The Dehydrocyclization of C10 and Higher Alkylbenzenes

Commercial reforming catalysts have both metal and acid sites. Both could contribute to cyclization. If there are four or more carbon atoms in the side chain of a mono-alkylaromatic or ortho-substituted dialkylaromatic hydrocarbon, cyclization can yield either five- or six-membered rings. This multiplicity of reaction pathways helps to clarify the roles of the metal and acid components in dehydrocyclization and other reactions. 

Catalyst Dehydrogenation Activity Acid Activity Platinum Surface Area, Micromole CO/g 

TABLE I Reactions of n-Butylbenzene over Different Catalystsf-, b  

Dehydrocyclization of n-butylbenzene produces 1-methylindan, methyl-indenes, and naphthalene  

The primary products of -pentylbenzene cyclization are 1-ethylindan, 1-ethylindenes, and 1-methylnaphthalene. Secondary (consecutive) isomerization may produce dimethylindans, 2-ethylindan, the corresponding in-denes, and 2-methylnaphthalene  

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