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INDEX cycloalkanes

Values for hydrocarbons other than alkynes and alkadienes can be predicted by the method of Suzuki et al. The best model includes the descriptors T, P, the parachor, the molecular surface area (which can be approximated by the van der Waals area), and the zero-order connectivity index. Excluding alkynes and alkadienes, a studv for 58 alkanes, aromatics, and cycloalkanes showed an average deviation from experimental values of about 30 K. [Pg.418]

Although Hantzsch-Widman system works satisfactorily (if you can remember the rules) for monocyclic compounds, it is cumbersome for polycyclic compounds. In the case of oxiranes it is simplest for conversational purposes to name them as oxides of the cycloalkenes or epoxy derivatives of the corresponding cycloalkanes. The oxabicycloalkane names seem preferable for indexing purposes, particularly because the word oxide is used in many other connections. [Pg.661]

Because of the chemical inertness of the saturated aliphatic hydrocarbons and of the closely related cycloalkanes, no satisfactory crystalline derivatives can be prepared. A pure sample may be characterised by consideration of such physical properties such as the boiling point, the refractive index (and/or the density), and these physical constants are listed in Table 10.1. If required, confirmation of structure should be sought from a more detailed study of appropriate spectra, particularly 13C-n.m.r., and mass spectra. [Pg.1235]

Figure 16-3. Viscosity index and structural types in lubricating oil. (a) Commercial solvent-extracted lubricating stocks. (b) Aromatic-free fractions. 1 Non-condensed cycloalkanes. 2 Condensed cycloalkanes. 3 Isoparaffins. 4 Aromatics. From data by Andre and O Neal [11]. Figure 16-3. Viscosity index and structural types in lubricating oil. (a) Commercial solvent-extracted lubricating stocks. (b) Aromatic-free fractions. 1 Non-condensed cycloalkanes. 2 Condensed cycloalkanes. 3 Isoparaffins. 4 Aromatics. From data by Andre and O Neal [11].
Viscosity index of fractions from thermally diffused ng oil. (a) Isoparaffins. (b) Condensed cycloalkanes. (c) nsed cycloakanes. (d) Aromatics. From data by Melpolder c ... [Pg.496]

As a result of their inertness no general suitable derivative exists for alkanes and cycloalkanes Characterization IS based only on the physical constants given in the Table melting and boiling points, index of refraction and density Any laboratory text-book will give adequate directions for the determination of these constants... [Pg.2]

In each homologous alkane or cycloalkane family, the physical constants such as boiling point and refractive index are very useful. Specific gravity measurements even in the capillary mode still need relatively large quantities of compound. The most employed method for tentative identification and relative quantification of hydrocarbons is gas chromatography (GC). This method will be discussed in detail for separation of mixtures. [Pg.301]

Among the multitude of organic compounds, there is a small number of objects with p 0 (all types of acyclic compounds most topologically relevant to n-alkanes). The increase in number of cycles in the molecules leads to the increase of p up to 0.3-0.5 (cycloalkanes, arenes, etc.), 0.5-0.8 (naphthalenes, biphenyl, etc.), and 1.0 and more retention index units per degree (i.u./deg) for tri- and polycyclic structures. Hence, it is not surprising that RI data for isoalkanes, ethers, esters, etc. being measured at different conditions, are in good accordance with each other (standard deviations of randomized interlaboratory values are not more than 1-3 i.u.). The same statistical characteristics for substituted benzenes is about 8 i.u., and for naphthalenes and other condensed arenes, it may exceed 10-15 i.u. [Pg.1308]

The Wiener index (W) was also used for calculating the HPLC retention time of PAHs, n-alkanes, and cycloalkanes. [Pg.2359]

We have already seen that J informs us of the overall atomic excitation within a cycloalkane and this is why it correlates with both strain and CH bond length (Table 2). However, there can be no correlation between J and CC bond lengths. The latter depend on the number of bonding electron pairs in S,Tg, not on T. Hence, it is the index V, not J, that informs us about the variation of CC bond lengths. Experimental results are in agreement with expectations (Table 2). However, while J often correlates with strain and carbon acidity in cycloalkanes, there is simply no reason to assume that this will always be true. An example will serve to illustrate this point. [Pg.93]


See other pages where INDEX cycloalkanes is mentioned: [Pg.327]    [Pg.211]    [Pg.886]    [Pg.301]    [Pg.29]    [Pg.496]    [Pg.497]    [Pg.1576]    [Pg.11]    [Pg.327]    [Pg.246]    [Pg.320]    [Pg.219]    [Pg.26]    [Pg.814]    [Pg.409]   
See also in sourсe #XX -- [ Pg.102 , Pg.103 , Pg.104 , Pg.105 , Pg.106 ]




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