Olefin hydrocarbons behavior

On the other hand, it is interesting to use the supercritical C02 as an alternative solvent for various photochemical reactions, particularly for photo-initiated oxidation reactions, due to the non-ignitability of C02. Thus we are studying photo-induced oxidation reactions of ternary mixtures of hydrocarbon/02/C02. Partially oxidized products have been found to be produced in the case of C Hg, ethylene (C2H4) and cyclohexane (C6H,2) which have been studied so far. The present paper mainly reports the case of C Ii, in order to understand the behavior of typical olefinic hydrocarbons which are expected to trap some active species during the reaction. 

Every teacher of the first course of organic chemistry, towards its beginning, emphasizes the different behavior of saturated and olefinic hydrocarbons towards halogens. The influence of ring strain is discussed rather later in the course. And a good thing too, for... 

Steady-state operation was quickly achieved under SCF conditions and the SCF-FT process has a marked effect on the hydrocarbon product distribution with a shift to higher carbon number products owing to enhanced heat and mass transfer from the catalyst surface. In addition, an obvious difference in the olefin content was observed where the 1-olefin content in the SCF phase was always higher than in the gas phase. Based on the experimental observations, a mechanistic explanation is provided for the difference of the reaction behavior under supercritical and gas-phase environments. 

Several programs have been devoted principally to studies of hydrocarbons of a given type. Generalizations within the group were developed. Thus paraffins (26, 50, 120, 176), olefins (11, 15, 16, 68, 79, 81, 121, 146, 147), aromatics (7, 29, 47, 66, 83, 124, 140), naphthenes (66, 122), and diolefins and acetylenes (97, 121, 163, 164) have been centers of attention. Several papers describe the antiknock behavior of gaseous hydrocarbons (1, 65, 149, 172, 184) ... 

C5- and C6- cyclizations are parallel reactions. Csicsery has shown that isomerization of tetralin to methylindan over platinum-alumina at 371°C is extremely slow (22). Davis and Venuto provided further evidence by showing that methylindan is also not converted to tetralin or naphthalene over platinum on silica-alumina (23). This behavior is similar to that observed in the cyclization of aliphatic hydrocarbons. Davis and Venuto also reported that the major aromatic products obtained from ten C8-C9 paraffins and olefins at 482°C are only formed by direct six-membered ring... 

The transformation was called an homologation reaction because essentially it consisted in going from one alcohol to an alcohol containing one carbon atom more than the starting material (Wender, Levine, and Orchin, 14). Tertiary alcohols reacted most rapidly, secondary alcohols less rapidly and primary alcohols only very slowly. It was of considerable importance to ascertain whether the olefin intermediate was essential and for this purpose, methanol and benzyl alcohol, neither of which can dehydrate to an olefin, were used in the reaction. Both compounds, contrary to other primary alcohols, reacted quite rapidly and gave the homologous alcohol of the methanol converted, about 40 mole per cent went to ethanol and with benzyl alcohol, a 30% yield of 2-phenylethanol was secured. In both examples, however, reduction products were also present of the methanol converted, 8 mole per cent went to methane and from benzyl alcohol, a 50 to 60% yield of toluene was secured. The conversion of methanol to methane appears to be the only case in which an appreciable quantity of hydrocarbon is secured from a purely aliphatic alcohol. The behavior of benzyl alcohol and its derivatives will be discussed later. 

I -CycloatUition, 22 222 2, 118 3, 87-88). Two reviews have been published recently on the 1,2-cycloaddition of dichloroketene to olefins and dienes. In general, the best yields of cyclobutanones are obtained when the dchydrochlorination of dichloroacetyl chloride with triethylamine is conducted between 30 and 50° in a hydrocarbon solvent containing an excess of the ketenophile. The following reactivity sequence has been observed in the behavior of various keienes with cyclopentene ... 

Diffusive and convective transport processes introduce flexibility in the design of catalyst pellets and in the control of FT synthesis selectivity. Transport restrictions lead to the observed effects of pellet size, site density, bed residence time, and hydrocarbon chain size on chain growth probability and olefin content. The restricted removal of reactive olefins also allows the introduction of other intrapellet catalytic functions that convert olefins to other valuable products by exploiting high intrapellet olefin fugacities. Our proposed model also describes the catalytic behavior of more complex Fe-... 

When olefins chemisorb on metal surfaces (in the absence of hydrogen), substantial disruption of the molecules usually occurs measurements of heats of adsorption or of infrared spectra of adsorbed species are therefore of limited utility in establishing behavioral patterns, and more reliance should perhaps be placed on indirect assessments of chemisorption strengths arising from kinetic analysis of reacting systems. This information is of two kinds (a) the sequence of chemisorption strengths of an olefin on a series of metals, and (b) the sequence of chemisorption strengths of different unsaturated hydrocarbons on one metal. 

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