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The given text is a scientific research article that provides detailed information about the synthesis and characterization of various chemical compounds. It includes measurements, physical properties, spectroscopic data, and reaction conditions for the compounds synthesized. The article is technical and specific to the field of chemistry, and may be useful for researchers studying organic chemistry and chemical synthesis. [Extracted from the article]

Two novel cyclohexane derivatives, [2,6-bis(4-chloro/bromophenyl)-4-hydroxy-4-(pyridin-2-yl)-cyclohexane-1,3-diyl]bis(pyridin-2-ylmethanones), were synthesized in one step from 2-acetylpyridine and 4-chloro- or 4-bromobenzaldehyde with high yield under mild conditions. The reaction sequence is likely to include the formation of chalcone, Cannizzaro reaction, and one-pot cyclization, and this process represents a new strategy in cyclization reactions. The synthesized compounds showed fluorescence in the region λ 320–450 nm, and their structure was confirmed by spectroscopic data, as well as by X-ray analysis. [ABSTRACT FROM AUTHOR]

A tandem intramolecular conjugate addition reaction was conducted with α,β-bisenones as selected Michael acceptors which were converted into 1,2,3-trisubstituted six-membered rings in the presence of activated sulfur nucleophiles. The products were obtained in good to excellent yields (maximum yield: 99%). Various substituted α,β-bisenones and sulfur nucleophiles were examined to understand the substrate scope of the reaction. Only one diastereomer was isolated, as lithium iodide mediated enolate trapping reactions improve the stereoselectivity of reactions involving 1,2,3-trisubstituted cyclohexanes. [ABSTRACT FROM AUTHOR]

Non-metal-catalyzed hydrogenation of arenes represents a sustainable and environment-friendly approach for the synthesis of cyclohexane derivatives. Herein, we report the development of a borenium-ion catalyst system which can hydrogenate a number of monocyclic arenes. Additionally, this metal-free catalytic system allows selective partial or full hydrogenation of naphthalene and anthracene by modification of the reaction conditions. Our mechanism studies suggest that the borenium-arene-mediated H2 splitting takes place before the rate-limiting step and the hydride transfer between the resulting neutral borane and protonated arene is likely the rate-limiting step in the catalytic process. [ABSTRACT FROM AUTHOR]

The current work describes the synthesis of new series of N‐(1‐(cyclohexylcarbamoyl) cyclohexyl)‐N‐phenylarylamides (10 a‐h) and 3‐cyclohexyl‐1,2‐diphenyl and 2‐(substituted phenyl)‐1,3‐diazaspiro[4.5]decanes (12 a‐h).The new compounds were screened for their anticonvulsant and antinociceptive activities using sodium valproate and tramadol hydrochloride, respectively as reference standards. 4‐Chloro‐N‐(1‐(cyclohexylcarbamoyl)cyclohexyl)‐N‐phenylbenzamide (10 b), 3‐Cyclohexyl‐1,2‐diphenyl‐1,3‐diazaspiro[4.5]decane (12 a) and 3‐Cyclohexyl‐1‐phenyl‐2‐(3,4,5‐trimethoxyphenyl)‐1,3‐diazaspiro[4.5]decane (12 d) showed higher anticonvulsant activity than sodium valproate at dose 0.08 mmol/kg. On the other hand, 4‐Amino‐N‐(1‐(cyclohexylcarbamoyl) cyclohexyl)‐N‐phenylbenzamide (10 h) and 3‐Cyclohexyl‐1‐phenyl‐2‐(3,4,5‐trimethoxyphenyl)‐1,3‐diazaspiro[4.5]decane (12 d) exhibited higher antinociceptive potential in both intensity and duration than tramadol hydrochloride. The pharmacokinetics of the new compounds were calculated in‐ silico. Additionally, 3D pharmacophoric model was generated. Compounds N‐(1‐(cyclohexylcarbamoyl)cyclohexyl)‐N‐phenyl benzamide (10 b) and 3‐Cyclohexyl‐1,2‐diphenyl‐1,3‐diazaspiro[4.5]decane (12 a) showed a higher anticonvulsant activity compared to sodium valproate. 4‐Amino‐N‐(1‐(cyclohexyl carbamoyl)cyclohexyl)‐N‐phenylbenzamide (10 h) had a higher antinociceptive potential in both intensity and duration compared to tramadol hydrochloride. [ABSTRACT FROM AUTHOR]

The thermochemical network of 300 isodesmic reactions was used to simultaneously adjust the enthalpies of formation for 25 adamantanes. The experimental enthalpies of formation of these compounds were treated as unknowns in the least-squares minimization of deviations between the theoretically predicted enthalpies of reaction and experimental values. The theoretical enthalpies of reactions were obtained using Gaussian-4 (G4) method. A result of a least-squares fit confirms the accuracy of experimental enthalpies of formation of 15 adamantanes, whereas the experimental measurements for 10 adamantanes require re-examination. [ABSTRACT FROM AUTHOR]

Proper decision making in multifacitated situation is very challenging task. It is especially difficult if there are many alternatives and criteria that are often contradictory. Analytical chemistry and related sciences involve many situations where decisions on complex problems are made. The support tools may be the use of MCDA (Multi-criteria Decision Analysis) algorithms. They formalize the decision process, make it transparent in all its aspects. In this review the application of MCDA methods in analytical and some related sciences is presented. The main areas of utilization are selection of proper materials and selection or optimization of processes. Their potential areas of applications are far from being fully explored. This review provides useful insights into the MCDA methods usage in analytical chemistry field that can stimulate the application of these tools in complex decision making processes. [ABSTRACT FROM AUTHOR]

We investigated the metamizole metabolite 4-formylaminoantipyrine (4-FAA) by 1 H dynamic nuclear magnetic resonance. 4-FAA exhibits a carbon-nitrogen partial double bond that rotates slowly enough, on a resonance time scale, to provide the simultaneous spectra of two rotamers. We examined various solvents in an attempt to understand how protic and aprotic environments influence the anti and syn rotamer equilibriums. Moreover, we compared experimental data and theoretical calculations to evaluate the thermodynamic parameters of the rotational process. [ABSTRACT FROM AUTHOR]

The functional structure and the design of a CVD reactor for the synthesis of vertically oriented carbon nanotube (VOCNT) arrays on silicon substrates are described. To synthesize VOCNTs, various organic compounds, viz., toluene, cyclohexane, and acetonitrile, and their mixtures in the liquid state were tested under normal conditions. [ABSTRACT FROM AUTHOR]

The CoMo hollow bimetallic oxide has been exploited in the aerobic epoxidation of cyclohexene containing labile allylic hydrogen atoms using ethylbenzene as a solvent. Cooperativity between Co(II) and Mo(VI) sites consisting of Co O Mo or Mo−O δ− ⋯Co δ+ unit on hollow oxide surfaces is investigated for controlling preferred epoxidation catalysis via tandem oxygen transfer. Various characterization techniques like XRD diffraction, N 2 physisorption, TEM, and Raman, XPS, Infrared, and UV–vis spectroscopies are employed to reveal the relationship between structure of active sites and catalytic performance. Together with these comprehensive experimental and computational studies, in this unique tandem catalytic process, Co(II) sites effectively mediate the first step of the overall oxidation cycle yielding a phenylethylperoxy radical by oxygen activation [Co(II) to Co(III) O 2 − to phenylethyl radical and finally to a phenylethylperoxy radical]. On the other hand, Mo(VI) sites are shown to be the excellent catalytic species for the subsequent epoxidation step by the transfer of oxygen atom of the phenylethylperoxy radical to cyclohexene. Hence, a 59% epoxidation selectivity with 33% cyclohexene conversion is accomplished through the required combination of Co(II) and Mo(VI) (2:1), allowing to tune epoxidation efficiency toward higher driving forces (relative to oxygenation of allylic hydrogen atom). This remarkably different catalytic performances between Co(II) and Mo(VI) can be attributed to the stronger overall polarization ability of Mo(VI) toward σ* O O orbital of the O O unit derived from its d-type orbitals, which helps the donor-acceptor interactions with the double bond. [ABSTRACT FROM AUTHOR]

The reaction of chiral cis-[(1S,2S)-dch]Pt(NO3)2 (M) [where (1S,2S)-dch = (1S,2S)-1,2-diaminocyclohexane] with a hexadentate ligand (L) in 3 : 1 stoichiometric ratio yielded a [12+4] self-assembled chiral M12L4 molecular tetrahedron (T). The cage T features an internal 3D nanocavity with large open ‘windows’, enabling it to catalyze Michael addition reactions of a series of nitrostyrene derivatives with indole in a 9 : 1 water : methanol mixture. [ABSTRACT FROM AUTHOR]

Two new cobalt(II) complexes with the formulas of [Co(3-ebpba)(Hcppa)]n (1) and [Co(3-bpcd)(Hcppa)]n (2) have been obtained under the solvothermal conditions by reacting of two semi-rigid bis(pyridyl)-bis(amide) ligands with different spacers [3-ebpba = (E)-4,4′-(ethene-1,2-diyl)bis(N-pyridin-3-yl)benzamide, 3-bpcd = N,N′-bis(pyridin-3-yl)cyclohexane-1,4-dicarboxamide] and the aromatic tricarboxylic acid [H3cppa = 5-(4-carboxyl-phenoxy)-isophthalic acid]. Complex 1 represents a 2D polymeric layer constructed by the 1D [Co(Hcppa)]n ‘chinese knot’-shaped chains and µ2-bridging 3-ebpba ligands. Complex 2 is a 1D ribbon chain based on the 1D [Co(Hcppa)]n ‘comb’-liked chains and the bidentate 3-bpcd ligands. Finally, the adjacent 2D layers or 1D chains are extended to 3D supramolecular networks via hydrogen-bonding interactions for the title complexes. In addition, the electrochemical behaviors, fluorescent properties and the photocatalytic activities of two cobalt(II) complexes towards the degradation of organic dyes have been studied. [ABSTRACT FROM AUTHOR]

Two cobalt complexes, cis -[Co II (MPCA)Cl 2 ] ( C1 ) and cis -[Co II (MPCA)Br 2 ] ( C2 ) (MPCA = N, N ’-dimethyl- N, N ’-bis(2-pyridinylmethyl)cyclohexane-1,2-diamine), were synthesized as catalysts for visible light induced photocatalytic CO 2 reduction. The two complexes adopt cis -octahedral coordination geometry with different halogen ligands at cis -coordination sites, which were characterized by X-ray crystal analysis. The two cobalt catalysts exhibited different activity on catalysing CO 2 -to-CO conversion in the presence of Ir(ppy) 3 as photosensitizer and triethylamine as sacrificial electron donor in DMF under visible light irradiation. The rate of CO production of C2 -system was faster than that of C1 -system in the initial stage of irradiation. However, the better stability of C1 -system than that of C2 -system leading a total TON CO of 470 from C1 -system compared with of 403 from C2 -system were obtained after 48 h of irradiation. Mechanism studies revealed that the photoinduced electron transfer from Ir(ppy) 3 * to cobalt complex, C1 or C2 , operates to generate active Co I species for CO 2 binding. The C2 -system possesses larger rate constant and driven force of the photoinduced electron transfer process than those of in C1 -system. [ABSTRACT FROM AUTHOR]

Abstract: In our effort towards measuring the parity violation energy difference between two enantiomers, a simple chiral oxorhenium complex 5 bearing enantiopure 2‐mercaptocyclohexan‐1‐ol has been prepared as a potential candidate species. Vibrational circular dichroism revealed a chiral environment surrounding the rhenium atom, even though the rhenium is not a stereogenic center itself, and enabled to assign the (1S,2S)‐(−) and (1R,2R)‐(+) absolute configuration for 5. For both compound 5 and complex 4, previously studied by us and bearing a propane‐2‐olato‐3‐thiolato ligand, relativistic calculations predict parity violating vibrational frequency differences of a few hundreds of millihertz, above the expected sensitivity attainable by a molecular beam Ramsey interferometer that we are constructing. [ABSTRACT FROM AUTHOR]

Shuttle-shaped, porous copper oxide (CuO) microparticles were prepared from Cu(OH)2 in a water/cyclohexane interfacial reaction followed by heat treatments at different temperatures. The CuO catalysts produced high catalytic activity and good durability for hydrazine oxidation reaction (HOR). Among all catalysts, CuO catalyst heat treated at 200°C provided the highest HOR activity with an onset potential of -0.204 V and a high oxidation peak current density of 0.87 mA cm-2 of HOR. HOR performances of the CuO catalysts correlated to their porous structure and transition of different Cu species. These findings shed light on factors influencing HOR activity of CuO catalysts. [ABSTRACT FROM AUTHOR]

Synthesis of HDC by methoxycarbonylation of HDA with DMC was carried out over the bulk and hybrid heteropoly acid (HPA) catalyst. The catalysts were systematically characterized by XRD, FTIR, SEM and NH-TPD techniques. The by-products produced in the reaction were identified and a possible reaction pathway was proposed based on the by-products analysis. The performances of bulk and hybrid HPA catalysts were evaluated. The H[SiWO] catalyst revealed high performance compared with other catalysts and its high performance was attributed to its acidic properties. Effects of reaction parameters and reusability of the H[SiWO] catalyst were also investigated. Under the optimized reaction conditions, HDA conversion reached 93.2% with 64.8% HDC selectivity and only 3.8% by-product selectivity. Moreover, a possible reaction mechanism was proposed for the synthesis of HDC over H[SiWO] catalyst. [ABSTRACT FROM AUTHOR]

This paper presents a self-consistent model of electrohydrodynamic (EHD) laminar plumes produced by electron injection from ultra-sharp needle tips in cyclohexane. Since the density of electrons injected into the liquid is well described by the Fowler-Nordheim field emission theory, the injection law is not assumed. Furthermore, the generation of electrons in cyclohexane and their conversion into negative ions is included in the analysis. Detailed steady-state characteristics of EHD plumes under weak injection and space-charge limited injection are studied. It is found that the plume characteristics far from both electrodes and under weak injection can be accurately described with an asymptotic simplified solution proposed by Vazquez et al. ["Dynamics of electrohydrodynamic laminar plumes: Scaling analysis and integral model," Phys. Fluids 12, 2809 (2000)] when the correct longitudinal electric field distribution and liquid velocity radial profile are used as input. However, this asymptotic solution deviates from the self-consistently calculated plume parameters under space-charge limited injection since it neglects the radial variations of the electric field produced by a high-density charged core. In addition, no significant differences in the model estimates of the plume are found when the simulations are obtained either with the finite element method or with a diffusion-free particle method. It is shown that the model also enables the calculation of the current-voltage characteristic of EHD laminar plumes produced by electron field emission, with good agreement with measured values reported in the literature. [ABSTRACT FROM AUTHOR]

By using chiral auxiliaries and hydrogen bonding interactions, we have developed diastereoselective photocycloaddition of 2-naphthalenecarboxylates and 2,3-naphthalenedicarboxylates with furan derivatives. In photoreactions of ( ℓ )-menthyl 2-naphthalenecarboxylate with furan and 3-furanmethanol, respective maximum 48% and 40% diastereomeric excesses (d.e.) are observed. In photoreactions of di-8-phenyl-( ℓ )-menthyl 2,3-naphthalenedicarboxylate with 3-furanmethanol, maximum 67% d.e. is obtained. Use of solvents of low polarity, low temperatures and low furan concentration leads to increased diastereoselectivities. Variable-temperature (VT) NMR and fluorescence quenching studies indicate that hydrogen bonding interactions between the carbonyl oxygen of naphthalenecarboxylic acid esters and the OH group in 3-furanmethanol take place in both the ground and excited states. The results of computational studies show that geometries of C 2 symmetric naphthalenedicarboxylate reactants are important in governing the high diastereoselectivity in the photoreactions of 2,3-naphthalenedicarboxylates. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrodeoxygenation is a versatile strategy to produce jet fuel range hydrocarbons from biomass. • Different catalytic systems for the HDO of lignin-derived phenolics to cyclohexane are discussed. • Advancements in efficient catalysts towards the synthesis of renewable cyclohexane are displayed. • Catalytic HDO reaction mechanism of phenolics involving highly effective catalysts is elaborated in detail. • Provision of the perspectives and opportunities for future research in this field. The over-reliance on the fossil energy requires the exploitation of sustainable biomass feedstock for supporting the fuel and chemical supply in modern society. Cyclohexane is an exceedingly important precursor for the manufacture of polymers, chemicals and biofuels. In view of the growing demand for cyclohexane and the unsustainability of traditional petroleum-based production processes, continuous effort has been invested in the synthesis of cyclohexane from greener and abundant biomass resources. This review systematacially pays attention to the recent achievements in catalysts for the hydrodeoxygenation conversion of lignin-derived phenolics into cyclohexane. In the meantime, the characteristics of novel catalysts and reaction mechanisms involved also are further summarized and discussed with the purpose of providing a perspective for the design and development of the highly active catalysts. Finally, some personal suggestions for improving the existing challenges and potential opportunities within this promising field are displayed in order to inspire widespread scientists committed to a low-carbon society to make biomass resources play a key role in fuel and chemical production. [ABSTRACT FROM AUTHOR]

Toluene dioxygenase-catalysed cis-dihydroxylations of substituted aniline and phenol substrates, with a Pseudomonas putida UV4 mutant strain and an Escherichia coli pCL-4t recombinant strain, yielded identical arene cis-dihydrodiols, which were isolated as the preferred cyclohex-2-en-1-one cis-diol tautomers. These cis-diol metabolites were predicted by preliminary molecular docking studies, of anilines and phenols, at the active site of toluene dioxygenase. Further biotransformations of cyclohex-2-en-1-one cis-diol and hydroquinone metabolites, using Pseudomonas putida UV4 whole cells, were found to yield 4-hydroxycyclohex-2-en-1-ones as a new type of phenol bioproduct. Multistep pathways, involving ene reductase- and carbonyl reductase-catalysed reactions, were proposed to account for the production of 4-hydroxycyclohex-2-en-1-one metabolites. Evidence for the phenol hydrate tautomers of 4-hydroxycyclohex-2-en-1-one metabolites was shown by formation of the corresponding trimethylsilyl ether derivatives. [ABSTRACT FROM AUTHOR]

A series of Ni-Cu supported on SBA-15 were prepared by impregnation, and used as catalysts in cyclohexane dehydrogenation for hydrogen production. The results indicated that the addition of Cu into Ni changes the crystal structure of metal Ni, and forms Ni-Cu alloy. Thus, Cu improves the reduction properties of Ni. Conversely, Ni stables and disperses metal Cu. With the space limitation of the ordered channels and high surface area of SBA-15, the bimetallic Ni-Cu/SBA-15 catalysts expose large amounts of selective active sites composed uniformly with Ni and Cu. Therefore, they present not only excellent catalytic performance for cyclohexane dehydrogenation, but also low coke formation. The in-situ DRIFT studies have shown the vinyl species, indicating the existence of alkenes in the reactive intermediates. Additionally, the strong absorption of benzene on the metal could induce benzene was dehydrogenated further to carbon. [ABSTRACT FROM AUTHOR]

Porous magnesium oxide as the adsorbent of phosphate was prepared by hexamethylene tetramine (HMT) assisted hydrothermal method. Various techniques were used to carefully characterize crystallinity structure, morphology, pore structure, and adsorption performance of the prepared MgO samples. The results show that the HMT plays a key role during the formation of pore structure of MgO materials. The BET surface area and pore size were varied as a function of the feeding ratio of HMT and Mg 2+ in the synthesis system. When the ratio is equal to 1.2, the obtained MgO sample has the appropriate BET surface area of 181.02 m 2 g −1 and the averaged pore diameter of ca. 10.76 nm, which shows the highest adsorption capacity of 236 mg g −1 among the prepared samples and the outstanding adsorption performance compared with those reported in the literature. The adsorption of these porous MgO materials matches well the pseudo second order kinetic model and the Freundlich isotherms. Besides, the phosphate anions was adsorbed on MgO to produce magnesium hydrogen phosphate and magnesium phosphate. [ABSTRACT FROM AUTHOR]

Synthesis and characterization of 15N-labeled and partially 13C-labeled oxaliplatin in a racemic mixture with its S,S enantiomer, (SP-4-2)-[(trans-1R,2R/1S,2S-15N2)-cyclohexane-1,2-diamine][(13C2)oxalato]platinum(II), is presented. 15N labeling of trans-cyclohexane-1,2-diamine (DACH) was conducted by reacting cyclohexane-1,2-dione with the 15N source (15N)hydroxylamine hydrochloride. After reduction, trans-(15N2)DACH was isolated as a tartrate salt and reacted with K2[PtCl4]. Subsequent reaction with (13C2)oxalate afforded the final 15N- and 13C-labeled oxaliplatin together with its S,S analog. Detailed characterization was performed by one- and twodimensional ¹H, 13C, 15N, and 195Pt NMR spectroscopy; highresolution mass spectrometry; and elemental analysis. The reaction behavior towards chloride ions, 5'-guanosine monophosphate, and L-methionine was studied by 1D ¹H, 13C, and 195Pt NMR spectroscopy and 2D [¹H,15N] and [¹H,195Pt] NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Two N,N'-bis(3-alkoxy-2-hydroxybenzyl)cyclohexane-1,2-diamine proligands, H2L¹ (R=OCH3) and H2L² (R=OC2H5), and five heterodinuclear ZnII/LnIII complexes, [Zn(L)(m-CH3COO)Ln(NO3)2], containing [L¹]2-and Gd3+, Tb3+, Er3+, or Yb3+ and [L2]2- and Yb3+ have been synthesised and structurally characterised. The complexes are isostructural and crystallise in the P21/n monoclinic space group. Zinc(II) is coordinated by the inner N2O2 donor set of the ligand and an oxygen of the bridging acetate anion; the lanthanide(III) ions possess an O9 coordination environment involving the interaction with the ligand's outer O4 donor set, two bidentate nitrate ions, and the bridging acetate. [ABSTRACT FROM AUTHOR]

We previously reported the design of spirooxindoles with two identical substituents at the carbon-2 of the pyrrolidine core as potent MDM2 inhibitors. In this paper we describe an extensive structure-activity relationship study of this class of MDM2 inhibitors, which led to the discovery of 60 (AA-115/APG-115). Compound 60 has a very high affinity to MDM2 (Ki < 1 nM), potent cellular activity, and an excellent oral pharmacokinetic profile. Compound 60 is capable of achieving complete and long-lasting tumor regression in vivo and is currently in phase I clinical trials for cancer treatment. [ABSTRACT FROM AUTHOR]

The linkage of two P2-phosphazenyl groups through a C2-symmetric ( R, R)-1,2-diaminocyclohexane (DACH) backbone yielded the new chiral superbases DACH-P2NMe2 and DACH-P2Pyr (Pyr=pyrrolidinyl). These bases were prepared by a Kirsanov reaction and studied with respect to their spectroscopic and structural characteristics. Theoretical calculations concerning their basicity properties revealed remarkable p KBH+ values of 38.1 and 39.9 on the acetonitrile scale; this makes them the strongest nonionic chiral superbases known to date. [ABSTRACT FROM AUTHOR]

A novel palladium-catalyzed aerobic (1+2) annulation was developed for the synthesis of 3-azabicyclo[3.1.0]hex-2-ene. The palladation of Csp3–H bonds took place twice at the same position in the whole reaction process. Preliminary mechanistic studies by in situ IR revealed that the second C–H palladation and reductive elimination might be slow steps. [ABSTRACT FROM AUTHOR]

Enantioselective tandem Michael-aldol and oxidative Michael-aldol approaches have been achieved for the formation of diversely substituted cyclohexanes in total regio-, diastereo- and enantioselective fashion. The presence of nitro, hydroxy and keto groups in the product provides a wide scope for further structural transformations. Furthermore, the utility of the catalytic process is demonstrated in the context of enantioselective formal synthesis of ABT-341, a DPP4 inhibitor. [ABSTRACT FROM AUTHOR]

By synthesizing derivatives of a trans-1,2-diaminocyclohexane precursor, three new functionalized porous organic cages were prepared with different chemical functionalities on the cage periphery. The introduction of twelve methyl groups ( CC16) resulted in frustration of the cage packing mode, which more than doubled the surface area compared to the parent cage, CC3. The analogous installation of twelve hydroxyl groups provided an imine cage ( CC17) that combines permanent porosity with the potential for post-synthetic modification of the cage exterior. Finally, the incorporation of bulky dihydroethanoanthracene groups was found to direct self-assembly towards the formation of a larger [8+12] cage, rather than the expected [4+6], cage molecule ( CC18). However, CC18 was found to be non-porous, most likely due to cage collapse upon desolvation. [ABSTRACT FROM AUTHOR]

A series of poly(ether-ester)s containing cardo cyclohexane moiety in the main chain was synthesized from 1,1-bis (4-(3-hydroxypropyloxy)phenyl) cyclohexane (BPPZ) and aliphatic and aromatic acid chlorides. The diol monomer, BPPZ, was synthesized from 1,1-bis (4-hydroxyphenyl) cyclohexane (BPZ) and 3-bromo-1-propanol. The solubility of the polymers was tested in various solvents. The intrinsic viscosity of the synthesized polymers was determined by Oswald viscometer and found to be 0.33-0.48 g/dl. The molecular structures of the monomer and polymers were confirmed by Fourier transform InfraRed, H-NMR and C-NMR spectral analyses. The thermal properties were studied with thermogravimetric analyses and differential scanning calorimetry. The thermogravimetric analyses data revealed that the polymers were stable up to 190 °C, and start degrading thereafter. The solubility and thermal stability of the synthesized polymer is enhanced due to the introduction of methylene spacer with ether group into the polymer chain backbone. The self-extinguishing property of the synthesized polymers was studied by the determination of limiting oxygen index values with Van Krevelen's equation. [ABSTRACT FROM AUTHOR]

The copper(ii) metal–organic framework (MOF) [Cu(η-1κN,N′,N′′:2κO,O′-L)(NO3)]n (1) [L = 4-((4-([2,2′:6′,2′′-terpyridin]-4′-yl)benzyl)oxy)benzoate] has been synthesized from a flexible bifunctionalised terpyridine species (HL). It was characterized by elemental, FT-IR, powder and single crystal X-ray diffraction analyses. Single crystal X-ray crystallography of 1 shows a 1D polymeric architecture, whose topological analysis illustrates a uninodal (2)-connected net having topological type 2C1. 1 shows good catalytic activity and selectivity towards the hydrocarboxylation of cyclohexane to cyclohexanecarboxylic acid in water/acetonitrile or water/ionic liquid [BMPyr][NTf2] [BMPyr = 1-butyl-1 methylpyrrolidinium; NTf2 = bis(trifluoromethanesulfonyl)imide] medium. It can be recycled and reused without any significant loss of catalytic efficiency. This study provides the first example of an efficient alkane hydrocarboxylation to carboxylic acid, in an ionic liquid and under mild conditions. [ABSTRACT FROM AUTHOR]

A new route for the synthesis of 2-alkanoyl(aryloyl)-5,5-dimethylcyclohexane-1,3-diones as cyclic β-triketones is described. This synthesis was conducted by the reaction of dimedone with cyanogen bromide and triethylamine to form first the intermediate salt, followed by the addition of various aliphatic and aromatic aldehydes. The structures of the products were characterized by IR, 1H, and 13C NMR spectroscopic techniques. A reaction mechanism is proposed. [ABSTRACT FROM AUTHOR]

7,20-Diisocyanoadociane (DICA) is a potent antimalarial isocyanoterpene endowed with a fascinating tetracyclic structure composed of fused chair cyclohexanes. We report a highly stereocontrolled synthesis of a late-stage intermediate, the 'Corey dione', from which DICA has been made previously. This formal synthesis features a rapid buildup of much of the complexity of the target through a sequence of enone tandem vicinal difunctionalization, Friedel-Crafts cyclodehydration, and sequential stereocontrolled reductions. Most importantly, this success establishes the broader feasibility of our previously developed general synthesis approach to the isocyanoterpene family and provides a blueprint for a very direct synthesis of DICA and related natural products. [ABSTRACT FROM AUTHOR]

Fe-, Ni-, and alloyed FeNi-filled carbon nanotubes (Fe@CNT, Ni@CNT, and FeNi@CNT) were prepared by a general strategy using a mixture of xylene and dichlorobenzene as carbon source, and ferrocene, nickelocene, and their mixture as catalysts. By tailoring the composition of the carbon precursor, the filling ratio and the wall thickness of metal@CNT could be controlled. For the catalytic oxidation of cyclohexane in liquid phase with molecular oxygen as oxidant, the highest activity was obtained over Fe@CNT synthesized from pure dichlorobenzene. However, Ni filling did not improve the activity of CNTs. The effects of metal filling, wall thickness, and defects on catalytic activity were investigated to determine the structure-activity relationship of the filled CNTs. The enhanced catalytic performance can be attributed to a combined contribution of thin walls of CNTs and confined electron-donating metals, which are favourable to electron transfer on the surfaces of CNTs. The modification of the electronic structure of CNTs upon Fe and Ni fillers insertion was elucidated through density functional theory calculations. [ABSTRACT FROM AUTHOR]

An "on water" hydroquinine-based primary amine-benzoic acid organocatalyst system was found to be best suited to produce 3,4,5-trisubstituted cyclohexanones with a nitro group in the 4-position from enones and nitro dienes under ambient conditions in good yield, with good diastereoselectivity, and with excellent enantioselectivity. An appreciable rate enhancement by water was observed compared to organic solvents. Mechanistic analysis of the reaction suggests that it followed an endo [4 + 2] cycloaddition with enamine of enone as diene and nitro diene as dienophile. [ABSTRACT FROM AUTHOR]

BACKGROUND Due to environmental concerns, there is a need to eliminate or drastically reduce the use of conventional organic solvents, as these are environmentally harmful. This paper reports on a novel one-pot synthesis of tetrabromoethylcyclohexane ( TBECH) in aqueous medium, using amino-functionalized ionic liquids, which catalyze the reaction and make it more environmentally friendly. RESULTS Compared with the traditional synthesis, tetrabromoethylcyclohexane is obtained with equivalent yield (90%), at room temperature, in a short reaction time (∼2 h compared with the previous 17 h) and with a strong reduction of the use of organic solvents; finally two isomers are obtained instead of four. Furthermore, a novel procedure to prepare the ionic liquids has been designed and two new ones have also been synthesised. The calculated environmental factors ( EFs), which measure the environmental sustainability, showed a strong reduction of the use of organic solvents for all syntheses of ionic liquids and TBECHs. CONCLUSIONS The excellent properties of amino-functionalized ionic liquids as solvents and catalysts for chemo- and diastereo-selective bromination of C  C bonds in water were confirmed with the synthesis of tetrabromoethylcyclohexane. Given the wide use of brominated compounds in the chemical industry, this procedure could be of wide interest. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A cationic Pd(II)-catalyzed cascade cyclization reaction of alkyne-tethered carbonyl compounds was developed. This reaction is initiated by intramolecular oxypalladation of alkynes with an ester group followed by 1,2-addition of the formed C-Pd(II) bond to the carbonyl group, providing a highly efficient method for the synthesis of cyclohexane-fused isocoumarins. [ABSTRACT FROM AUTHOR]

Developing an economic and efficient approach for the production of adipic acid is a grand challenge in the chemical industry. Toward this goal, we report a simple method for selective synthesis of adipic acid from cyclohexane with NO2 by using Ni-Al-VPO/MCM-41 as catalyst. The physical-chemical properties of supported Ni-Al-VPO/MCM-4 catalysts were characterized, the reaction conditions were optimized, and the reusability of the catalyst was examined. The results showed that the supported 30%Ni-Al-VPO/MCM-41 catalyst exhibited excellent catalytic performance with 65.1% of cyclohexane conversion and 85.3% of selectivity toward adipic acid, especially, its catalytic performance was still stable after five runs. Maybe this developed method has potential industrial application prospects for production of adipic acid. [ABSTRACT FROM AUTHOR]

The non-heme iron halogenases CytC3 and SyrB2 catalyze C--H bond halogenation in the biosynthesis of some natural products via S = 2 oxoiron(lV)-- halide intermediates. These oxidants abstract a hydrogen atom from a substrate C--H bond to generate an alkyl radical that reacts with the bound halide to form a C-X bond chemoselectively. The origin of this selectivity has been explored in biological systems but has not yet been investigated with synthetic models. Here we report the characterization of S = 2 [FeIV(0)(TQA)(Cl/Br)]+ (TQA = tris(quinolyl-2-methyl)amine) complexes that can preferentially halogenate cyclohexane. These are the first synthetic oxoiron(IV)--halide complexes that serve as spectroscopic and functional models for the halogenase intermediates. Interestingly, the nascent substrate radicals generated by these synthetic complexes are not as shortlived as those obtained from heme-based oxidants and can be intercepted by O2 to prevent halogenation, supporting an emerging notion that rapid rebound may not necessarily occur in non-heme oxoiron(IV) oxidations. [ABSTRACT FROM AUTHOR]

We demonstrate VPO composites as efficient catalysts for highly selective oxidation of cyclohexane to adipic acid with NO2. In particular, the Ni–Al–VPO composite catalyst exhibits the striking conversion of cyclohexane (60.6%) and exceptionally high selectivity towards adipic acid (85.0%). Moreover, N2O is an environmentally harmful gas, and its yield in the present process is only 0.03 t/t adipic acid, which is far below that obtained using the industrial method (0.3 t/t adipic acid). This work provides a new strategy for the one-step synthesis of dicarboxylic acids from cycloalkanes. [ABSTRACT FROM AUTHOR]

Multiple molecular wires braided together in a single assembly, termed as molecular cable, are promising next-generation materials for effective long-range charge transport. As an example of the platform for constructing molecular cables, 1,3,5-trifluorenylcyclohexane (TFC) and its difluorenyl analogues (DFCs) were systematically investigated both experimentally (X-ray crystallography) and theoretically (DFT calculations). Although the syntheses of DFCs were successfully achieved, the synthesis of TFC, which involved a similar intramolecular Friedel-Crafts cyclization as the last step, was unsuccessful. An exhaustive study of the conformational landscape of cyclohexane ring of TFC and DFCs revealed that TFC is a moderately strained molecule (~17 kcal/mol), and computational studies of the reaction profile show that this steric strain, present in the transition state, is responsible for the unusually high (~5 years) reaction half-life. A successful synthesis of TFC will require that the steric strain is introduced in multiple steps, and such alternative strategies are being currently explored. [ABSTRACT FROM AUTHOR]

Enantiomerically pure bicyclic derivatives of 2-azanorbornane containing sulfonamide, amide, and thiourea functionalities were synthesized using aza-Diels-Alder reaction. [ABSTRACT FROM PUBLISHER]

Extremophile archaeal organisms overcome problems of membrane permeability by producing lipids with structural elements that putatively improve membrane integrity compared to lipids from other life forms. Herein, we describe a series of lipids that mimic some key structural features of archaeal lipids, such as: 1) single tethering of lipid tails to create fully transmembrane tetraether lipids and 2) the incorporation of small rings into these tethered segments. We found that membranes formed from pure tetraether lipids leaked small ions at a rate that was about two orders of magnitude slower than common bilayer-forming lipids. Incorporation of cyclopentane rings into the tetraether lipids did not affect membrane leakage, whereas a cyclohexane ring reduced leakage by an additional 40 %. These results show that mimicking certain structural features of natural archaeal lipids results in improved membrane integrity, which may help overcome limitations of many current lipid-based technologies. [ABSTRACT FROM AUTHOR]

Organocatalytic asymmetric domino reactions of γ-nitro ketones and enones have been developed for the construction of functionalized cyclohexane skeletons with four stereogenic carbon atoms, including one tetrasubstituted carbon stereocenter. 5-Nitropentan-2-one and 6-nitrohexan-3-one reacted with chalcone to afford six-membered carbocycles with four consecutive stereocenters in yields of 51-91 % with 81-93 % ee and >20:1 dr. In addition, 4-nitro-1-phenylbutan-1-one reacted with 4-arylbut-3-en-2-ones to afford six-membered carbocycles with two double consecutive stereocenters in yields of 59-92 % with 89-94 % ee and >20:1 dr. Interestingly, both four consecutive and nonconsecutive stereocenters could be constructed by these substrate-controlled domino reactions. [ABSTRACT FROM AUTHOR]

The hydrodeoxygenation of various phenols to form cyclohexanes was achieved at 110 °C under an H2 atmosphere at ambient pressure using a Pt/H-ZSM-5 catalyst and octane as the solvent. [ABSTRACT FROM AUTHOR]

A concise, economical, and highly enantioselective synthesis of bismesylate intermediate of lurasidone HCl, an antipsychotic, has been developed. The key steps involved in the synthesis are thionyl chloride–catalyzed esterification of tetrahydrophthalic anhydride in MeOH, epimerization ofcistotransisomer, hydrolysis of the diester, resolution of the diacid, reduction with Red-Al, and finally bismesylation of the corresponding diol, which provided the desired intermediate ((1 R,2 R)-cyclohexane-1,2-diyl)bis(methylene) dimethanesulfonate in overall good yield. [ABSTRACT FROM PUBLISHER]

The novel catalysts xMg–2.3Cu/SBA-15 with copper and magnesium oxide co-supported on mesoporous silica were synthesized by an impregnation method. The newly synthesized catalysts were characterized using a series of techniques such as BET, XRD, H2-TPR, UV-vis, XPS, EDS and TEM. The catalytic performance was evaluated by using selective oxidation of cyclohexane with molecular oxygen as the oxidant in a solvent free system. The incorporation of magnesium improved the dispersion of copper oxide and prevented the deep oxidation of cyclohexanol and cyclohexanone. The selectivity of K/A oil was up to 99.3% with 12% conversion of cyclohexane over the 1.2Mg–2.3Cu/SBA-15 catalyst. To our knowledge, this is the best result for the heterogeneous oxidation of cyclohexane by O2. [ABSTRACT FROM AUTHOR]

Estimation of ring strain energies (RSEs) of substituted cyclohexanes c-C6HxR12–x (R = F, Cl, Me; x = 0, 2, 4, 8, 10, 12) using homodesmotic reaction methods gives implausible results for highly substituted cases, particularly, c-C6R12. Prior work suggests that this stems from poorly canceled interactions between substituents on the acyclic reference molecules. We apply here our semi-homodesmotic approach that minimizes use of acyclic references and ensures cancellation of intramolecular substituent interactions. The approach provides RSEs that are more consistent with chemical intuition, although they are higher than expected for “strain-free” cyclohexanes. The RSE for c-C6Me12 is predicted to be 11.9 kcal mol–1. RSEs for halogenated rings rise significantly from 8–9 kcal mol–1 for c-1,1,2,2-C6H8R4 to 44–50 kcal mol–1 for c-C6R12 (R = F, Cl). The increase, and accompanying observation of larger RSEs for “adjacent CR2” systems, can be tied to increased bond distances in the rings upon progressive substitution. The sizable RSE for perchlorocyclohexane suggests that it may be susceptible to ring-opening reactions, a facet of its chemistry that is currently unexplored. [ABSTRACT FROM AUTHOR]