Dehydrogenation of tetralin

Catalytic Dehydrogenation of Tetralin over Carbon-Supported Platinum Nanoparticles under Superheated Liquid-Film... 

This high-potential quinone is second in effectiveness to 2,3-dichloro-5,6-dicyano-1,4-benzoquinone in the dehydrogenation of tetralin, acenaphthene, and dibenzyl in benzene at SO"." Kinetic studies are reported. The dehydrogenation of the 1,1-dimethyltetralin is attended with Wagner-Meerwein rearrangement ... 

For olefins to be intermediates in the hydrogenation mechanism, the process must necessarily be reversible. Dihydronaphthalene was indeed found in the products of the dehydrogenation of tetralin over activated carbon by Shuikin et al. (6S). 

Fig. 54. The dependence of the activation energy of dehydrogenation of tetralin in kcal/mole, and atomic radius of metals, r, in A, on the atomic number, n 435).

Fig. 55. The linear relationship between the activation energy of the dehydrogenation of tetralin e, in kcal/mole, and the parameter of the lattice of rare earth elements in...

The most important process to produce 1-naphthalenol was developed by Union Carbide and subsequently sold to Rhc ne-Poulenc. It is the oxidation of tetralin, l,2,3,4-tetrahydronaphthalene/719-64-2] in the presence of a transition-metal catalyst, presumably to l-tetralol—1-tetralone by way of the 1-hydroperoxide, and dehydrogenation of the intermediate ie, l-tetralol to 1-tetralone and aromatization of 1-tetralone to 1-naphthalenol, using a noble-metal catalyst (58). 1-Naphthol production in the Western world is around 15 x 10 t/yr, with the United States as the largest producer (52). 

In contrast, a catalytic reaction pair of tetralin dehydrogenation/naphthalene hydrogenation (Equation 13.3) is another choice for stationary applications. Although the storage densities of tetralin are relatively low (3.0 wt%, 28.2 kg-H2/m3), rates of absorbing and desorbing hydrogen... 

Dehydrogenation activities, compared for tetralin and decalin [5,12] under the same superheated liquid-film conditions over the same Pt/C catalyst, exhibited around 3.9-63 times preference of tetralin (Table 13.3), which can certainly be ascribed to advantageous adsorption due to the a-bonding capability of its aromatic part [17-19]. It was, thus, confirmed experimentally that tetralin is superior to decalin as the organic hydrogen carrier for stationary applications in terms of rapid hydrogen supply or power density, provided that the density of fuel storage is unimportant. 

Time courses of dehydrogenation activities with carbon-supported platinum catalyst under superheated liquid-film conditions in laboratory-scale continuous operation. Catalyst platinum nanoparticles supported on granular activated carbon (Pt/C, 5 wt-metal%), 1.1 g. Feed rate of tetralin 0.5 mL/min (superheated liquid-film conditions). Reaction conditions boiling and refluxing by heating at 240°C and cooling at 25°C. (Reproduced from Hodoshima, Sv Shono, A., Satoh, Kv and Saito, Yv Chem. Eng. Trans8,183-188, 2005. With permission.)... 

Labelling experiments provided the evidence that the Fe1- and Co1-mediated losses of H2 and 2H2 from tetralin are extremely specific. Both reactions follow a clear syn- 1,2-elimination involving C(i)/C(2) and C(3)/C(4), respectively. In the course of the multistep reaction the metal ions do not move from one side of the rr-surface to the other. The kinetic isotope effect associated with the loss of the first H2 molecule, k( 2)/k(Y)2) = 3.4 0.2, is larger than the KIE, WFLj/ATHD) = 1.5 0.2, for the elimination of the second H2 molecule. A mechanism of interaction of the metal ion with the hydrocarbon n-surface, ending with arene-M+ complex 246 formation in the final step of the reaction, outlined in equation 100, has been proposed241 to rationalize the tandem MS studies of the unimolecular single and double dehydrogenation by Fe+ and Co+ complexes of tetraline and its isotopomers 247-251. 

DDQ was first introduced for the dehydrogenation of hydroaromatic compounds, such as tetralin and bibenzyl, which yield naphthalene and stilbene, respectively. A benzene ring or an olefinic bond provides sufficient activation, although it is sometimes difficult to force the reaction to completion. Phis high-potential quinone has since found wide a )plication, jiarticularly... 

Tetrachloroethane, purification of, 176 Tetradecanoic acid, 938, 940, 941 n-Tetradecyl bromide, 283 1 2 3 4-Tetrahydrocarbazole, 852 Tetrahydrofuran, 271 Tetrahydrofurfuryl chloride, 896, 901 Tetrahydropyran, 271 Tetralin, dehydrogenation of, 948, 949 purification of, 949 a-Tetralone, 728, 737 Tetramethyl base, 987 pp -Tetramethyldiaminodiphenyl-methane, 987... 

Dehydrogenation (the conversion of alicyclic or hydroaromatic compounds into their aromatic counterparts by removal of hydrogen - and also, in some cases, of other atoms or groups) has found wide application in the determination of structure of natural products containing complex hydroaromatic systems. Dehydrogenation is employed also for the synthesis of polycyclic hydrocarbons and their derivatives from readily accessible synthetic hydroaromatic compounds. The general process is illustrated by the conversion of tetralin into naphthalene. 

The elimination of hydrogen is very common in plasmas. Dehydrogenation of compounds like tetraline, acenaphthene, tetrahydroquinoline or in-dane has been carried out with excellent results. Elimination of hydrogen... 

Dehydrogenation. Andersen et alreport that treatment of sesquiterpenes with trifluoroacetic acid leads to dehydrogenation with partial aromatization. The reaction is particularly suitable for production of tetralins. Thus treatment of the cadinene hydrocarbons (1)—44) in n-decane solution for a few minutes with excess TFA at room... 

Aromatization. The high-potential quinone was introduced for use in the dehydrogenation of hydroaromatic compounds for example, in boiling benzene it converts tetralin into naphthalene and acenaphthene into acenaphthylene. The hydroaromatic compound with a blocking group (I) undergoes aromatization with a 1 2-shift of a methyl group. 

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