67-63-0Relevant articles and documents
HOMOGENEOUS HYDROGENATION OF KETONES TO ALCOHOLS WITH RUTHENIUM COMPLEX CATALYSTS
Sanchez-Delgado, R.A.,Ochoa, O.L. De
, p. 427 - 434 (1980)
A number of ruthenium triphenylphosphine complexes catalyse the reduction of ketones to their corresponding alcohols in the presence of water.The most convenient catalyst precursors are carbonyl containing complexes which do not promote decarbonylation of the substrate.The hydrogenation of acetone with hydridochlorocarbonyltris(triphenylphosphine)ruthenium is first order with respect to the substrate concentration, the catalyst concentration, the hydrogen pressure and the water concentration.Turnover numbers up to 15,000 have been achieved with this catalyst.Other ketones are also reduced by RuHCl(CO)(PPh3)3 and the rate of the reaction is dependent on the nature of the substrate.
Improved (photo)catalytic propene hydration in a gas/solid system by using heteropolyacid/oxide composites: Electron paramagnetic resonance, acidity, and role of water
García-López, Elisa I.,Marcì, Giuseppe,Pomilla, Francesca R.,Liotta, Leonarda F.,Megna, Bartolomeo,Paganini, Maria C.,Gionco, Chiara,Giamello, Elio,Palmisano, Leonardo
, p. 1900 - 1907 (2017)
Binary materials composed of the oxides SiO2, TiO2 and N-doped TiO2 and the Keggin heteropolyacid (PW12) were prepared and physicochemically characterized. They were used as catalysts and photocatalysts for the hydration of propene to 2-propanol. The characterization of the samples, particularly the electron paramagnetic resonance (EPR) spectroscopy results and the acidity properties, were useful to explain the key role played by the PW12 in the composite materials in the thermal and photoassisted catalytic processes. The simultaneous pres-ence of heat and UV light improved the activity of PW12 in the thermal process, and the binary materials showed better (photo)catalytic activities than that of the bare PW12 in almost all cases. For the first time, this work evidenced through EPR spectroscopy that the increase of reactivity under irradiation could be attributed to the ability of photoexcited PW12 to trap electrons, particularly if the PW12 is supported. Moreover, the effect of water on the reactivity was also studied.
Rh-CeO2 Interaction induced by High-temperature Reduction. Characterization and Catalytic Behaviour in Transient and Continuous Conditions
Trovarelli, Alessandro,Dolcetti, Giuliano,Leitenburg, Carla de,Kaspar, Jan,Finetti, Paola,Santoni, Antonino
, p. 1311 - 1320 (1992)
The effects of the high-temperature reduction of Rh/CeO2 catalyst on the hydrogenation of CO, CO2, acetone and ethene, and on the hydrogenolysis of ethane, in transient and continuous conditions, have been investigated.The high-temperature reduction (HTR) at 773 K induced a transient Rh-CeO2 interaction in the catalyst which enhances the rate of CO, CO2 and acetone hydrogenation.Temperature-programmed reduction (TPR) and X-ray photoelectron spectroscopy (XPS) show the reduction of Ce4+ to Ce3+ after HTR in the near surface layers.We suggest that the oxygen vacancies on the support (i.e. presence of Ce3+) can interact with the CO moiety promoting its activation.
Kinetics of an Associative Ligand-Exchange Process: Alcohol Exchange with Arsenate(V) Triesters
Baer, Carl D.,Edwards, John O.,Kaus, Malcolm J.,Richmond, Thomas G.,Rieger, Philip H.
, p. 5793 - 5798 (1980)
The rate of alcohol exchange with trialkyl arsenates has been studied by three techniques.Exchange of the straight-chain alcohols (ethyl, n-propyl, n-butyl, and n-pentyl) was studied in acetonitrile solution by using proton NMR line broadening.Activation enthalpies and entropies were found in the ranges 1 to 6kJ mol-1 and -204 and -226 J mol-1 K-1, respectively.The reactions are subject to acid catalysis for which slightly higher ΔH and less negative ΔS values were found.Methyl exchange, studied by the same technique, is about one powere of ten faster.Isopropyl exchange, about three powers of ten slower, was studied in acetonitrile and dichloromethane solutions by deuterium labeling, using proton NMR.The interchange reaction of benzyl alcohol with triisopropyl arsenate in acetonitrile or dichloromethane was followed by spectrophotometry.Hydrogen bonding between alcohol and ester (which complicates order determination) was observed when reactants were at concentrations greater than about 10-2 M.The strongly associative mechanism is discussed.
The heme monooxygenase cytochrome P450cam can be engineered to oxidize ethane to ethanol
Xu, Feng,Bell, Stephen G.,Lednik, Jaka,Insley, Andrew,Rao, Zihe,Wong, Luet-Lok
, p. 4029 - 4032 (2005)
(Graph Presented) A NADH turnover rate of 741 min-1 in the oxidition of ethane to ethanol is observed with an engineered form of the heme monooxygenase cytochrome P450cam - the first example of such activity for a P450 enzyme (CC analysis shown). Ethanol is formed at 78 min-1 (10.5 % coupling). The mutant is ≈45 % high-spin in the absence of substrate, making it a useful platform for P450 structure-function studies.
Hydrodeoxygenation of glycerol into propanols over a Ni/WO3–TiO2 catalyst
Greish, Alexander A.,Finashina, Elena D.,Tkachenko, Olga P.,Nikul'shin, Pavel A.,Ershov, Mikhail A.,Kustov, Leonid M.
, p. 119 - 120 (2020)
Hydrodeoxygenation of glycerol in a flow reactor over a bifunctional Ni/WO3–TiO2 catalyst at 240–255 °C and hydrogen pressure of 3 MPa affords propan-1-ol and propan-2-ol in total yield of 94%.
TiO2/polymeric supported silver nanoparticles applied as superior nanocatalyst in reduction reactions
Sedghi, Roya,Asadi, Shima,Heidari, Bahareh,Heravi, Majid M.
, p. 65 - 73 (2017)
A novel polymeric nanocomposites (TiO2/poly(acrylamide-co-methylenbisacrylamide)) decorated with silver nanoparticles (Ag NPs) denoted as (Ag–TiO2/poly(AM-co-MBAM)) was prepared and fully characterized. Initially, the surface of TiO
Electrode Potential of a Dispersed Raney Nickel Electrode during Acetone Hydrogenation: Influence of the Solution and Reaction Kinetics
Pardillos-Guindet, J.,Vidal, S.,Court, J.,Fouilloux, P.
, p. 12 - 20 (1995)
The hydrogenation of acetone was investigated in basic aquueous solutions with undoped and chromium-doped catalysts.The reaction was carried out under pressure in an autoclave equipped with a reference electrode.The consumption of hydrogen and the electrode potential were measured during the course of the reaction.A mathematical model was applied which fits the experimental kinetic data well.It allows the computation of the rate constant and the absorption equilibrium constants.The kinetics obey a Langmuir-Hinshelwood mechanism with competitive adsorption.The metallic catalyst particles behave like a dispersed electrode and an electrochemical double layers is formed at their surface.In the presence of hydrogen alone, the metal potential obeys the Nernst law for the hydrogen electrode.During acetone hydrogenation, the double layer is modified and the measured potential goes to the positive region for several tens of millivolts, depending on whether the catalyst is doped or not.In all cases an experimental correlation was found between this experimental potential rise and the reaction rate.
CATALYTIC AND STOICHIOMETRIC REDUCTION OF KETONES AND ALDEHYDES BY THE HYDRIDOTETRACARBONYL FERRATE ANION
Marko, Laszlo,Radhi, Mazin A.,Otvos, Irma
, p. 369 - 376 (1981)
Acetone is catalytically reduced to isopropyl alcohol by carbon monoxide and water in the presence of iron carbonyls and triethylamine at 100 deg C and 100 bar.Use of NaOH in place of triethylamine gives a much less efficient catalyst system.The Et3NH*HFe(CO)4 system also catalyses the reduction of n-butyraldehyde to n-butyl alcohol at room temperature in a fast stoichiometric reaction, whereas NaHFe(CO)4 is inactive under the same conditions.The Et3NH+ cation is necessary for the transfer of a proton to the carbonyl group, while the HFe(CO)4- anion carries out nucleophilic attack on carbonyl group and supplies the hydride ion.
Synthesis, Characterization, Stability and Cytotoxic Evaluation of Novel Titanium(IV) Complexes of 8-Hydroxyquinoline and 2-Hydroxy-N-phenylbenzylamine Derivatives
Samuel, Blassan,Pathak, Madhvesh
, p. 683 - 689 (2020)
A new class of moisture stable heteroleptic titanium(IV) complexes, synthesized from 8-hydroxyquinoline of the type [(Q)2Ti(2-O-5-XC6H3CH2NC6H4R] (3a-j), was prepared by reacting the antecedent molecule [(Q2)Ti(OiPr)2] (2) with various 2-hydroxy-N-phenyl-benzylamine analogues in 1:1 molar ratios in dry toluene (where, HQ = 8-hydroxyquinoline; iPr = isopropyl; R = H, 4-CH3, 4-OCH3, 2-Cl, 4-Cl, 2-Br, 4-Br; X= H, Br). Moisture sensitive study disclosed that these new metal complexes were unreacted for 72 h. Mass spectral data were employed for proving the mono-nuclearity of the new derivatives. Thermal decomposition pattern of the new derivatives was explained by thermogravimetric analyses. Elemental analyses data are in concordance with their expected values. The hexa-coordinated way of titanium-ligand linkage is further proved through NMR, FTIR, and UV-visible spectral studies. The cytotoxic efficiency of new complexes was tested against MDA-MB-231 human breast carcinoma cell line. Complex 3a exhibited the highest cytotoxic potential of 0.039 μM in comparison to all its analogues of this series by employing cisplatin as the standard.
