Dehydrogeno-aromatization

Although the suspended catalysts under boiling and refluxing conditions were active for dehydrogeno-aromatization of alkyl-substituted cyclohexanes, the levels of reaction rates were unsatisfactorily low. A breakthrough toward low catalytic activities was accomplished by our introduction of "superheated liquid-film concept" (vide infra) [30]. 

Because the cis-decalin molecule extends its two methine carbon-hydrogen bonds on the same side in contrast to frans-decalin, the carbon-hydrogen bond dissociation of adsorbed decalin would be advantageous to the cis-isomer on the catalyst surface (Figure 13.17). A possible reaction path by octalin to naphthalene in dehydrogeno-aromatization of decalin will be favored to the cis-isomer, since its alkyl intermediate provides the second hydrogen atom from the methine group to the surface active site easily. 

Takaiwa, S., S. Hodoshima, H. Arai, and Y. Saito, Liquid-phase dehydrogeno-aromatization catalysis of decalin for pure hydrogen/air fuel cell. /. Hydrogen Energy Syst. Soc. Jpn., 26(2), 44-49 (2001). 

Yukawa, K., X. Li, T. Fujii, T. Kawamura, and Y. Saito, Dehydrogeno-aromatization of cyclohexanes with suspended noble-metal catalysts. /. Chem. Soc. Faraday Trans., 89, 3641-3644 (1993). 

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