Cyclohexane Hexahydrobenzene, Hexamethylene

Benzene can be quantitatively transformed into cyclohexane by hydrogenation over either a nickel or platinum catalyst. This reaction is carried out at 210°C and 350-500 psi, sometimes in several reactors placed in series. The yield is over 99%. 

Although many catalytic reactions are not well understood, a large amount of work has been done on hydrogenations of double bonds. The metal surface acts as a source of electrons. The tt bonds as well as hydrogen atoms are bound to this surface. Then the hydrogen atoms react with the complexed carbons one at a time to form new C—H bonds. No reaction occurs without the metal surface. The metal in effect avoids what would otherwise have to be a free radical mechanism that would require considerably more energy. The mechanism is outlined as follows. 

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CYCLOHEXANE AND DERIVATIVES Cyclohexane, Hexamethylene, Hexanaphthene or Hexahydrobenzene (called Cyclohexan or Hexa-hydrobenzol in Ger),... 

Hexamethylene, C6H12, cyclohexane, or hexahydrobenzene, is found in Caucasian petroleum, which consists essentially of this hydrocarbon and its homologues, which are called napthenes. Hexamethylene is prepared by the method of Seba-tier and Senderens, which consists in reducing a compound by passing a mixture of its vapor and hydrogen over finely divided nickel which is heated between 150° and 200° —... 

Cyclohexane Sl-klo- hek- San [ISV] (ca. 1909) (hexamethylene, hexahydrobenzene) n. C6Hi2. a saturated hydrocarbon with a six-membered ring, cyclohexane is derived from the catalytic hydrogenation of benzene, and is used as a solvent for cellulosics and as an intermediate in the production of nylon (See image). 

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