface-alkylated tungsten complexes. They were fully characterized by microanalysis, FTIR, mass balance, and solid-state NMR (1H, 13C, 1H–13C HETCOR, 1H–1H double quantum and triple quantum) and identified as [(≡Si–O−)WMe5] and another product, [(≡Si–O−)WMe2(≡CH)]. The latter might have been generated by partial decomposition of the tungsten methyl chloride compound, which is formed during the stepwise alkylation of [(≡Si–O−)WCl5]. DFT calculations were carried out to check the relative stability of the tungsten methyl ...

The selective oxidation of hydrocarbons is a main academic and industrial research challenge. A lot of researches have been done about this issue, but till now relatively little attention has been paid to graphene-complex oxide nanocomposites. Herein, we report our studies on a new catalyst. Silver ferrite–graphene (AgFeO 2 –G) as a separable nanocomposite from the reaction solution, was used as an effective oxidizing agent for the oxidation of various hydrocarbons (1- decene, cyclohexene, cis-cycloctene, cyclohexane, cyclooctane etc.) under mild conditions (55 ০ C, 8 h) with high conversion and selectivity using air, that is proper for ‘green’ chemistry. Metal or metal oxide nanoparticles assembled on graphene sheets revealed high electrocatalytic activity. Indeed, AgFeO 2 with graphene due to low band gap and graphene oxide with large amounts of oxygen-containing groups, provide facility catalytic activity of catalyst-supported system. We also found that, with this catalyst, selective oxidation could be achieved without the need for the addition of solvent, which is appropriate in particular for ‘green’ chemistry. The catalysts showed little deactivation and maintained their conversion and selectivity levels duration of the measurements.

Vapor–liquid equilibria at 298.15 K have been determined for binary mixtures of tetrachloromethane or heptane plus a cyclic hydrocarbon (cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclodecane, cis-decalin, norbornane, octahydro-4,7-methano-1H-indene, adamantane), using a head-space gas chromatographic technique. Excess molar Gibbs energies and activity coefficients for the systems investigated have been obtained by a least-squares treatment of the equilibrium results. All mixtures exhibit positive deviations from ideality, increasing with the cycloalkane size. The Gibbs energies of solvation, Δsolv G°, for cyclic hydrocarbons in the two solvents have been evaluated and compared with those of linear and branched alkanes. The effect of cyclization upon Δsolv G° has been discussed.

Medium sized rings and even small cyclic molecules have always challenged our static insights on them. They have thus forced us to propose models with conformers, connected in terms of energy and interconversions. The wheel-model of Lipnick et al. as well as the onion models of Hendrickson et al. are among the most sensible and sophisticated responses to such a demand. Here, DFT-ωb97xd/ 6–311 + G* computations confirmed by MP2/aug cc-pVTZ computations were used to fully investigate the energy, vibrations and full dynamics of 24 conformers. Then spherical conformational landscape SCL model was used to plot the conformational dynamics in cyclooctane for the first time. Classifications were done by a close inspection of the whole cast of conformers in cyclooctane, cyclopentane and cyclohexane. The fluxional Twist/Boat T/B ring coordinates were found to be a common feature in all the cyclic molecules studied. A new pictorial notion is suggested to present twist and boat conformers for all cyclic molecules in a generic sense. The simple, precise and universal conformational types presented here, unifies our perception of conformational dynamics in cyclic molecules, and paves the path towards a better analysis of cyclic motifs in natural products and bio-functional conformers.

The coexistence curves of liquid-liquid equilibrium (LLE) for the mixtures: phenylacetonitrile + heptane, + octane, + nonane, + cyclooctane, or + 2,2,4-trimethylpentane and for 3-phenylpropionitrile + heptane, or + octane are reported. Aromatic nitrile + alkane, + aromatic hydrocarbon or + 1 alkanol systems are investigated using a set of thermophysical properties: phase equilibria (solid-liquid, SLE, vapour-liquid, VLE and LLE), excess molar functions, enthalpies (), isochoric internal energies (), isobaric heat capacities () and volumes (), and the Kirkwood’s correlation factor. Due to proximity effects between the phenyl and the CN groups, dipolar interactions between molecules of aromatic nitriles are stronger than those between molecules of isomeric linear nitriles. Dipolar interactions become weaker in the order: 3-phenylpropionitrile > phenylacetonitrile > benzonitrile. Benzonitrile + aromatic hydrocarbon mixtures are characterized by dispersive interactions and structural effects. The latter are more important in systems with phenylacetonitrile. Structural effects are also present in benzonitrile + n-alkane, or + 1-alkanol + mixtures. The systems mentioned above have been studied using DISQUAC. Interaction parameters for contacts where the CN group in aromatic nitriles participates are given. DISQUAC describes correctly any type of phase equilibria, of benzonitrile + hydrocarbon mixtures and of benzonitrile + cyclohexane, or 1-alkanol systems. Large differences encountered between theoretical values and experimental data for some solutions are discussed. 1-Alkanol + benzonitrile mixtures are also investigated by means of the ERAS model. ERAS represents well of these systems. The curves of solutions with longer 1-alkanols are more poorly described, which has been explained in terms of the existence of structural effects., Consejería de Educación y Cultura of Junta de Castilla y León, under Project BU034U16

The fluorinated cyclopentadienyl complexes [Rh(η5-C5H4CH2CH2C6F13)(CO)2] (2), [Rh(η5-C5H4CH2CH2C8F17)(CO)2] (3), [Rh(η5-C5H4CH2CH2C10F21)(CO)2] (4), [Rh(η5-C5H4CH2CH2CnF2n+1)(CO)(PEt3)] (7: n = 6; 8: n = 8; 9: n = 10) and [Rh(η5-C5H4CH2CH2CnF2n+1)(CO){P(CH2CH2C6F13)3}] (10: n = 8; 11: n = 10) were synthesized and their reactivity was investigated. Compound 3 converts at room temperature into the trinuclear complex [Rh2(η5-C5H4CH2CH2C8F17)2(μ-CO)2Rh(η5-C5H4CH2CH2C8F17)(CO)] (6). The complexes 9 and 11 were employed in dehydrogenation reactions of cycloalkanes in C6F14/hydrocarbon mixtures. Photocatalytic conversions were observed and a turnover number of 16 for the dehydrogenation of cyclooctane with complex 11 was obtained.

Excess molar enthalpies, HE, for octane isomers (n-octane, isooctane and cyclooctane) + heterocycles (morpholine, 1,4-dioxane, piperidine, oxane and N-methyl piperidine) or + cyclohexane binary mixtures, were determined at 308.15 K and atmospheric pressure, using a flow calorimeter. All the mixtures are endothermic, over the whole range of compositions, except cyclooctane + cyclohexane which presents very small, positive and negative, excess molar enthalpies. HE values fall as follows: morpholine > 1,4-dioxane > piperidine > oxane > N-methyl piperidine > cyclohexane and n-octane > isooctane > cyclooctane. The purely physical model, DISQUAC, based on the rigid lattice theory developed by Guggenheim, was relatively well tested.

An iPr-substituted PBP-pincer ligand was synthesized and introduced to iridium metal to give iPr-(PBP)Ir(H)Cl and iPr-(PBP)Ir(C2H4) complexes. Both of these complexes were found to be moderately active for the catalytic transfer dehydrogenation of cyclooctane.

A series of iridium PCsp3P complexes based on bis(2-diisopropylphosphinophenyl)-2-anisoylmethane (PCanisHP) is reported. (PCanisP)Ir(H)Cl was generated from the C–H activation of the backbone by [Ir(COD)Cl]2 (COD = 1,5-cyclooctadiene), while the dihydride (PCanisP)Ir(H)2 was generated by hydride metathesis from (PCanisP)Ir(H)Cl. Both complexes are 18e octahedral complexes and water stable. The hemilability of the anisole tether was probed using CO and PMe3; multiple isomers, in which the anisole substituent was displaced, were generated, showing the flexibility of the ligand backbone. (PCanisP)Ir(H)2 showed deuterium incorporation in the hydride, backbone, and anisole positions upon moderate heating in C6D6. Both (PCanisP)Ir(H)Cl and (PCanisP)Ir(H)2 were precatalysts for transfer dehydrogenation of cyclooctane under moderate conditions.

A multifunctional organic–inorganic hybrid based on a Cu coordination polymer capped polyoxometalate (H3PMo12O40) designated as compound 1 with [CuI(4,4′-bipy)]3[PMo 10 VI Mo 2 V O40{CuII(2,2′-bipy)}] formula was prepared using CuCl2·2H2O, 4,4′-bipy, 2,2′-bipy and H3PMo12O4 in water under hydrothemal conditions. The prepared compound 1 was characterized by FTIR, XRD and chemical analysis techniques. It was found that the compound successfully catalyzes the epoxidation of various alkenes such as diphenyl ethylene, trans-stilbene, cyclohexene, norbornene, styrene and cyclooctene and oxidation of alkanes such as fluorene, adamantane, diphenylmethane, cyclohexane and cyclooctane, in acetonitrile with 20–99 % conversion and 53–100 % selectivity with tert-butyl hydroperoxide as oxidant under optimized condition. This heterogeneous catalyst could be easily recovered and reused after reaction without loss of activity.

The selective aliphatic carbon–carbon activation of cyclo-octane (c-octane) was achieved via the RhII(ttp)-catalyzed 1,2-addition of Rh(ttp)H to give Rh(ttp)(n-octyl) (ttp = tetratolylporphyrinato dianion) in good yield under mild reaction conditions. This mechanism is further supported by DFT calculations. The reaction worked only with the sterically accessible Rh(ttp) porphyrin complex but not with the bulky Rh(tmp) system (tmp = tetrakismesitylporphyrinato dianion), thus showing the highly steric sensitivity of carbon–carbon bond activation by transition metal complexes.

A series of imidazolinium-based CCC pro-ligands featuring N-Mes, Dipp, iPr and tBu substituents (1·2HCl) have been prepared. The corresponding free carbenes are readily generated through deprotonation by strong bases and, in addition to being characterised in situ by 1H and 13C NMR spectroscopy, were trapped through reaction with CuCl. Iridium pincer compounds of the N-Mes (5a) and N-Dipp (5b) substituted ligands, viz. [Ir(1)HCl(NCMe)], were obtained through reaction between the respective pro-ligand, [Ir(COE)2Cl]2, and Et3N in acetonitrile at ca. 80 °C. Under similar conditions the N-iPr and N-tBu analogues were not formed. The new iridium pincer complexes 5a and 5b were fully characterised in solution, by NMR spectroscopy and ESI-MS, and in the solid-state by X-ray diffraction. Under relatively forcing reaction conditions neither 5a nor 5b, in combination with KOtBu, show any significant catalytic activity for the transfer dehydrogenation of cyclooctane to cyclooctene using tert-butylethylene as the sacrificial hydrogen acceptor (ca. 2 TONs, 150 °C, 24 h).\ud \ud

The majority of the known pincer iridium based catalysts for dehydrogenation of alkanes has arene-based backbones. Here, the catalytic activity of aliphatic iridium pincer complexes, viz, the cyclohexane-based phosphine complex (PCyP)IrHCl (4) (PCyP = {cis-1,3-bis-[(di-tert-butylphosphino)methyl]cyclohexane}(-)) and the 2-methylpropane-based phosphinite complex (POCOP)IrHCl (5) (POCOP = 1,3-bis-(di-tert-butyl-phosphinito)-2-methylpropane(-)), in dehydrogenation of cyclooctane and triethylamine was studied. They give TONs that are in the range of 0-200. In addition, improved procedures for synthesis and metallation of the PCyP ligand (3) are presented. (C) 2014 Elsevier Ltd. All rights reserved.

A new arsenic-based pincer (AsOCOAs) dehydrogenation catalyst has been synthesized, IrHCl{2,6-C6H3-(O-AsBut2)} (3). Treatment with an equivalent of base (NaO-tert-butoxide) under an atmosphere of hydrogen gas affords the dihydride catalyst IrH2{2,6-C6H3-(O-AsBut2)} (4). The activity of 3 was explored under transfer dehydrogenation conditions with cyclooctane and tert-butyl ethylene, giving a maximum turnover number of 960 at 175 °C in 24 h. Acceptorless dehydrogenations were also explored with pyrrolidine-based molecules, ethylperhydrocarbazole (5), methylperhydroindole (6), and butylpyrrolidine (7), in which all results indicate 3 is roughly half as active as the analogous phosphine-based pincer catalyst 2. Akin to the phosphine pincer catalysts the activity was seen to steadily improve with increasing temperature, peaking at 175 °C, upon which thermal decomposition sets in.

Iridium complexes of CCC-pincer bis-N-heterocyclic carbenes, including a newly synthesized trifluoromethyl-substituted complex, were examined as catalysts for the acceptorless dehydrogenation of cyclooctane and n-undecane. Up to 103 turnovers were observed for the dehydrogenation of cyclooctane, and up to 97 turnovers were observed for the dehydrogenation of n-undecane. The catalysts showed high initial turnover frequencies, followed by a gradual loss of activity over 24 h. Experiments indicate that this loss of activity is due to catalyst decomposition rather than product inhibition. Stoichiometric reactivity was investigated for the precatalysts, focusing on the synthesis of dihydride and trihydride complexes as well as the dissociation and addition of neutral ligands.

The nucleophilic esterification of 5- and 7-membered N-phenylcyclic ammonium salts resulted in distinctive regioselectivity, despite their comparable ring strain in the ground states relative to the corresponding cyclopentane and cycloheptane (both 25.9 kJ mol(-1)). The former underwent a selective ring-opening reaction, while the latter predominantly underwent ring-emitting with concurrent ring-opening reactions. A DFT study of the model compounds revealed that the regioselection in the 5- and 7-membered azacycloalkane quaternary salts is plausibly directed by the transition state ring conformation, and not by the ground state ring strain. Remarkably, at the ring-opening transition state, the 5-membered cyclic skeletal structure expands toward the unstrained and thus less frustrated 6-membered cyclohexane conformation. On the other hand, the 7-membered counterpart expands at the ring-opening transition state toward the more frustrated 8-membered cyclooctane conformation to promote the alternative ring-emitting process.

In this paper, the evaluation of the ionic liquid 1-ethylpyridinium ethylsulfate, [Epy][ESO 4 ], on the extraction of benzene from cyclic hydrocarbons was carried out. With the aim of studying the influence of the cyclic hydrocarbon structure on the liquid extraction, the liquid–liquid equilibria (LLE) data of the systems: {cyclohexane, or cyclooctane, or methylcyclohexane or cyclohexene (1) + benzene (2) + [Epy][ESO 4 ] (3)} have been experimentally determined at T = 298.15 K and atmospheric pressure. Selectivity and solute distribution ratio, derived from the tie-lines, were used to determine the ability of this ionic liquid as solvent for the separation of benzene from its mixtures with cyclic hydrocarbons. The degree of consistency of the tie-lines was tested using the Othmer-Tobias equation, and the experimental LLE data were correlated using the Non-Random Two-Liquid (NRTL) model. Furthermore, the literature comparison for the system {cyclohexane (1) + benzene (2) + ionic liquid or solvent (3)} has been performed. The quantum chemical based COnductor like Screening MOdel for Real Solvent (COSMO-RS) model was used as a predictive tool to describe the experimental LLE data for the ternary systems {cyclohexane, or cyclooctane, or methylcyclohexane, or cyclohexene (1) + benzene (2) + [Epy][ESO 4 ] (3)} and the obtained results have been compared with the experimental data.

This work compares the extent of reversibility and the thermodynamics of adsorption (Kads, ΔG°ads) of room-temperature vapors of common environmentally relevant monoterpenes (α-pinene, β-pinene, limonene, and 3-carene) and industrially relevant cyclic and acyclic non-terpene hydrocarbons (cyclohexane, hexane, octane, and cyclooctane) to fused silica surfaces. Vibrational sum frequency generation spectroscopy carried out in the C–H stretching region shows negligible surface coverage-dependent changes in the molecular orientation of all species surveyed except for cyclohexane. The group of monoterpenes studied here distinctly exhibits partially reversible adsorption to fused silica surfaces compared to the group of non-terpene hydrocarbons, demonstrating a link between molecular structure and adsorption thermodynamics. The standard Gibbs free energy of adsorption is nonlinearly correlated with the equilibrium vapor pressure of the compounds surveyed.

In the presence of an iridium 3,4,7,8-tetramethyl-1,10-phenanthroline catalyst, a methyl group on the silicon atom of alkyltrimethylsilanes undergoes selective C–H borylation with bis(pinacolato)diboron in cyclooctane at 135 °C to give alkyl(borylmethyl)dimethylsilanes. The C–H borylation of tetramethylsilane takes place efficiently at 100 °C. Permethyloligosilanes can also undergo C–H borylation without cleavage of the Si–Si bonds.

Three new oxodiperoxomolybdenum complexes with nicotinic acid have been synthesized and charac- terized with the use of single-crystal analysis, XRPD versus temperature, TG/DSC, SEM and IR spectros- copy. The investigated compounds are: 1 – (NH 4 ) 2 [MoO(O 2 ) 2 .N-nicO] 2 , 2 – (nicH) 2 [MoO(O 2 ) 2 .N- nicO] 2 2(H 2 O), 3 – MoO(O 2 ) 2 (H 2 O)nicH; (N-nicO, nicH denote nicotinic acid N-oxide and protonated nicotinic acid, respectively). Compounds 1, 2 are salts of the same acid with cyclic dinuclear anions, whereas compound 3 can be regarded as an inner salt. Compounds 1–3 are stable in ambient conditions, the respective percentages of oxygen in peroxo groups are 19.21%, 14.06% and 20.19%, respectively. Above 125 ° C peroxo compounds 1–3 decompose, forming nanometric MoO 2 and MoO 3 . TG/DSC curves reveal clear effects connected with the release of oxygen and strong exothermic effects connected with final loss of organic components. All the investigated complexes were found to be active in the oxidation of cyclooctane to cyclooctanone and cyclooctanol with molecular oxygen.

The densities and viscosities of the regular quinary system: benzene (1) + toluene (2) + ethylbenzene (3) + heptane (4) + cyclooctane (5), and all its corresponding quaternary sub-systems were measured over the entire composition range at 293.15 and 298.15 K. Kinematic viscosity–composition data reported in the present study were utilized to test the predictive capability of some well-known viscosity models. The models subjected to testing were: the predictive version of the McAllister’s three-body model, a generalized corresponding states principle, the group contribution GC-UNIMOD method, and the Allan and Teja correlation. Results of testing these models led to an overall AAD (%) of 1.20 for the one quaternary system that did not contain cyclooctane, and an overall AAD (%) of 8.59 for the remaining cyclooctane-containing systems. For the quinary system, the overall AAD (%) was found to be 2.92; the last two values were calculated using the value of cyclooctane of 10.595.

[Co3(PDMT)Cl6] complex, in which PDMT isN,N′,N″-tris(2-pyrimidinyl)dimethylentriamine was prepared in cyclohexanol under hydrothermal condition. At first, the crystal structure of PDMT was solved based on the Rietveld method by using laboratory X-ray powder diffraction data. The molecular geometry of the ligand and complex were optimized by B3LYP method. In order to heterogenize the prepared complex, it was immobilized on the modified Fe3O4nanoparticles with (3-aminopropyl)trimethoxysilane (APTMS). The prepared compound designated as Fe3O4@SiO2-2@APTMS@[Co3(PDMT)Cl6] was found to successfully catalyze the epoxidation of cyclooctene, styrene, cyclohexene,trans-stilbene as well as oxidation of fluorene, diphenylmethane, ethylbenzene, adamantane, cyclohexane, cyclooctane and norbornene with TBHP as oxidant with 25–100% conversions and 18–100% selectivities. Ligand, complex and Fe3O4@SiO2-2@APTMS@[Co3(PDMT)Cl6] were characterized by FT-IR, TEM, XRD, Mass, UV–Vis, DSC-TGA, NMR, GC and GC–Mass techniques.

The aim of this work was to study the effect of substituents on the catalytic activity of iron μ-oxo porphyrins in oxidation of cycloalkanes. Electron-donating or electron-withdrawing substituents were introduced in meso-aryl groups of iron μ-oxo porphyrins. An important part of the work was the characterization of the catalysts, in particular their redox properties. Catalytic performance and selectivity were evaluated using cyclopentane, cyclohexane, and cyclooctane as model compounds. It was shown that not only electron-withdrawing but also electron-donating substituents improved the catalytic performance of iron μ-oxo complexes. Moreover, catalytic activity of iron μ-oxo porphyrins with electron-withdrawing substituents correlated with the half-wave potential E1/2 while the catalytic activity of iron μ-oxo porphyrins with electron-donating substituents increased with the decrease of reduction potential ERED.

The reactivity of thiophene (T), 2-methylthiophene (2-MeT), and benzothiophene (BT) with [Ir(cod)(IPr)(L)]BF complexes (L = acetone (1), pyridine (2) or dimethylphenylphosphine (3); IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) in the presence of molecular hydrogen has been investigated. Under these conditions the 1,5-cyclooctadiene ligand is hydrogenated to cyclooctane, which renders an unsaturated species (Ir-IPr-L) able to coordinate the thiophene moiety. The coordination mode of T, 2-MeT, and BT depends on the nature of the substrate and the ligand trans to the IPr (L). The reaction of 1 with T and 2-MeT leads to dissociation of the acetone ligand to afford the complexes [Ir(H)(IPr)(η--T)]BF (4) and [Ir(H)(IPr)(η--2-MeT)(η-S-2-MeT)]BF (5), respectively, but no stable complex is observed on reaction with BT. Analogously to 1, complex 2 does not give a stable complex on reaction with BT, while reaction with 2-MeT yields complex 5 again. Conversely, reaction with T affords a mixture of complexes, [Ir(H)(IPr)(η--T)(Py)]BF (6) and [Ir(H)(IPr)(η-S-T)(Py)]BF (6′), both featuring a coordinated pyridine ligand. The reaction of 3 with T, 2-MeT, and BT yields in all cases η-S complexes, namely [Ir(H)(IPr)(η-S-T)(PPhMe)]BF (7), [Ir(H)(IPr)(η-S-2-MeT)(PPhMe)]BF (8) in equilibrium with [Ir(H)(IPr)(η-S-2-MeT)(PPhMe)]BF (8′), and [Ir(H)(IPr)(η-S-BT)(PPhMe)]BF (9). Finally, DFT calculations were employed to rationalize the coordination modes of T, 2-MeT, and BT, as well as the tendency of these complexes to undergo hydrogenation instead of hydrogenolysis of the thiophene moiety under catalytic conditions., The authors acknowledge the support by the Ministry of Higher Education, Saudi Arabia, in establishment of the Centre of Research Excellence in Petroleum Refining & Petrochemicals at KFUPM (KACST-funded project ART-32-68). The support of the KFUPM under the KACST funded project (ART-32-68) and the KFUPM−University of Zaragoza research agreement are also highly appreciated. This work was further supported by the Spanish Ministry of Economy and Competitiveness (MINECO/FEDER) (CONSOLIDER INGENIO CSD2009-0050, CTQ2011-27593, and CTQ2012-35665 projects) and the Diputación General de Aragón (DGA/FSE-E07).

Rate constants for the reactions of Cl atoms with cycloheptane, cyclooctane, cyclodecane, cyclohexanone, cycloheptanone, cyclooctanone, and cyclodecanone have been measured at 297 ± 2 K and atmospheric pressure of air using a relative rate method. n-Butane, with a rate constant of 2.05 × 10−10 cm3 molecule−1 s−1, was used as the reference compound, and the rate constants obtained (in units of 10−10 cm3 molecule−1 s−1) were cycloheptane, 4.22 ± 0.15; cyclooctane, 4.57 ± 0.15; cyclodecane, 5.13 ± 0.15; cyclohexanone, 1.79 ± 0.06; cycloheptanone, 2.46 ± 0.07; cyclooctanone, 2.97 ± 0.09; and cyclodecanone, 3.65 ± 0.15, where the indicated errors are two least-squares standard deviations and do not include uncertainties in the rate constant for the reference compound n-butane. Room temperature rate constants for the C5–C10 cycloketones indicate that the CH2 groups adjacent to the carbonyl group are almost totally deactivated toward H-atom abstraction by Cl atoms, and this also applies to acyclic ketones. A previous structure–reactivity relationship for Cl + alkanes has been extended to include acyclic and cyclic ketones. © 2012 Wiley Periodicals, Inc. Int J Chem Kinet 45: 52–58, 2013

The densities and kinematic viscosities of binary and ternary regular mixtures containing cyclohexane, m -xylene, chlorobenzene, cyclooctane and decane were measured over the entire composition range at 308.15 K and 313.15 K, respectively. The experimental results were used to test the predictive capability of the six viscosity models available in the literature; namely, the generalized McAllister three-body interaction model, the pseudo -binary McAllister model, the group contribution (GC-UNIMOD) model, the generalized corresponding states principle (GCSP) model, the Allan and Teja correlation and the Grunberg and Nissan law of viscosity. The percentage average absolute deviation (%AAD) was employed as the criterion for comparing the predictive capabilities of the aforementioned models. The experimental pure component data obtained in the present study agreed well with the corresponding literature values at both designated temperatures. The model testing results showed that the generalized McAllister showed the best predictive capability resulting in the lowest %AADs; viz., 3.3 and 3.7 at 308.15 K and 313.15 K, respectively.

The heterometallic complex [Co(4)Fe(2)OSae(8)]·4DMF·H(2)O (1) was synthesized by one-pot reaction of cobalt powder with iron chloride in a dimethylformamide solution of salicylidene-2-ethanolamine (H(2)Sae) and characterized by single crystal X-ray diffraction analysis, magnetic measurements, high frequency electron paramagnetic resonance (HF-EPR), and Mössbauer spectroscopies. The exchange coupling in the Fe(III)-Fe(III) pair is of antiferromagnetic behavior with J/hc = -190 cm(-1). The HF-EPR spectra reveal an unusual pattern with a hardly detectable triplet signal of the Fe(III) dimer. The magnitude of D (ca. 13.9 cm(-1)) was found to be much larger than in related dimers. The catalytic investigations disclosed an outstanding activity of 1 toward oxidation of cycloalkanes with hydrogen peroxide, under mild conditions. The most efficient system showed a turnover number (TON) of 3.57 × 10(3) with the concomitant overall yield of 26% for cyclohexane, and 2.28 × 10(3)/46%, respectively, for cyclooctane. A remarkable turnover frequency (TOF) of 1.12 × 10(4) h(-1) (the highest initial rate W(0) = 3.5 × 10(-4) M s(-1)) was achieved in oxidation of cyclohexane. Kinetic experiments and selectivity parameters led to the conclusion that hydroxyl radicals are active (attacking C-H bonds) species. Kinetic and electrospray ionization mass spectrometry (ESI-MS) data allowed us to assume that the trinuclear heterometallic particle [Co(2)Fe(Sae)(4)](+), originated from 1 in solution, could be responsible for efficient generation of hydroxyl radicals from hydrogen peroxide.

This article reports adhesion interactions between silicon-supported dichlorotriazine films in various solvents. The formation, chemical composition, and thickness of the overlayer were analyzed by means of X-ray photoelectron spectroscopy (XPS). An atomic force microscopy (AFM) characterization was performed to evaluate the overlayer roughness. Adhesion interactions were measured using chemical force spectrometry (CFS). The purpose of the study is to understand the effect of solvents on the adhesion force between dichlorotriazine films. The tip–surface adhesion forces measured in octane and cyclooctane were found to be relatively weak. Use of solvents that may participate in π–π interactions, such as toluene and trifluoromethyl benzene, as well as a potential monohalogen bond donor, such as CCl4, did not lead to significant increase in the tip–surface forces. However, the adhesion forces increase considerably when measured in solvents that contain at least two ether groups, such as dioxane, diethylene gl...

Reactions of [(η5-R)Rh(CO)2] (R = cp, ind) with water-soluble phosphines (L = 1,3,5-triaza-7-phosphaadamantane and tris(2-cyanoethyl)phosphine) give the new rhodium(I) complexes of the types [Rh(η5-cp)(CO)(PTA)] (1), [Rh(η5-cp)(CO)(P(CH2CH2CN)3)] (2), [Rh(η5-ind)(CO)(PTA)] (3) and [Rh(η5-ind)(CO)(P(CH2CH2CN)3)] (4) in isolated yields of 52–75%. All these compounds have been fully characterized by IR, 1H, 31P{1H} and 13C{1H} NMR, FAB-MS spectroscopies and elemental analyses. Reactivity for the substitution of phosphine is greater for [(η5-ind)Rh(CO)(L)] comparing to [(η5-cp)Rh(CO)(L)] because of a flexibility of the indenyl ligand to undergo facile η5–η3 coordinative isomerizations. The obtained complexes are active catalyst precursors for the dehydrogenation of propan-2-ol, octane and cyclooctane under photoassisted conditions without any organic hydrogen transfer acceptors, giving TOFs of 26–56 using 3 as precatalyst.

The reaction of 1,3-bis(imidazolyl)benzene with excess 1-bromoadamantane at 170 °C for 14 h afforded 1,3-bis(1-adamantylimidazolium)benzene dibromide (1), which was characterized by IR, NMR, and X-ray diffraction. Metathetical anion exchange with excess sodium iodide yielded the N-heterocyclic dicarbene precursor 1,3-bis(1-adamantylimidazolium)benzene diiodide, (CHimidCHCHimid)I2 (2), in high yield. The reaction of [Ir(μ-Cl)2(cod)]2 (cod = 1,5-cyclooctadiene) with 2 in the presence of 2.2 equiv of Cs2CO3 in refluxing acetonitrile led to the formation of the unsymmetrical iridium(III) hydride pincer complex [Ir(H)I(CNHCCCaNHC)(NCMe)] (3), which contains a C2-bound NHC ligand and a C5-bound NHC ligand. Recrystallization of 3 from ClCH2CH2Cl/Et2O generated the dihalide Ir(III) pincer complex [IrX2(CNHCCCaNHC)(NCMe)], where X = mixture of I and Cl (4). Its formation probably involves initial formation of an iridium chloro iodo intermediate via solvent-induced substitution of the hydride ligand of 3 by chlorid...

The synthesis and reactivity of a series of Ru(II) complexes based on the strongly π-accepting pincer ligand 1,3-C6H3(CH2P(CF3)2)2 (CF3PCP) is reported. Thermolysis of [Ru(cod)(η3-2-methylallyl)2] with CF3PCPH under H2 affords a mixture of the three complexes (μ-CF3PCPH)Ru(H)(μ-H)(μ-η6,κ3-CF3PCP)Ru(H), [(CF3PCP)Ru(H)]2(μ-CF3PCPH)2, and (CF3PCP)Ru(cod)H, which were structurally characterized and individually prepared in moderate yields. (CF3PCP)Ru(cod)H reacts with (C2F5)2PCH2CH2P(C2F5)2 (dfepe) to give (CF3PCP)Ru(dfepe)H. (CF3PCP)Ru(cod)H is moderately active as an alkane dehydrogenation catalyst. Thermolysis in 1:1 mixtures of cyclooctane and tert-butylethylene at 150 and 200 °C resulted in initial rates of 180 and 1000 turnovers h–1 of cyclooctene, respectively. Acceptorless dehydrogenation of cyclooctane also occurs, with an initial rate of 14 turnovers h–1. The decrease of catalyst activity over time was found to be due to thermal catalyst decomposition rather than product inhibition by cyclooctene.

A novel two-dimensional 3d–4d transition metal-based coordination polymer [VO(OCH3)(OHCH3)(L)Ag(NO3)]∞ (1) has been synthesized and characterized by single crystal X-ray diffraction and fluorescence spectroscopy (H2L = (E)-N′-(2-hydroxybenzylidene)isonicotinohydrazide). The coordination sphere of each V center is octahedral and chelates to a tridentate ligand L, while the tetrahedral conformation of Ag center consists of two O and two N atoms. Infinite zigzag chains of Ag-tetrahedrals are formed. The hydrazinide L2− ligands of octahedral-V centers link adjacent chains to form an undulated heterometal based 2D layer. DFT calculations on 1 reproduced the geometric parameters and the electronic absorptions were predicted. The coordination polymer 1 showed very selective heterogeneous catalytic activity with 77–89% conversion in oxidation of alkenes, cyclooctane and benzyl alcohol by H2O2.

In this paper, (liquid + liquid) equilibrium (LLE) data for the ternary systems (cyclohexane, or cyclooctane, or methylcyclohexane + ethylbenzene + 1-ethyl-3-methylimidazolium ethylsulfate) have been determined experimentally at T = 298.15 K and atmospheric pressure. The solubility curves and the tie-line compositions of the conjugate phases were obtained by means of density. The degree of consistency of the tie-lines was tested using the Othmer–Tobias equation, and the Non-Random Two-Liquid (NRTL) and the Universal Quasi-Chemical (UNIQUAC) models were used to correlate the phase equilibrium in the systems. Selectivity and solute distribution ratio were evaluated for the immiscible region.

In this paper, the separation of toluene from cycloalkanes by liquid extraction using the ionic liquid 1-ethyl-3-methylimidazolium ethylsulfate, [EMim][ESO4], as solvent was studied. Liquid–liquid equilibrium (LLE) data for ternary systems {cyclohexane, or cyclooctane, or methylcyclohexane + toluene + [EMim][ESO4]} were determined at T = 298.15 K and atmospheric pressure. Selectivity and solute distribution ratio, derived from the tie-lines, were used to determine the ability of this ionic liquid as solvent for the separation of toluene from its mixtures with cycloalkanes. The degree of consistency of the tie-lines was tested using the Othmer–Tobias equation, and the experimental LLE data were correlated using the non-random two-liquid (NRTL) and the UNIversal QUAsi-Chemical (UNIQUAC) models.

Experimental densities are reported for n-pentane, n-octane, cyclooctane, 2,2,4-trimethylpentane, n-decane, and toluene to ∼280 MPa and ∼250 °C. These densities are in good agreement with available literature data that typically cover lower pressure and temperature ranges than those reported here. The data are modeled with the Peng–Robinson (PR) and Soave–Redlich–Kwong (SRK) cubic equations, the temperature-dependent, volume-translated SRK equation, the temperature- and density-dependent SRK equation, and the SAFT and PC-SAFT equations. Mean absolute percentage deviation (MAPD) values between densities calculated with the PR equation and literature data are 4.55 for n-pentane, 2.91 for n-octane, 3.68 for cyclooctane, 3.98 for 2,2,4-trimethylpentane, 5.58 for n-decane, and 1.99 for toluene. With the exception of 2,2,4-trimethylpentane, these MAPD values are substantially better than those obtained with the SRK and modified SRK equations. Although both SAFT-based models have MAPD values significantly lower than those with the PR equation, the PC-SAFT equation provides the lowest MAPD values.