496-10-6Relevant academic research and scientific papers
The solvent determines the product in the hydrogenation of aromatic ketones using unligated RhCl3as catalyst precursor
Bartling, Stephan,Chakrabortty, Soumyadeep,De Vries, Johannes G.,Kamer, Paul C. J.,Lund, Henrik,Müller, Bernd H.,Rockstroh, Nils
, p. 7608 - 7616 (2021/12/13)
Alkyl cyclohexanes were synthesized in high selectivity via a combined hydrogenation/hydrodeoxygenation of aromatic ketones using ligand-free RhCl3 as pre-catalyst in trifluoroethanol as solvent. The true catalyst consists of rhodium nanoparticles (Rh NPs), generated in situ during the reaction. A range of conjugated as well as non-conjugated aromatic ketones were directly hydrodeoxygenated to the corresponding saturated cyclohexane derivatives at relatively mild conditions. The solvent was found to be the determining factor to switch the selectivity of the ketone hydrogenation. Cyclohexyl alkyl-alcohols were the products using water as a solvent.
Fused-ring alkane fuel and photocatalytic preparation process thereof
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, (2020/07/05)
A process for preparing a fused-ring alkane fuel, wherein the fused-ring alkane fuel has the following structure: wherein n is 1 or 2; R1, R2, R3, R4 and R5 are H or —CH3 or —CH2CH3; the fused-ring alkane fuel has a density of greater than 0.870 g/cm3, a freezing point of not higher than ?50° C., and a net mass heat value of not less than 42.0 MJ/kg; the process for preparing a fused-ring alkane fuel, wherein the process includes steps of: (1) in a presence of ultraviolet light and a photocatalyst, a Diels-Alder cycloaddition reaction between a substituted or unsubstituted cyclic enone and a substituted or unsubstituted furan molecule occurs to produce a fuel precursor molecule: (2) the fuel precursor molecule obtained in the step (1) is subjected to hydrodeoxygenation to produce the fused-ring alkane fuel.
Oxygen-Deficient Tungsten Oxide as Versatile and Efficient Hydrogenation Catalyst
Song, Jiajia,Huang, Zhen-Feng,Pan, Lun,Zou, Ji-Jun,Zhang, Xiangwen,Wang, Li
, p. 6594 - 6599 (2015/11/18)
Heterogeneous hydrogenation is one of the most important industrial operations, and reduced metals (mostly noble metals and a few inexpensive metals) generally serve as the catalyst to activate molecular H2. Herein we report oxygen-deficient tungsten oxide, such as WO2.72, is a versatile and efficient catalyst for the hydrogenation of linear olefins, cyclic olefins, and aryl nitro groups, with obvious advantages compared with non-noble metal nickel catalyst from the aspect of activity and selectivity. Density functional theory calculations prove the oxygen-deficient surface activates H2 very easily in both kinetics and thermodynamics. Testing on several oxygen-deficient tungsten oxides shows a linear dependence between the hydrogenation activity and oxygen vacancy concentration. Tungsten is earth-abundant, and WO2.72 can be synthesized in large scale using a low-cost procedure, which provides an ideal catalyst for industrial application. Because oxygen vacancy is a common characteristic of many metal oxides, the findings in this work may be extended to other metal oxides and thus provide the possibility for exploring a new type of hydrogenation catalyst.
High temperature bromination Part XXIII: Bromination of octahydro-1H-indene and octahydro-1H-4,7-methanoindene
Ozer, Melek Sermin,Kilbas, Benan,Balci, Metin
, p. 388 - 404 (2014/01/23)
Thermal and photobromination of octahydro-1H-indene and octahydro-1H-4,7-methanoindene were investigated. Three isomeric tetrabromides (1,3,4,7-tetrabromo-2,3,4,5,6,7-hexahydro-1H-indene) were formed along with a smaller amount of tribromoindane and a pentabromide by thermal bromination of octahydro-1H-indene. The thermodynamically most stable isomers were formed. Morover, thermal and photochemical bromination of octahydro-1H-4,7-methanoindene furnished bromides resulting regiospecifically from the allylic bromination of the five-membered ring. Furthermore, the double bond formed as the intermediate functional group was also brominated due to its pyramidalization. The mechanism proposed for the formation of product distribution was discussed. ARKAT-USA, Inc.
Catalytic compositions and methods for asymmetric allylic alkylation
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, (2008/06/13)
Complexes of a selected class of chiral ligands with molybdenum, tungsten or chromium, preferably molybdenum, are effective as catalysts in highly enantioselective and regioselective alkylation of allylic substrates.
Catalytic compositions and methods for asymmetric allylic alkylation
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, (2008/06/13)
Complexes of a selected class of chiral ligands with molybdenum, tungsten or chromium, preferably molybdenum, are effective as catalysts in highly enantioselective and regioselective alkylation of allylic substrates.
Catalytic compositions and methods for asymmetric allylic alkylation
-
, (2008/06/13)
Complexes of a selected class of chiral ligands with molybdenum, tungsten or chromium, preferably molybdenum, are effective as catalysts in highly enantioselective and regioselective alkylation of allylic substrates. Such compositions provide a versatile and low-cost alternative to existing catalysts.
FORMATION OF SULPHUR COMPOUNDS IN THE HYDRODENITROGENATION OF 2-METHYLQUINOLINE, 2-METHYLPIPERIDINE, INDOLE, AND ISOQUINOLINE ON A NICKEL-TUNGSTEN CATALYST IN THE PRESENCE OF HYDROGEN SULPHIDE
Cerny, Mirko,Trka, Antonin
, p. 3413 - 3420 (2007/10/02)
2-Methylquinoline, 2-methylpiperidine, indole, and isoquinoline were subjected to hydrodenitrogenation (HDN) on a sulphidized nickel-tungsten catalyst in an autoclave at 300 and 350 deg C using pure hydrogen or a hydrogen-hydrogen sulphide mixture.The neutral fraction from the HDN of 2-methylquinoline and 2-methylpiperidine contained 40 and 90percent sulphur compounds, respectively.The presence of hydrogen sulphide in the HDN of isoquinoline resulted in an enhanced fraction of the neutral moiety.A reaction mechanism is suggested for the HDN of 2-methylquinoline and 2-methylpiperidine in the presence of hydrogen sulphide, in which the latter contributes to the higher degree of conversion due to the formation of corresponding sulphur compounds.
FORMATION OF SOME BICYCLIC SYSTEMS BY RADICAL RING-CLOSURE
Beckwith, Athelstan L. J.,Phillipou, George,Serelis, Algirdas K.
, p. 2811 - 2814 (2007/10/02)
The rates and stereochemistry of ring closure of the radicals (2), (9), (10), and (16) have been determined and rationalised.
