Alkyl cyclohexanes

The reaction of the O-alkylated cyclohexan-l,3-diones 73 with p-substituted anilines in the presence of acetic acid is influenced by the nature of R in 73, yielding 4-anilinoxanthones 74 when R = H, but the condensed y-lactams 75 when R = Me (Scheme 51) <00T5947>. 

The Si excited-state lifetimes of cyclohexane and alkyl cyclohexanes are relatively short, all around 1-2 nsec however, their radiative rate coefficient —8 x 10 sec h R is the largest for the di- and trimethylcyclohexane group, —1.2 x 10 sec . 

Of the alkyl cyclohexanes, cyclohexane, methylcyclohexane, and all but one of the eight Cg isomers are included. 

Among the isomeric Cs alkyl cyclohexanes, the approximate relative amounts of the mono and dialkyl isomers are ethyl isomer, 1 sum of the seven dimethyl isomers, 7. 

The gasoline fraction of different crudes may be characterized by specifying the relative amounts of the following five main classes of hydrocarbons n-paraffins, branched paraffins, alkyl cyclopentanes, alkyl cyclohexanes, and alkyl benzenes. 

A series of amino-alkyl-cyclohexanes (e.g. MRZ-2/579) under recent development by Merz have been shown to attenuate the development of tolerance towards antinociception by morphine in rats (Parsons et al., 1999b Houghton et al., 2001). 

Parsons, C. G., Danysz, W, Bartmann, A., Spielmanns, P., Frankiewicz, T., Hesselink, M., Eilbacher, B., Quack, G. Amino-alkyl-cyclohexanes are novel uncompetitive NMDA receptor antagonists with strong voltage-dependency and fast blocking kinetics in vitro and in vivo characterization, Neuropharmacol. 1999b, 38, 85-108. 

Figs. 59 and 6o. Diagrams representing specific refraction vs. and specific parachor vs., based on A.P.I. data of n-alkanes, n-alkyl-cyclopentanes and n-alkyl-cyclohexanes at 20°C. ... 

Rammes G., Rupprecht R., Ferrari U., Zieglgansberger W., and Parsons C. G. (2001). The A-methyl-D-aspartate receptor channel blockers memantine, MRZ 2/579 and other amino-alkyl-cyclohexanes antagonise 5-HT3 receptor currents in cultured HEK-293 and N1E-115 cell systems in a non-competitive manner. Neurosci. Lett. 306 81-84. 

The need for benzene reduction is one of the determining factors in the way refiners will have to modify their process portfolio to meet future specifications. Apart from lowering the reformer severity, pre-fractionation and post-fractionation provide viable tools to reduce benzene in the gasoline pool. Pre-fractionation and subsequent hydrogenation of benzene is a typical solution. However, the products (cyclohexane and alkyl-cyclohexanes) are low in octane. Therefore, this option is only feasible if the refinery is not short in octane. The octane loss can be compensated for by the addition of oxygenates or preferably by the addition of alkylates. If more octane is needed, post-fractionation is one of the solutions. 

The EACN was found to depend on the oil molecular structure. Branching was not found to alter it significantly unless it is extensive, but cyclisation tends to cut it down definitely. EACN was found to be 3.5 for cyclohexane and (3.5 + n) for alkyl cyclohexanes with n carbon atoms in their alkyl chain benzene EACN was initially found to be close to 0 alkylbenzenes were found to have an EACN equal to the number of carbon atoms of their alkyl chain [4]. Recent findings with extremely pure surfactants tend to indicate that these results for aromatic oils might be erroneous, or at least misleading, because these solvents... 

Isomerization Products of Alkyl Cyclohexanes. Extensive isomerization of the reactant precedes the cracking of cycloparaffins. Table IV presents the analyses of the Ci0 cycloparaffin isomers formed... 

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