- Silylium ion/phosphane lewis pairs
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The reactivity of a series of silylium ion/phosphane Lewis pairs was studied. Triarylsilylium borates 4[B(C6F5)4] form frustrated Lewis pairs (FLPs) of moderate stability with sterically hindered phosphanes 2. Some of these FLPs are able to cleave dihydrogen under ambient conditions. The combination of bulky trialkylphosphanes with triarylsilylium ions can be used to sequester CO2 in the form of silylacylphosphonium ions 12. The ability to activate molecular hydrogen by reaction of silylium ion/phosphane Lewis pairs is dominated by thermodynamic and steric factors. For a given silylium ion increasing proton affinity and increasing steric hindrance of the phosphane proved to be beneficial. Nevertheless, excessive steric hindrance leads to a breakdown of the dihydrogen-splitting activity of a silylium/phosphane Lewis pair.
- Reissmann, Matti,Schaefer, Andre,Jung, Sebastian,Mueller, Thomas
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p. 6736 - 6744
(2014/01/06)
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- A novel catalyst for alkylation of benzene
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In this research, acid-activated and pillared montmorillonite were prepared as catalysts for alkylation of benzene with 1-decene for production of linear alkyl bebzene (LAB). The catalysts were characterized by X-ray diffraction (XRD), FT-IR spectroscopy,
- Faghihian, Hossein,Mohammadi, Mohammad Hadi
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p. 962 - 968
(2013/02/22)
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- Liquid phase alkylation of benzene with dec-1-ene catalyzed on supported 12-tungstophosphoric acid
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The liquid phase alkylation of benzene with dec-1-ene was catalyzed by 12-tungstophosphoric acid (WP) supported on different solids (ZrO2, SiO2, activated carbon and boehmite-Al2O3). Catalysts prepared with 20 w
- Hernández-Cortez,Martinez,Soto,López,Navarrete,Manríquez,Lara,López-Salinas
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scheme or table
p. 346 - 352
(2010/08/06)
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- Process for the production of phenylalkanes using a hydrocarbon fraction that is obtained from the Fischer-Tropsch process
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A process for the production of phenylalkanes comprising a reaction for alkylation of at least one aromatic compound by at least one hydrocarbon fraction that is directly obtained from the Fischer-Tropsch process comprising linear olefins that have 9 to 16 carbon atoms per molecule and oxygenated compounds is described. Said alkylation reaction is carried out in a catalytic reactor that contains at least one reaction zone that comprises at least one acidic solid catalyst, and said hydrocarbon fraction does not undergo any purification treatment prior to its introduction into said reaction zone.
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Page/Page column 4
(2008/06/13)
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- Catalytic Systems Based on Aluminum Chloride in Alkylation of Benzene with Olefins
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Two types of catalytic systems based on aluminum chloride and transition metal halides are prepared: mixed systems AlCl3-MeX (MeX is nickel, cobalt, copper, iron, tin, zinc, manganese, magnesium, potassium, or sodium chloride) and supported systems AlCl3/SiO2 and AlCl2·MeX/SiO2 (MeX is cobalt, nickel, or manganese chloride). Optimal conditions are found for preparation of catalytic systems based on aluminum chloride. These systems are studied in alkylation of benzene with olefins: ethene, propene, α-decene, and commercial C10-C14 fraction. Additives of nickel and cobalt chlorides increase the yield of ethyl- and propylbenzenes, simultaneously decreasing the yield of polyalkylbenzenes. Supported catalysts containing CoCl2, NiCl2, and FeCl3 additives increase the yield of monoalkylbenzenes in alkylation of benzene with higher olefins; additives of tin, zinc, and magnesium chlorides decrease the yield of monoalkylbenzenes; copper chloride is an inert additive. The yield of monoalkylbenzenes in alkylation of benzene with higher α-olefins in the presence of supported catalysts is 8-10% higher than in the presence of straight AlCl3. Preparation of supported catalytic systems requires 4-5 times smaller amount of aluminum chloride than preparation of binary systems.
- Polubentseva,Duganova,Mikhailenko
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p. 614 - 618
(2007/10/03)
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- Equilibria of isomeric transformations and relations between thermodynamic properties of secondary alkylbenzenes
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Equilibria of mutual transformations of monoamylbenzenes and diamylbenzenes (AmB), monohexylbenzenes (HxB), monoheptylbenzenes (HpB), and monodecylbenzenes (DB) have been studied in the liquid state over the range 273 to 423 K in the presence of 3 to 9 mass per cent of AlCl3.Values of ΔfH0m and ΔfS0m for the reactions studied have been calculated from the temperature dependences of the equilibrium constants.Below are given the reactions and the corresponding values for ΔfH0m/(kJ.mol-1) and ΔfS0m/(J.K-1.mol-1): 3-AmB=2-AmB, -(0.16 +/- 0.08), (8.45 +/- 0.23); 3-HxB=2-HxB, -(0.30 +/- 0.07), (3.85 +/- 0.21); 3-HpB=2-HpB, -(0.21 +/- 0.07), (3.52 +/- 0.22); 3-DB=2-DB, -(0.23 +/- 0.14), (3.51 +/- 0.43); 4-HpB=3-HpB, (0.02 +/- 0.41), (7.57 +/- 1.29); 4-DB=3-DB, (0.09 +/- 0.41), (1.69 +/- 1.28); 5-DB=4-DB, -(0.01 +/- 0.09), (0.18 +/- 0.25).For para-to-meta transformations of diamylbenzenes the average molar reaction enthalpy is -(0.26 +/- 0.46)kJ.mol-1 and the intrinsic change of molar entropy is -(0.99 +/- 1.2)J.K-1.mol-1.It is shown that for the calculation of enthalpies of formation of secondary alkylbenzenes correlations can be used which do not take into account the position of the phenyl substituent on the aliphatic hydrocarbon chain.The calculation of enthalpies of formation of normal and secondary alkylbenzenes in the liquid state at 298.15 K is made on the basis of experimental and literature values.
- Pimerzin, A. A.,Nesterova, T. N.,Rozhnov, A. M.
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p. 641 - 648
(2007/10/02)
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