Showing papers on "Cyclohexanone published in 2018"
TL;DR: The first example of direct formal cross-coupling of diaryl ether 4-O-5 linkage models with amines is reported, in which dual C(Ar)-O bond cleavages form valuable nitrogen-containing derivatives.
Abstract: Lignin is the second most abundant organic matter on Earth, and is an underutilized renewable source for valuable aromatic chemicals. For future sustainable production of aromatic compounds, it is highly desirable to convert lignin into value-added platform chemicals instead of using fossil-based resources. Lignins are aromatic polymers linked by three types of ether bonds (α-O-4, β-O-4, and 4-O-5 linkages) and other C-C bonds. Among the ether bonds, the bond dissociation energy of the 4-O-5 linkage is the highest and the most challenging to cleave. To date, 4-O-5 ether linkage model compounds have been cleaved to obtain phenol, cyclohexane, cyclohexanone, and cyclohexanol. The first example of direct formal cross-coupling of diaryl ether 4-O-5 linkage models with amines is reported, in which dual C(Ar)-O bond cleavages form valuable nitrogen-containing derivatives.
98 citations
TL;DR: In this paper, a novel catalyst of molybdenum supported on Ti-pillared interlayer clay (Ti-PILC) was successfully prepared which performed well in oxidative desulfurization (ODS) with cyclohexanone peroxide (CYHPO) as oxidant under mild conditions.
87 citations
TL;DR: In this article, the performance of Pd supported on SiO 2 and Nb 2 O 5 for the HDO of phenol reaction at different temperatures using a fixed-bed reactor was investigated.
80 citations
TL;DR: The photo-electrochemical C-H bond activation ofcyclohexane to produce cyclohexanol and cyclo hexanone (KA oil) with high partial oxidation selectivity and high current utilization ratio was achieved in air at room temperature at atmospheric pressure.
Abstract: The photo-electrochemical C-H bond activation of cyclohexane to produce cyclohexanol and cyclohexanone (KA oil) with high partial oxidation selectivity (99 %) and high current utilization ratio (76 %) was achieved in air at room temperature at atmospheric pressure. The production rate of KA oil was accelerated by applying a bias. The incident photon to current efficiencies at 365 and 420 nm were 57 % and 24 %, respectively.
80 citations
TL;DR: DUT-67, an 8-connected zirconium and 2,5-thiophenedicarboxylate-based metal-organic framework (MOF), was postsynthetically functionalized by l-proline via solvent-assisted linker incorporation to obtain a chiral base catalyst to be a promising heterogeneous catalyst for the asymmetric Michael addition of cyclohexanone to trans-β-nitrostyrene.
Abstract: DUT-67, an 8-connected zirconium and 2,5-thiophenedicarboxylate-based metal–organic framework (MOF), was postsynthetically functionalized by l-proline via solvent-assisted linker incorporation to obtain a chiral base catalyst. The parent monocarboxylate could be almost completely exchanged by l-proline after 5 days of treatment. The resulting chiral DUT-67 was demonstrated to be a promising heterogeneous catalyst for the asymmetric Michael addition of cyclohexanone to trans-β-nitrostyrene with excellent yield (up to 96%) and enantioselectivity comparable to that of l-proline in homogeneous reaction (ee of approximately 38%). The Zr-MOF could be reused at least five times without substantial degradation in the crystallinity or catalytic activity. No leaching of catalytically active species into the liquid phase was detected over five cycles.
69 citations
TL;DR: In this paper, a zirconium-based organic-inorganic coordination polymer with magnetic property (MZCCP) was successfully prepared by the reaction of ZrCl4 and cyanuric acid (CA) on the surface of ferriferrous oxide (Fe3O4).
67 citations
TL;DR: In this article, the effect of the support on the performance of Pd-based catalysts for hydrodeoxygenation of different model molecules (phenol, m-cresol, anisole, guaiacol) in the vapor phase at 573
Abstract: This work addresses the effect of the support on the performance of Pd-based catalysts for hydrodeoxygenation of different model molecules (phenol, m-cresol, anisole, guaiacol) in the vapor phase at 573 K. The activity and the selectivity to deoxygenated products strongly depended on the support, regardless the model molecule. For HDO of phenol and m-cresol, benzene and toluene were the dominant products on niobia supported catalysts, whereas cyclohexanone and methylcyclohexanone were the main compounds formed on Pd/SiO2. For HDO of anisole, demethoxylation reaction producing benzene is favored over Pd/Nb2O5 catalyst, while demethylation is the preferred route over Pd/SiO2. Phenol and methanol were the main products observed for HDO of guaiacol over all catalysts but significant formation of benzene was detected over Pd/Nb2O5. The improved deoxygenation performance over the niobia supported catalysts is explained in terms of the oxophilic sites represented by Nb4+/Nb5+ cations. These catalysts were also tested for HDO of pine pyrolysis vapors. All three catalysts were effective for reducing the total yield of oxygenated products. The extent of deoxygenation was highest over the Pd/Nb2O5 and Pd/NbOPO4 catalysts. The effectiveness of Pd/Nb2O5 and Pd/NbOPO4 for deoxygenation of real feeds is in good agreement with the model compound results and suggests that these catalysts are promising materials for the upgrading of pyrolysis vapors to produce hydrocarbon fuels.
65 citations
TL;DR: In this paper, the effect of the addition of a second metal (Cu, Ag, Zn, Sn) on the performance of Pd/ZrO2 catalyst for HDO of phenol at 573 K in the gas phase was investigated.
Abstract: This work investigated the effect of the addition of a second metal (Cu, Ag, Zn, Sn) on the performance of Pd/ZrO2 catalyst for HDO of phenol at 573 K in the gas phase. The incorporation of dopants resulted in the formation of Pd–X (Cu, Ag, Zn) alloys, which reduced the reaction rate for HDO and increased the selectivity to hydrogenation products (cyclohexanone and cyclohexanol). For PdSn/ZrO2, alloying was also observed but tin oxide was still present on the surface after reduction at 773 K. For Pd/ZrO2 and PdSn/ZrO2, the oxophilic sites represented by Zr and Sn cations promotes the hydrogenation of the carbonyl group of the keto-tautomer intermediate formed, producing benzene as the main product. All catalysts significantly deactivated during the reaction but the deactivation degree depended on the type of the metal. Pd/ZrO2 and PdZn/ZrO2 and PdAg/ZrO2 exhibited approximately the same deactivation degree. However, the loss of activity was less pronounced for PdSn/ZrO2 catalyst. Pd dispersion significantly decreased during the reaction, indicating that the sintering of Pd particles is one of the causes for catalyst deactivation.
63 citations
TL;DR: In this article, a silica-supported rhodium catalyst for the selective hydrogenation of phenol to cyclohexanone under mild conditions has been developed, which is active at room temperature and 1 1/m H 2 pressure and can be easily activated by in-situ reduction.
57 citations
01 May 2018
TL;DR: In this article, the significances, strategies and mechanisms for the production of cyclohexanone are briefly described, and the evolution of phenol hydrogenation in gas/liquid phase by the classification of catalyst types is summarized.
Abstract: Selective hydrogenation of phenol to cyclohexanone has attracted a great deal of attentions both in industry and academic field. Here in this review, the significances, strategies and mechanisms for the production of cyclohexanone are briefly described. Then, we mainly summarize the evolution of phenol hydrogenation in gas/liquid phase by the classification of catalyst types. In situ hydrogenation techniques including catalytic transfer hydrogenation (CTH) and electro-catalytic hydrogenation (ECH) of phenol are also discussed. Despite technology of catalyst design has been developed rapidly within the past decades, the direct evidences to understand the reaction mechanisms and kinetics are still scarce. Therefore, it is still of great challenge to explore the function mechanisms and design advanced catalysts with high activity and high selectivity (>95%) for direct hydrogenation of phenol to cyclohexanone. This review may provide guidance for these attempts.
44 citations
TL;DR: Three non-chlorinated solvents were examined for extracting PHA produced by the bacterial strain Cupriavidus necator H16 cultivated on vegetable oil as a sole carbon source and cyclohexanone in particular was identified as an expedient candidate to efficiently drive novel, sustainable PHA extraction processes.
Abstract: An economically viable method to extract polyhydroxyalkanoates (PHAs) from cells is desirable for this biodegradable polymer of potential biomedical applications. In this work, two non-chlorinated solvents, cyclohexanone and γ-butyrolactone, were examined for extracting PHA produced by the bacterial strain Cupriavidus necator H16 cultivated on vegetable oil as a sole carbon source. The PHA produced was determined as a poly(3-hydroxybutyrate) (PHB) homopolyester. The extraction kinetics of the two solvents was determined using gel permeation chromatography (GPC). When cyclohexanone was used as the extraction solvent at 120 °C in 3 min, 95% of the PHB was recovered from the cells with a similar purity to that extracted using chloroform. With a decrease in temperature, the recovery yield decreased. At the same temperatures, the recovery yield of γ-butyrolactone was significantly lower. The effect of the two solvents on the quality of the extracted PHB was also examined using GPC and elemental analysis. The molar mass and dispersity of the obtained polymer were similar to that extracted using chloroform, while the nitrogen content of the PHB extracted using the two new solvents was slightly higher. In a nutshell, cyclohexanone in particular was identified as an expedient candidate to efficiently drive novel, sustainable PHA extraction processes.
TL;DR: A heterologous pathway comprising novel enzymes with compatible kinetics was designed in Pseudomonas taiwanensis VLB120 enabling in‐vivo cascade for synthesizing lactones from cycloalkanes, completely converted with a selectivity of 65% for ϵ‐caprolactone formation in 2 hr without accumulation of intermediate products.
Abstract: Chemical synthesis of lactones from cycloalkanes is a multi-step process challenged by limitations in reaction efficiency (conversion and yield), atom economy (by-products) and environmental performance. A heterologous pathway comprising novel enzymes with compatible kinetics was designed in Pseudomonas taiwanensis VLB120 enabling in-vivo cascade for synthesizing lactones from cycloalkanes. The respective pathway included cytochrome P450 monooxygenase (CHX), cyclohexanol dehydrogenase (CDH), and cyclohexanone monooxygenase (CHXON) from Acidovorax sp. CHX100. Resting (non-growing) cells of the recombinant host P. taiwanensis VLB120 converted cyclohexane, cyclohexanol, and cyclohexanone to ϵ-caprolactone at 22, 80-100, and 170 U gCDW-1 , respectively. Cyclohexane (5 mM) was completely converted with a selectivity of 65% for ϵ-caprolactone formation in 2 hr without accumulation of intermediate products. Promiscuity of the whole-cell biocatalyst gave access to analogous lactones from cyclooctane and cyclodecane. A total product concentration of 2.3 g L-1 and a total turnover number of 36,720 was achieved over 5 hr with a biocatalyst concentration of 6.8 gCDW L-1 .
TL;DR: In this article, the role of catalyst reduction method in the liquid-phase phenol hydrogenation to cyclohexanone over Pd@CN (N-doped porous carbon).
TL;DR: In this article, a solvent-free liquid-liquid-solid heterogeneous reaction was successfully implemented in a micro-reaction system containing two T-junction microreactors, and the effects of temperature, pressure, residence time, concentrations of reactants and catalyst on the reaction performance were systematically investigated.
TL;DR: Aldol condensation of the furfural species with cyclic ketones was catalyzed by NaOH and the target condensation intermediates were obtained in yields of more than 90% at room temperature (30 °C) with a short reaction time (40 min).
Abstract: Developing renewable long-chain cycloalkanes from lignocellulosic biomass is of significance because it offers huge resource storage, wide applications in aviation/diesel fuels and mitigation of CO2 emissions. In this paper, cycloalkanes with carbon chain lengths of 13–18 were produced from biomass-derived furfural species (furfural and 5-hydroxymethylfurfural) and cyclic ketones (cyclopentanone and cyclohexanone) via aldol condensation, followed by hydrogenation to saturate the CC and CO bonds, and hydrodeoxygenation to remove oxygen atoms. The aldol condensation of the furfural species with cyclic ketones was catalyzed by NaOH and the target condensation intermediates were obtained in yields of more than 90% at room temperature (30 °C) with a short reaction time (40 min). By using amorphous zirconium phosphate combined with Pd/C as the catalyst, liquid cycloalkanes were produced at the optimal conditions with a yield of 76%. When the combined solid catalyst was reused, the target products reduced after the second run but the initial yield could be largely recovered by recalcination of the spent zirconium phosphate. Considering that cyclopentanone and cyclohexanone can be easily produced from furfural (originating from hemicellulose) and phenol (originating from lignin), respectively, this condensation has the potential to achieve the integrated conversion of biomass-derived cellulose, hemicellulose and lignin to jet fuel and/or diesel additives.
TL;DR: In this paper, the authors derived Abraham solvation parameter model correlations for describing the partitioning and solubility behavior of organic nonelectrolyte solutes and inorganic gases in both anhydrous butanone and cyclohexanone solvents.
Abstract: Updated Abraham solvation parameter model correlations are derived for describing the partitioning and solubility behaviour of organic nonelectrolyte solutes and inorganic gases in both anhydrous butanone and cyclohexanone solvents. The butanone and cyclohexanone correlations are based on data sets that contain 103 and 72 experimental data points, respectively. The derived correlations for butanone describe the experimental partitioning and solubility behaviour to within a standard deviation of 0.145 log units. A slightly smaller standard deviation of 0.135 was observed between the experimental and back-calculated values for the cyclohexanone solvent correlation equations.
TL;DR: In this paper, a new two-step process was developed for the synthesis of high-density jet fuel range tricyclic alkanes with methyl benzaldehydes and cyclohexanone which can be derived from lignocellulose.
TL;DR: This review describes recent research progress concerning catalytic dehydrogenative aromatization and I2 promoted oxidative aromatized reactions in view of the types of cyclohexanone and cyclo hexenone substrates and reactions, including the associated mechanisms and developments.
Abstract: Phenols and phenol derivatives serve as synthetic building blocks for the construction of compounds ranging from polymers to pharmaceuticals. Despite numerous methods for phenol synthesis, the catalytic dehydrogenation of carbocyclic compounds such as cyclohexanones and cyclohexenones to generate substituted phenol derivatives has received much attention. This review describes recent research progress concerning catalytic dehydrogenative aromatization and I2 promoted oxidative aromatization reactions in view of the types of cyclohexanone and cyclohexenone substrates and reactions, including the associated mechanisms and developments.
TL;DR: In this paper, amorphous copper-chromium catalysts with different Cu/Cr molar ratios have been prepared by a sol-gel method and were used in the oxidation of cyclohexane to KA-oil.
TL;DR: In this article, a series of new materials were prepared by applying one-step synthesis procedure based on sol-gel technique, which contained 1.5% of cobalt ions and 5% of metal oxide in the TUD-1 mesoporous material.
Abstract: M-Co-TUD-1; a series of the new materials was prepared by applying one-step synthesis procedure based on sol-gel technique. The prepared materials contain 1wt% of cobalt ions and 5wt% of metal oxide (metal = Cr, Cu, Ti, Mn, Bi, V, or Sr) in the TUD-1 mesoporous material. The prepared materials were characterized by using XRD, DRS UV–vis, N2 sorption measurements, ICP elemental analysis, SEM, and HR-TEM. Characterization results showed that all the prepared materials contain isolated Co2+ ions and nanoparticles of Cr2O3, TiO2, MnO, V2O5 or bulky crystals of Bi2O3 and CuO incorporated in the silica matrix. The catalytic performance of the prepared materials was evaluated in liquid phase, free-solvent selective oxidation of cyclohexane to cyclohexanone and cyclohexanol by using TBHP as an oxidant at 70 °C. The prepared materials exhibited higher activity than either Co-TUD-1 or other M-TUD-1. More importantly, a very small concentration of the intermediate; cyclohexyl hydroperoxide (CHHP) was detected. In case of stability, Mn-Co-TUD-1 and Ti-Co-TUD-1 exhibited an excellent stability during the reaction. Moreover, Mn-Co-TUD-1 was successfully recycled up to 4 runs.
TL;DR: In this paper, an organically functionalized β-isomer of Anderson polyoxometalates (POMs) nanocluster with single-atom Mn, β-{[H3NC(CH2O)3]2MnMo6O18}− (1), was reported as a highly active catalyst to selectively catalyze the oxidation of cyclohexanone or KA oil with atom economy use of 30% H2O2 for the ecofriendly synthesis of adipic acid.
Abstract: Adipic acid is an important raw chemical for the commercial production of polyamides and polyesters. The traditional industrial adipic acid production utilizes nitric acid to oxidize KA oil (mixtures of cyclohexanone and cyclohexanol), leading to the emission of N2O and thus causing ozone depletion, global warming, and acid rain. Herein, we reported an organically functionalized β-isomer of Anderson polyoxometalates (POMs) nanocluster with single-atom Mn, β-{[H3NC(CH2O)3]2MnMo6O18}− (1), as a highly active catalyst to selectively catalyze the oxidation of cyclohexanone, cyclohexanol, or KA oil with atom economy use of 30% H2O2 for the eco-friendly synthesis of adipic acid. The catalyst has been characterized by single crystal and powder XRD, XPS, ESI-MS, FT-IR, and NMR. A cyclohexanone (cyclohexanol) conversion of >99.9% with an adipic acid selectivity of ~97.1% (~85.3%) could be achieved over catalyst 1 with high turnover frequency of 2427.5 h−1 (2132.5 h−1). It has been demonstrated that the existence of Mn3+ atom active site in catalyst 1 and the special butterfly-shaped topology of POMs both play vital roles in the enhancement of catalytic activity.
TL;DR: In this paper, the preferential solvation (PS) model was used to correlate solvent polarity and showed that local compositions of 1:1 (HBD-HBA) complex molecules were highly asymmetric.
Abstract: Kamlet–Taft (KT) parameters were measured for four nonaqueous hydrogen bond donor (HBD)–hydrogen bond acceptor (HBA) solvent-pair mixtures: methanol–cyclopentanone, methanol–cyclohexanone, ethanol–cyclopentanone, and ethanol–cyclohexanone to define their solvent polarity as a function of composition. KT mixed-solvent polarities differed greatly from molar average property values. The preferential solvation (PS) model was used to correlate solvent polarity and showed that local compositions of 1:1 (HBD–HBA) complex molecules were highly asymmetric. Trends of KT parameters of both cyclohexanone and cyclopentanone mixtures were similar, although the specific hydrogen bonding interactions of HBD–HBA complex molecules in cyclohexanone mixtures were stronger than those of cyclopentanone mixtures according to density functional theory calculations, infrared spectroscopy, and solution macroscopic properties. Application of the PS model to pharmaceuticals showed that the solvent-pair mixtures have wide-working com...
TL;DR: In this paper, the selectivity of phenol hydrogenation over Pd/C was successfully tuned by various Bronsted acid and base additives, and the basic condition witnessed decreased catalytic activity and cyclohexanone selectivity while the opposite trend was observed under acidic condition.
TL;DR: In this article, a facile one-pot synthesis method using 3-mercapto(propyl)trimethoxysilane (MPTMS) to anchor metal NPs to the support was presented.
13 Aug 2018
TL;DR: Phenol and cyclohexenone can interconvert by controlled palladium-catalyzed hydrogenation or oxidation, allowing N-functionalization of amines, and phenol is successfully used to N-cyclohexylate α-amino acids and small peptides in excellent yields under bio-compatible conditions without racemization.
Abstract: The functionalization of α-amino acids and peptides provides the opportunity to tailor the properties of these biomolecules for diverse applications in chemistry and biology. Previous methods for N-modification involve the use of aliphatic alcohols, aldehydes, or halides. Alternatively, phenolic compounds are more desirable alkylating reagents as they constitute the backbone of lignin, making them an attractive bio-renewable resource. Here we report a method to N-modify 17 out of the 20 amino acids with phenol or derivatives, with water as the sole by-product. N-arylation is achieved using 2-cyclohexen-1-one and cyclohexanone as the coupling partners. Notably, phenol is successfully used to N-cyclohexylate α-amino acids and small peptides in excellent yields under bio-compatible conditions without racemization. Phenol and cyclohexenone can interconvert by controlled palladium-catalyzed hydrogenation or oxidation, allowing N-functionalization of amines. Here this is applied to amino acids and small peptides, allowing a range of challenging substrates to be N-arylated using cyclohexenone or N-alkylated using phenol.
TL;DR: In this paper, aldol condensation of furfural and cyclohexanone in the presence of Mg•Al hydrotalcite-derived materials as solid basic catalysts at reaction temperatures from 25 to 90 °C and a cycloenanone-to-furfural molar ratio of 1−10.
Abstract: This study presents results on aldol condensation of furfural and cyclohexanone in presence of Mg‐Al hydrotalcite‐derived materials as solid basic catalysts at reaction temperatures from 25 to 90 °C and a cyclohexanone to furfural molar ratio of 1–10. Mg‐Al mixed oxide exhibited reasonable activity with furfural conversion of ca. 50 % after 180 min of the reaction at T=90 °C. The activity of reconstructed hydrotalcite was much higher with furfural conversion close to 100 % at short reaction times. In comparison with Mg‐Al mixed oxide, the initial reaction rate has increased 30–50 times. Under similar reaction conditions, cyclohexanone self‐condensation on HTC‐derived catalysts could not compete with aldol condensation because the former reaction was inhibited by produced water. The change in CH/F molar ratio influenced both furfural conversion and product selectivity; higher furfural content in the reaction mixture favored the second condensation step.
TL;DR: The utility of vanadium-catalyzed reactions to synthesize (+)-bi-2-hydroxy-3-carbazole in three steps from cyclohexanone and commercially available aniline derivatives is demonstrated.
TL;DR: In this paper, the behavior of cyclohexanone + 1-alkanol was studied as a function of composition and within a temperature range of 293.15 −323.15 K.
Abstract: In this article the behavior of cyclohexanone + 1-alkanol, namely, 1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 1-nonanol, and 1-decanol, binary mixtures through the density and viscosity measurements has been studied as a function of composition and within the temperature range of 293.15–323.15 K. The excess molar volume and viscosity deviations have been calculated and fitted by the Redlich–Kister polynomial equation. For binary mixtures of cyclohexanone + 1-pentanol, values of excess molar volume are negative and for other mixtures are positive. For all binary systems viscosity deviations are negative and increase with the alkyl chain of alcohol. The results provide information on the interactions among the molecules in the pure state as well as the binary liquid mixtures. The measured densities and viscosities have been applied to test the applicability of the PC-SAFT and free volume models.
TL;DR: Its catalytic performance towards the solvent-free microwave-assisted peroxidative oxidation of aliphatic and aromatic hydrocarbons under mild conditions is compared with that of dinuclear Cu(II) complexes of the same ligand, previously reported as antiproliferative agents.
Abstract: One-dimensional (1D) polynuclear Cu(II) complex (1) derived from (5-bromo-2-hydroxybenzylidene)-2-hydroxybenzohydrazide (H2L) is synthesized and characterized by elemental analysis, IR spectroscopy, ESI-MS, and single crystal X-ray crystallography. Its catalytic performance towards the solvent-free microwave-assisted peroxidative oxidation of aliphatic and aromatic hydrocarbons under mild conditions is compared with that of dinuclear Cu(II) complexes (2 and 3) of the same ligand, previously reported as antiproliferative agents. Polymer 1 exhibits the highest activity, either for the oxidation of cyclohexane (leading to overall yields, based on the alkane, of up to 39% of cyclohexanol and cyclohexanone) or towards the oxidation of toluene (selectively affording benzaldehyde up to a 44% yield), after 2 or 2.5 h of irradiation at 80 or 50 °C, respectively.
TL;DR: In this article, a simple and environmentally benign approach for highly selective preparation of e-caprolactone by oxidation of cyclohexanone has been carried out, which employed metal-free mesoporous silica nanorods as catalyst under atmospheric pressure.
Abstract: The development of efficient and environmentally friendly catalysts for oxidative reaction is of great importance in applied catalysis. In this work, a simple and environmentally benign approach for highly selective preparation of e-caprolactone by oxidation of cyclohexanone has been carried out, which employed metal-free mesoporous silica (mSiO2) nanorods as catalyst under atmospheric pressure. The metal-free silica catalyst was applied for the first time in the Baeyer–Villiger (B–V) oxidation reaction. It showed efficient catalytic performance for the B–V oxidation of various cyclic ketones and aliphatic ketones with O2/benzaldehyde as oxidant. The catalyst could be easily separated from the reaction system by filtration and reused several times without significance loss of activity. Moreover, electron paramagnetic resonance (EPR) spectra of the reaction were obtained, indicating the existence of benzoyloxyl radical. The mechanism study of the reaction demonstrated that the super large surface area dilu...