- Lubricant base oil for power transmission
-
An object of the present invention is to provide a lubricant base oil for power transmission (in particular, a lubricant base oil for traction drives) having a high traction coefficient and a high flash point. The present invention relates to a lubricant base oil for power transmission comprising an alicyclic dicarboxylic acid diester compound represented by general formula (1): wherein R1 to R5 are the same or different, and each represents hydrogen or linear or branched C1-4 alkyl, and two R1, two R2, two R3, two R4, and two R5 may respectively be the same or different; and ring A is wherein R represents C1-3 alkyl, and n represents 0, 1, or 2; when n represents 2, R may be the same or different.
- -
-
Page/Page column 26
(2021/03/17)
-
- Iridium-Catalyzed Domino Hydroformylation/Hydrogenation of Olefins to Alcohols: Synergy of Two Ligands
-
A novel one-pot iridium-catalyzed domino hydroxymethylation of olefins, which relies on using two different ligands at the same time, is reported. DFT computation reveals different activities for the individual hydroformylation and hydrogenation steps in the presence of mono- and bidentate ligands. Whereas bidentate ligands have higher hydrogenation activity, monodentate ligands show higher hydroformylation activity. Accordingly, a catalyst system is introduced that uses dual ligands in the whole domino process. Control experiments show that the overall selectivity is kinetically controlled. Both computation and experiment explain the function of the two optimized ligands during the domino process.
- Beller, Matthias,Huang, Weiheng,Jackstell, Ralf,Jiao, Haijun,Tian, Xinxin
-
supporting information
(2022/01/13)
-
- MOF-derived hcp-Co nanoparticles encapsulated in ultrathin graphene for carboxylic acids hydrogenation to alcohols
-
Highly efficient conversion of carboxylic acids to valuable alcohols is a great challenge for easily corroded non-noble metal catalysts. Here, a series of few-layer graphene encapsulated metastable hexagonal closed-packed (hcp) Co nanoparticles were fabricated by reductive pyrolysis of metal-organic framework precursor. The sample pyrolyzed at 400 °C (hcp-Co@G400) presented outstanding performance and stability for converting a variety of functional carboxylic acids and its turnover frequency was one magnitude higher than that of conventional facc-centered cubic (fcc) Co catalysts. In situ DRIFTS spectroscopy of model reaction acetic acid hydrogenation and DFT calculation results confirm that carboxylic acid initially undergoes dehydroxylation to RCH2CO* followed by consecutive hydrogenation to RCH2CH2OH through RCH2COH*. Acetic acid prefers to vertically adsorb at hcp-Co (0 0 2) facet with a much lower adsorption energy than parallel adsorption at fcc-Co (1 1 1) surface, which plays a key role in decreasing the activation barrier of the rate-determining step of acetic acid dehydroxylation.
- Dong, Mei,Fan, Weibin,Gao, Xiaoqing,Zhu, Shanhui
-
p. 201 - 211
(2021/06/03)
-
- Re/AC catalysts for selective hydrogenation of dimethyl 1, 4-cyclohexanedicarboxylate to 1, 4-cyclohexanedimethanol: Essential roles of metal dispersion and chemical environment
-
Rhenium, although viewed as one of the noble metals with lower-price, has been commonly used as doping element in the bimetallic catalysts due to its middlebrow to activate hydrogen. Its major role as catalyst is less frequently mentioned. In this work, rhenium has been decorated on the surface of activated carbon and used for the selective hydrogenation of dimethyl 1, 4-cyclohexanedicarboxylate (DMCD) to 1, 4-cyclohexanedimethanol (CHDM). Characterizations suggested that ReOx particles were anchored occupying the surface oxygenated groups on pre-functionalized carbon. Rhenium decoration modified both the textural and chemical properties of the samples. Electrons were easily transferred from Re to the neighboring C atoms as a result of the formation of fine ReOx particles. Medium strong acid sites were generated and rhenium species in the reduced states could be still maintained under appropriate rhenium dispersion. The moderate hydrogenation ability of rhenium catalyst partially restrained the excessive hydrogenation of CHDM to other by-products. Rational decoration of 5 wt% Re performed the better catalytic performance with complete conversion of diester and 66 % yield of diol. The specific rate reached 9.5×102 mmolDMCD?gRe-1?h-1 at 220 °C under 10 MPa H2.
- Dong, Yanan,Liang, Changhai,Luo, Jingjie,Qu, Enhui,Zhou, Yixue
-
-
- Catalytic hydrogenation products of aromatic and aliphatic dicarboxylic acids
-
Hydrogenation of aromatic dicarboxylic acids gave 100 % selectivity to respective cyclohexane dicarboxylic acid with 5 % Pd/C catalyst. 5 % Ru/C catalyst was observed to give over hydrogenation products at 493 K and at lower temperature (453 K) the selectivity for cyclohexane dicarboxylic acids was increased. Hydrogenation of phthalic acid with Ru-Sn/Al2O3 catalyst was observed to give phthalide instead of 1,2-benzene dimethanol or 2-hydroxy methyl benzoic acid. Ru-Sn/Al2O3 catalyst selectively hydrogenated the carboxylic group of cyclohexane dicarboxylic acids to give cyclohexane dimethanol. Use of proper catalysts and reaction conditions resulted in desired products.
- Shinde, Sunil B.,Deshpande, Raj M.
-
p. 1137 - 1142
(2019/04/05)
-
- Synthesis of gasoline and jet fuel range cycloalkanes and aromatics from poly(ethylene terephthalate) waste
-
For the first time, gasoline and jet fuel range C7-C8 cycloalkanes and aromatics were selectively synthesized by the alcoholysis of poly(ethylene terephthalate) (PET) waste, followed by solvent-free hydrogenation and hydrodeoxygenation (HDO). It was found that methanol is highly reactive for the alcoholysis of PET waste. In the absence of any catalyst, a high yield of dimethyl terephthalate (97.3%) was achieved under mild conditions (473 K, 3.5 h). Dimethyl terephthalate exists as a solid and can be automatically separated from methanol with a decrease in temperature. Subsequently, dimethyl terephthalate was liquefied to dimethyl cyclohexane-1,4-dicarboxylate by hydrogenation over noble metal catalysts. Among the investigated catalysts, Pt/C exhibited the highest activity. Finally, the dimethyl cyclohexane-1,4-dicarboxylate as obtained was further hydrodeoxygenated to C7-C8 cycloalkanes and aromatics that can be used as gasoline or additives to improve the densities (or volumetric heat value) and sealabilities of current bio-jet fuels. Bimetallic Ru-Cu/SiO2 was found to be a promising HDO catalyst. According to the characterization results, the excellent HDO performance of Ru-Cu/SiO2 can be explained by the formation of smaller Ru-Cu alloy particles during the catalyst preparation. In real applications, dimethyl cyclohexane-1,4-dicarboxylate can also be simultaneously hydrodeoxygenated with biomass derived oxygenates to produce jet fuel with a suitable content of cycloalkanes and aromatics.
- Tang, Hao,Li, Ning,Li, Guangyi,Wang, Aiqin,Cong, Yu,Xu, Guoliang,Wang, Xiaodong,Zhang, Tao
-
supporting information
p. 2709 - 2719
(2019/06/03)
-
- The compound, composition, and display device
-
PROBLEM TO BE SOLVED: To provide a compound capable of elevating an upper limit temperature where a SmC (smectic-C) phase of a liquid crystal can exist, broadening a temperature width of the SmC phase or enlarging a tilt angle of the SmC phase, and to provide a liquid crystal composition comprising the compound and a display element including the liquid crystal composition.SOLUTION: [1] The compound is expressed by general formula (i) shown below. In general formula (i), R and R' each independently represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 9 carbon atoms; A1, A2 and A3 each independently represent a 1,4-phenylene group or a 2,3-difluoro-1,4-phenylene group; m represents an integer of 1 to 10; and Y represents a cyclohexylene group, a phenylene group, a bicyclooctylene group or a dialkylsilylene group.
- -
-
Paragraph 0145-0147
(2017/07/26)
-
- Conversion of bis(2-hydroxyethylene terephthalate) into 1,4-cyclohexanedimethanol by selective hydrogenation using RuPtSn/Al2O3
-
1,4-Cyclohexanedimethanol (CHDM) is a highly valued and widely used monomer in the polymer industry. Bis(2-hydroxyethylene terephthalate) (BHET), the product of glycolysis of waste PET, is an excellent raw material for the preparation of CHDM. Herein, a series of monometallic, bimetallic and trimetallic supported catalysts were prepared for the one-pot conversion of BHET into CHDM by the impregnation method and good performance was found over trimetallic RuPtSn/Al2O3 catalysts containing various active sites to catalyze the hydrogenation of the phenyl and carbonyl groups. The influences of various reaction parameters including temperature, pressure and time on the hydrogenation reaction were studied, and 100% conversion and 87.1% yield of CHDM were obtained with the trimetallic supported catalyst with Ru/Sn 1.5. Moreover, through the comparison between various methods for the preparation of CHDM, the conversion of BHET into CHDM by the one-pot method is considered one of the most competitive methods.
- Hou, Danfeng,Xin, Jiayu,Lu, Xingmei,Guo, Xiaonan,Dong, Huixian,Ren, Baozeng,Zhang, Suojiang
-
p. 48737 - 48744
(2016/06/09)
-
- Tuning the chemoselective hydrogenation of aromatic ketones, aromatic aldehydes and quinolines catalyzed by phosphine functionalized ionic liquid stabilized ruthenium nanoparticles
-
Ruthenium nanoparticles (Ru NPs) stabilized by phosphine-functionalized ionic liquids (PFILs) were synthesized in an imidazolium-based ionic liquid using H2 as a reductant. Characterization showed well-dispersed particles of about 2.2 nm (TEM) and confirmed the PFIL stabilization of the Ru NPs (NMR). The Ru NPs stabilized by PFILs exhibited excellent activity and switchable chemoselectivity in the heterogeneous selective hydrogenation of aromatic ketones, aromatic aldehydes and quinolines under mild conditions.
- Jiang, He-Yan,Zheng, Xu-Xu
-
p. 3728 - 3734
(2015/07/07)
-
- Surface synergistic effect in well-dispersed Cu/MgO catalysts for highly efficient vapor-phase hydrogenation of carbonyl compounds
-
The highly efficient vapor-phase selective hydrogenation of carbonyl compounds (e.g. furfural (FAL) and dimethyl 1,4-cyclohexane dicarboxylate (DMCD)) to corresponding alcohols was achieved excellently over well-dispersed MgO-supported copper catalysts (Cu/MgO), which were prepared by an alternative separate nucleation and aging step method. The characterization results revealed that the structure and catalytic performance of the as-formed Cu/MgO catalysts were profoundly affected by Cu loading. Especially, the results confirmed that the decrease in the Cu loading could lead to the improvement of metal dispersion and the formation of more surface strong Lewis basic sites. In the vapor-phase selective hydrogenation of FAL to furfuryl alcohol (FOL) and DMCD to 1,4-cyclohexane dimethanol (CHDM), two Cu/MgO catalysts with Cu loadings of 27.6 wt% and 70.9 wt% exhibited superior catalytic performance with higher conversions (>97.3%) and selectivities to alcohols (>96.0%) compared to the other supported ones. The high efficiency of the as-formed Cu/MgO catalysts was mainly attributed to the surface synergistic catalytic effect between the catalytically active metallic copper species and the Lewis basic sites, which held the key to the hydrogenation reaction related to the hydrogen dissociation and the activation of the carbonyl groups.
- Liu, Hanwen,Hu, Qi,Fan, Guoli,Yang, Lan,Li, Feng
-
p. 3960 - 3969
(2015/08/03)
-
- PROCESS FOR THE PREPARATION OF 1,4-CYCLOHEXANEDIMETHANOL
-
Disclosed is a process for the preparation of 1,4-cyclohexanedimethanol from terephthalic acid. Terephthalic acid is esterified with (4-methylcyclohexyl)methanol and the terephthalate ester hydrogenated to 1,4-cyclohexanedimethanol in a 2-stage process. The (4-methylcyclohexyl)methanol that is formed during the hydrogenation step is recycled to the esterification reaction. After removal of the (4- methylcyclohexyl)methanol from the crude hydrogenation product, the 1,4- cyclohexanedimethanol product can be recovered and purified by a phase separation and distillation.
- -
-
Paragraph 0102
(2013/03/26)
-
- Single-step conversion of dimethyl terephthalate into cyclohexanedimethanol with Ru5PtSn, a trimetallic nanoparticle catalyst
-
Highly active and selective: A supported Ru5PtSn nanoparticle cluster (the picture shows an axial projection of a tomogram), prepared from the carbonyl cluster [PtRu5(CO)15(μ-SnPh 2)(μ6-C)], is an excellent catalyst in the single-step hydrogenation of dimethyl terephthalate to cyclohexanedimethanol under mild conditions (100°C, 20 bar H2). (Figure Presented).
- Hungria, Ana B.,Raja, Robert,Adams, Richard D.,Captain, Burjor,Thomas, John Meurig,Midgley, Paul A.,Golovko, Vladimir,Johnson, Brian F. G.
-
p. 4782 - 4785
(2007/10/03)
-
- Experimental determination of the conformational free energies (A values) of fluorinated substituents in cyclohexane by dynamic 19F NMR spectroscopy. Part 2. Extension to fluoromethyl, difluoromethyl, pentafluoroethyl, trifluoromethylthio and trifluoromethoxy groups
-
The synthesis of monosubstituted and 1,4-substituted cyclohexanes bearing one of the title groups is described. The conformational analysis of these compounds was studied by 19F NMR spectroscopy at various temperatures. Chemical shifts for each conformer above the coalescence temperature were obtained by binomial regression from low temperature values, allowing the high precision determination of the equilibrium constants, and the corresponding thermodynamic parameters (ΔG°, ΔH°, ΔS°) of the fluorinated substituents. For A values (-ΔG°298K), the following averaged data were obtained: 1.59 (CFH2), 1.85 (CF2H), 2.67 (C2F5), 0.79 (OCF3) and 1.18 (SCF3) [in kcal mol-1]. the Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2006.
- Carcenac, Yvan,Tordeux, Marc,Wakselman, Claude,Diter, Patrick
-
p. 447 - 457
(2007/10/03)
-
- Single-step, highly active, and highly selective nanoparticle catalysts for the hydrogenation of key organic compounds
-
Pores for cluster catalysts: Nanoparticles of both Ru5Pt and Ru10Pt2, uniformly distributed along the inner walls of mesoporous silica, exhibit high catalytic performance in the single-step hydrogenation of dimethyl terephthalate (DMT, to 1,4-cyclohexanedimethanol (CHDM); see scheme), of benzoic acid (to cyclohexane carboxylic acid), and of naphthalene (in the presence of sulfur) to cisdecalin.
- Raja, Robert,Khimyak, Tetyana,Thomas, John Meurig,Hermans, Sophie,Johnson, Brian F. G.
-
p. 4638 - 4642
(2007/10/03)
-
- Alkane Functionalization on a Preparative Scale by Mercury-Photosensitized Cross-Dehydrodimerization
-
Alkanes can be functionalized with high conversions and in high chemical and quantum yields on a multigram scale by mercury-photosensitized reaction between an alkane and alcohols, ethers, or silanes to give homodimers and cross-dehydrodimers.The separation of the product mixtures is often particulary easy because of a great difference in polarity of the homodimers and cross-dimers.It is also possible to bias the product composition when the ratio of the components in the vapor phase is adjusted by altering the liquid composition.This is useful either to maximize chemical yield or to ease separation by favoring the formation of the most easily separated pair of compounds.The mechanistic basis of the reaction is discussed and a number of specific types of syntheses, for example of 2,2-disubstituted carbinols, are described in detail.The selectivity of cross-dimerization is shown to exceed that for homodimerization and reasons are discussed.Relative reactivities of different compounds and classes of compound are MeOHp-dioxanecyclohexane1,3,5-trioxacyclohexaneethanolisobutaneTHFEt3SiH.The observed selectivities generally parallel those for homodimerization, reported in the preceding paper, but certain differences are noted, and reasons for the differences are proposed.The bond-dissociation energy of Et3SiH is estimated from the reactivity data to be 90 kcal/mol.Eleven new carbinols are synthesized.
- Brown, Stephen H.,Crabtree, Robert H.
-
p. 2946 - 2953
(2007/10/02)
-
- Functionalization of Saturated Hydrocarbons. Part 4. The Gif System for Selective Oxidation using Molecular Oxygen
-
Various systems for the selective oxidation of saturated hydrocarbons have been developed.These are based on the idea of an iron catalyst which is reduced by electron transfer and oxidized by molecular oxygen simultaneously in the presence of a source of protons.Four modifications of this system (the Gif system) have been devised of which the best (Gif IV) consists of an iron catalyst with metallic zinc as the reductant, acetic acid as the proton source and pyridine as the solvent.At room temperature, using oxygen or air, saturated hydrocarbons are oxidized selectively to ketones in isolated yields superior to those reported for comparable model systems.
- Barton, Derek H. R.,Boivin, Jean,Gastiger, Michel,Morzycki, Jacek,Hay-Motherwell, Robyn S.,et al.
-
p. 947 - 956
(2007/10/02)
-
- Cycloalkylmethyl Radicals. Part 3. Dynamic Stereochemistry of Axial and Equatorial Cyclohexylmethyl and 4-Alkylcyclohexylmethyl Radicals
-
For cyclohexylmethyl and 4-alkylcyclohexylmethyl radicals the conformer in which the CH2. group adopts the axial position and that in which the CH2. group adopts the equatorial position can both be observed by e.s.r. spectroscopy.At 140 K the axial conformers have a(Hβ) ca. 42-43 G; the equatorial conformers have a(Hβ) ca. 30-31 G.For cis-4-methylcyclohexylmethyl radicals the ratio of the concentrations of the two conformers was studied as a function of temperature and shown to depend on the rate of radical ring inversion vs. the radical lifetime; the rate constant for ring inversion was obtained.As a check on the e.s.r. results the conformational equilibrium of cis-4-methylcyclohexylmethyl bromide was studied by 1H n.m.r. spectroscopy, which gave -ΔG0300(CH2Br) = 1.91 kcal mol-1.The relative conformer concentrations were also measured as a function of temperature for cyclohexylmethyl radicals and the conformational free energy difference of the CH2. group (-ΔG0300) was found to be 0.71 kcal mol-1.The preponderance of the conformer of the cis-4-methylcyclohexylmethyl radical with the CH3 group axial at T . group cannot because of its planarity.The barriers to rotation about the Cα-Cβ bonds in the axial radicals were found to be ca. 1.0 kcal mol-1 greater than those of the equatorial radicals; this is responsible for the greater a(Hβ) values of the axial radicals.The axial and equatorial conformers of cyclohexylmethyl radicals were investigated by semi-empirical SCF MO-methods.
- Ingold, Keith U.,Walton, John C.
-
p. 1337 - 1344
(2007/10/02)
-
- Conformational Preferences of some Substituted Methyl Groups in Cyclohexanes as Studied by Carbon-13 Nuclear Magnetic Resonance
-
Low temperature 13C NMR spectra of 80 : 20 mixtures of cis and trans-4-CH3-C6H10CH2X, where -C6H10- is 1,4-disubstituted cyclohexyl and X=Br, CN, OH, OCH3, Si(CH3)3, Sn(CH3)3, Pb(CH3)3 and HgOCOCH3 have been recorded.The signals of the trans (e, e) components were assigned from the ambient temperature spectra of C6H11CH2X and the established substituent effects of an equatorial methyl group in cyclohexane.Conformational equilibria of the cis (e, a a, e) components were then computed from the intensities of the (remaining) signals (ca. 180 K) of the two conformational isomers.From these equilibria A values of CH2X were calculated, assuming additivity of conformational energies of CH3 and CH2X (the counter-poise approach).In general, these values are very similar to the value of CH3, although some trends do emerge.This study provides α, β, γ and δ effects for a wide range of axial and equatorial -CH2X groups.
- Kitching, William,Olszowy, Henry,Adcock, William
-
p. 230 - 237
(2007/10/02)
-