Cyclopropanes Ethylene

As noted above, it is long-established that cyclopropane has olefinic character. If this cyclopropane-ethylene analogy were strictly thermochemically correct, then the difference of the enthalpies of formation of vinyl-X and cyclopropyl-X would not depend on the affixed group X. Equivalently, the enthalpy of formation difference quantity <517 (Vi, Cypr, X) would be independent of X (equation 17). 

Very recently, Namta and co-workers (45) demonstrated reversible encapsulation of hydrocarbons into the hemicarcerand container 22 (Fig. 10). Methane, ethane, propane, cyclopropane, ethylene, and acetylene were trapped in CDCI3, showing the K ssoc values between 10 (ethane, cyclopropane) and 130... 

The hydrocarbons acetone, benzene, butene, cw-butene, cyclohexane, cyclopentane, cyclopropane, ethylene, isobutene, isooctane, methylcyclohexane, propylcyclohexane, neopentane, propyne, franj-hutene, and toluene. 

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