Hydrocarbon series

There are a total of eighteen different hydrocarbon series, of which the most common constituents of crude oil have been presented - the alkanes, cycloalkanes, and the arenes. The more recent classifications of hydrocarbons are based on a division of the hydrocarbons in three main groups alkanes, naphthanes and aromatics, along with the organic compounds containing the non-hydrocarbon atoms of sulphur, nitrogen and oxygen. 

Methane, ethane, and propane are the first three members of the alkane hydrocarbon series having the composition, Selected properties of these... 

The straight-chain hydrocarbons represent just one group of straight-chain hydrocarbons, the saturated hydrocarbons known as the alkanes. There are other series of hydrocarbons that are unsaturated one of those is important in the study of hazardous materials. Additionally, the first hydrocarbon in another series is the only hydrocarbon important in that series. Each of these hydrocarbon series are briefly described below. 

The alkane series is also called the saturated hydrocarbon series because the molecules of this class have carbon atoms connected by single bonds only, and therefore have the maximum number of hydrogen atoms possible for the number of carbon atoms. These substances may be represented by the general formula C H2,I + 2 and molecules of successive members of the series differ from each other by only a CH2 unit. The line formulas and names of the first 10 members of the series, given in Table 21-2, should be memorized because these names form the basis for naming many other organic compounds. It should be noted that the first parts of the names of the later members listed are the... 

Silicon forms numerous hydrides that have counterparts in the hydrocarbon series. However, the silanes are named with respect to the number of silicon atoms present. For example, Si2Hs is known as disilane, Si3H8 is trisilane, and so on. The situation is similar for the germanium hydrides. 

The chemical energy content of fossil fuels generally parallels the H/C ratio as shown in Table 1. Methane has the highest heating value of the hydrocarbon series, corresponding to its high H/C ratio while coal has the lowest heating value. The normal physical state of fossil fuels also parallels the H/C ratio. Methane is a gas at ambient temperature and pressure conditions. Petroleum fractions are mobile liquids except for the heaviest fraction which can be solid at ambient temperature. Coal is a solid material. 

Temperature and molecular weight have a significant effect on surface tension (Table 2.3). For example, in the normal hydrocarbon series, a rise in temperature leads to a decrease in the surface tension, but an increase in molecular weight increases the surface tension. A similar trend, that is, an increase in molecular weight causing an increase in surface tension, also occurs in the acrylic series and, to a lesser extent, in the alkylbenzene series. 

Honig, R.E. Ionization Potentials of Some Hydrocarbon Series. J. Chem. Phys. 1948, 16, 105-112. 

Figure 4.39 Phase transition temperatures of hydrocarbon series...

Figure 6.10 Liquid density and the number of carbon atoms (a) five hydrocarbon series (b) four polar compound series...

Suppose that such electronic structure results had not been available, and that we had used instead the simplest bond-dissociation-energy method of estimating A Hj. The B.D.E for C-H bonds in the hydrocarbon series is [32] as 415 kJ/mole. Using the known heats... 

Whereas the hexa-1,3,5-triene/cyclohexa-l,3-diene rearrangement serves as a model reaction in the hydrocarbon series, the perfluoro analog behaves differently, as presented in Section 5.3.2.1. Photolysis of perfluorohexa-l,3,5-triene (8) in the gas phase yields per-fluorobicyclo[2.2.0]hex-2-ene (10) as the major product, presumably via perfluorocyclohexa-1,3-diene (9).4 Perfluoro(3-vinylcyclobutene) is formed as the minor product. Thermolysis of hexa-tricnc 8 gives cyclohexadiene 9.4 Photolysis of 9 provides bicyclohexene 10, which reverts to 9 thermally.5... 

Fluoroolefins are key compounds playing a fundamental role in synthetic fluoroorganic chemistry. Modification of the properties of the double bond by the introduction of fluorine atoms permits the development of reaction routes that are missing in the hydrocarbon series. This creates excellent opportunities for the syntheses of definite structures,... 

Another example in the C-glycosylated, unsaturated hydrocarbon series is methyl 2-deoxy-3,4-0-isopropylidene-2-C-methylene-/3-D-erythro-pentopyranoside (213), obtained90 in 55% yield by the reaction of methyl 3,4-0-isopropylidene-/3-D-eryfhro-pentopyranosid-2-ulose (212) with methylenetriphenylphosphorane n-butyllithium was used as a proton acceptor. Subsequent reduction of 213 with 10% palladium-on-charcoal led to a 7 1 mixture of the 2-epimeric methyl 2-deoxy-2-C-methylpentopyranosides (214 and 215, respectively). In the n.m.r. spectrum of 214, the H-l resonance appeared as a doublet at r 5.62 p.p.m., exhibiting aJia coupling constant of 8 Hz, thus indicating H-2 to be axial and, therefore, the D con-... 

The trithione -methides (3-methylene-1,2-dithioles) are iso-77-electronic with the heptafulvenes,71 and possess a basicity comparable to that of the latter. Some true 3-alkylatSd 1,2-dithiolium salts can be obtained by protonation of compounds 52. This method of preparation is rather narrowly limited, however, by the fact that the simple derivatives of 52 (as in the hydrocarbon series) are evidently very unstable and have not as yet been described. These dithiafulvenes become stable, easily handled compounds only when they contain aryl or typical acceptor residues (R and/or R = CN, C02R) in the 6-position.53, 72 This substitution, however, again as in the hydrocarbon series,73 lowers the basicity to such an extent that the dinitrile (52) (Rj = R2 = H, R = R = CN), for example, is not appreciably protonated even in pure trifluoroacetic acid.52... 

Silylated ketene acetals are more reactive than silyl enol ethers (Scheme 46), and the higher reactivity of cyclopentenes compared to cyclohexenes, which has already been reported for the hydrocarbon series (Scheme 41), is also observed for this class of compounds. The negative inductive effect of oxygen, which operates at the position of electrophilic attack, makes the bisenol ether (Scheme 46, right column, bottom) 20 times less reactive than the structurally analogous monoenol ether. 

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