Propanation, cyclopropanation

To name an alkane in which the carbon atoms form a single chain, we combine a prefix denoting the number of carbon atoms with the suffix -ane (Table 18.1). For example, CH,—CH, (more simply, CH,CH,) is ethane and CH,—CH2—CH, (that is, CH,CH2CH,) is propane. Cyclopropane, C,H6 (15), and cyclohexane, C6H12 (16), are cycloalkanes, alkanes that contain rings of carbon atoms. 

TABLE 3. Overlap values calculated using non-ortliogonal hybrid orbitals within valence bond calculations of propane, cyclopropane and cyclobutane"... 

Kinetic acidities have been reported for methane, ethane, propane, cyclopropane, isobutane, neopentane, tetramethylbutane, norbornane, nortricyclene, and adamantane by tritiodeprotonation or deuteriodeprotonation in cyclohexylamine catalyzed by caesium cyclohexylamide.13... 

FIGURE 2. G-values of the various products in the radiolysis of (a) propane-cyclopropane mixtures, (b) propene-cyclopropane mixtures as a function of the concentration (e = mole fraction). (Taken from Foldiak and Horvath with the permission of the authors)... 

Also shown in Figure 1.11(c), for purposes of comparison, are three neutral classically bonded hydrocarbons, propane, cyclopropane, and cyclopropene. For these systems, and for electron-precise systems in general, the number of electrons available for bonding (n) is equal to the number of AOs available (and so precisely the right number to fill the nil bonding MOs). 

In this work, a gas chromatographic system has been used to obtain binary sorption equilibria for nitrogen-oxygen, methane-ethane and propane-cyclopropane mixtures on 5A molecular sieve. The experimental measurements have also been compared with the predictions from the statistical thermodynamic model of Ruthven (11). The model is capable of predicting binary sorption equilibria from the parameters derived from the pure-component isotherm measurements. 

For the system of propane-cyclopropane, the problem of baseline drift and noise was encountered because of the closeness... 

Table III. Comparison of experimental and predicted slopes for propane-cyclopropane mixture at 398K and different compositions...

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 overlap can be improved somewhat by adjustment of hybridization. Increased p character in the C-C bonds reduces the interorbital angle and improves overlap, which means that the C-H bonds must have increased s character. Compared to ethane or propane, cyclopropane has slightly shorter C-C and C-H distances and an open CH2 bond angle," which is consistent with rehybridization. The C-H bonds in cyclopropane are significantly stronger than those in unstrained hydrocarbons, owing... 

The SSTM also yields a direct extension to binary and multicomponent systems [24] allowing multicomponent equihbria to be predicted directly from the Henry constants and saturation capacities for the pure components. This approach has been shown to work well for some systems such as propane-cyclopropane in 5A zeolite. For CH4-CO2 in 5A and 13X zeolites it provides a good prediction of the binary isotherm at elevated pres-... 

FIGURE 4.16. Equilibrium diagram (a) and X-Y diagram (b) for sorption of propane-cyclopropane mixtures on 5A zeolite at E 8 torr, T = 273 K. Theoretical curves are calculated from Eq. (3.102) with the parameters derived from the single-component isotherms. (Reprinted with permission from ref. 42. Copyright 1977 American Chemical Society.)... 

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