Endo-Tetrahydrodicyclopentadiene from

Preparation B. Ault and Kopet2 describe as an introductory organic experiment a procedure for the preparation of adamantane by isomerization of endo-tetrahydrodicyclopentadiene by the method of Schleyer but the product is isolated from a hexane extract of the reaction mixture as the beautifully crystalline inclusion complex with thiourea.3 As noted in 1, 1164, the ratio in this complex is 3.4 molecules of host per molecule of guest hydrocarbon. Although the reaction time is only 1 hour, the yield (15%) is about the same as that reported for a reaction time of 8-12 hours. 

As can be seen, the relative volatility of both propylbenzene and 4-methylethylbenzene were more than 1.500, and the relative volatility of endo-Tetrahydrodicyclopentadiene was less than 0.600. The further away from 1 the relative volatility of them is, the more easily they can be separated from indane. Thus, the separation of the remaining components become complicated. 

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