Decalin as solvent

In alicyclic hydrocarbon solvents with aromatic solutes, energy transfer (vide infra) is unimportant and probably all excited solute states are formed on neutralization of solute cations with solute anions, which are formed in the first place by charge migration and scavenging in competition with electron solvent-cation recombination. The yields of naphthalene singlet and triplet excited states at 10 mM concentration solution are comparable and increase in the order cyclopentane, cyclohexane, cyclooctane, and decalin as solvents. Further, the yields of these... 

The direct synthesis of anthraquinone from phthalic anhydride and benzene has been reported to proceed over zeolite Beta [50] in a shape selective manner. In a conventional anthraquinone synthesis, anthracene is used as a feedstock for oxidation. Once there is a shortage of it in the market, additional anthracene could be produced by isomerization of its isomer, viz. phenanthrene. This, however, is not possible by direct isomerization of the trinuclear aromatic system but involves the partially (symmetrically) hydrogenated species. Consequently, isomerization of symmetrical octahydrophenanthrene to symmetrical octahydro-anthracene was studied by Song and Moffatt [51]. As sketched in Figure 3, a high yield of symmetrical octahydroanthracene can be obtained over zeolite H-mordenite (ngj/nyy = 8) at 250 °C (liquid phase, decalin as solvent). These examples show that (shape selective) catalysis on zeolites is more and more expanding into the conversion of polycyclic aromatics, and we foresee continued interest and success in this field of zeolite catalysis. 

Ring-shift isomerization of 1,2,3,4,5,6,7,8-octahydro-phenantrene (syn-OHP) to 1,2,3, 4,5,6,7,8-octahydro-anthracene (syn-OHAn) was studied on several hydrogen- and Me-exchanged Y zeolites (Song and Moffatt 1993). La,H-Y zeolite (8.4 wt% La203) appears to be an active and selective catalysts. Thus, a selectivity to syn-OHAn of 44.9% at a conversion of 74.93% at 250°C (yield of 30.43) have been reported. However, the catalytic behaviour was strongly influenced by the solvent, and the best catalytic behaviour was obtained using decaline as solvent. 

It is a typically aromatic compound and gives addition and substitution reactions more readily than benzene. Can be reduced to a series of compounds containing 2-10 additional hydrogen atoms (e.g. tetralin, decalin), which are liquids of value as solvents. Exhaustive chlorination gives rise to wax-like compounds. It gives rise to two series of monosubstitution products depending upon... 

Mixtures of trioctylamine and 2-ethylhexanol have been employed to extract 1—9% by volume acetic acid from its aqueous solutions. Reverse osmosis for acid separation has been patented and solvent membranes for concentrating acetic acid have been described (58,59). Decalin and trioctylphosphine were selected as solvents (60). Liquid—Uquid interfacial kinetics is an especially significant factor in such extractions (61). 

Treatment of Decalin with acetyl chloride and aluminum chloride in ethylene chloride as solvent gives a complex mixture of products as shown (15). By variation of the reaction parameters, however, it is possible to maximize the yield of the remarkable reaction product, 10 j3-vinyl-/m j-Decalin l/8,r oxide (5). This vinyl ether undoubtedly... 

Fig. 6. Specific viscosity, r sp, as a function of the product c- [q] for narrowly distributed polystyrene in toluene (good solvent) (A) and frans-decalin (poor solvent) ( ) at 25 °C. Experimental data for the polystyrene/toluene system at 30 °C (taken from [65]) are represented by (O). 

BEP819195 75GEP2343462), and decaline (69T4649) have been used. Dowtherm A (b.p. 260°C) is used most widely this is a eutectic mixture of diphenyl ether (73.5%) and biphenyl (26.5%). It is superior to pure diphenyl ether (m.p. 26-27°C) because of its lower freezing point (12°C) (e.g., 46JA1204, 46JA1264). The cyclization can be carried out above 300°C when dibenzylbenzene is used as solvent. 

Though safer than the decomposition of pure, solid diazonium tetrafluoroborates, dediazoni-ation of these compounds mixed with inert solid salts cannot be scaled up to a large extent since heat exchange through large quantities of powdered solids rapidly becomes difficult. Thus, dediazoniation of arenediazonium tetrafluoroborates suspended in inert fluids is an alternative proposition.13105 141 175-219 220 In addition to the safety improvement, lower quantities of tar are formed using this technique. The inert fluid can be ligroin,143 petroleum ether,147 Decalin,3 or simple aromatic compounds,1-3,5,131-221 such as toluene, xylene, biphenyl, nitrobenzene,177 or quinoline. Simple esters have also been used as solvents in the dediazoniation... 

Optically active cis-decalins can be obtained from substrates such as 4 by a Heck-type reaction with PdCl2/(R)-l (1 1) as the catalyst.8 Addition of various silver salts improves the yield and enantioselectivity. For cyclization of 4 to 5, the highest enantioselectivity was observed by use of Ag3P04 and CaC03 (2 equiv. of each) with 1 -methyl-2-pyrrolidinone (NMP) as solvent (60°). 

The direct synthesis of (arene)Mo(CO)3 complexes from arene and Mo(CO)g is much more limited than for chromium (Scheme 4) [11,51]. The long reaction times at elevated temperature (e.g., ten days for (benzene)Mo(CO)3) and the high sensitivity to oxygen often results in low yields for substituted arenes. While (benzene)Mo(CO)3 (40) has been reportedly obtained in near quantitative yield, the yield was based on liberated CO rather than isolated complex [11]. In the author s laboratory, an isolated yield of 50% is more realistic for this procedure. The reaction time can be shortened by reacting Mo(CO)g in benzene in the presence of pyridine in an autoclave [52]. Toma and coworkers have described a different procedure that uses a double condenser system, and decalin plus ethylformate as solvent [53]. With a bath temperature of 240 °C this cuts the preparation time of the aniline complex 42 to 1 h (55% yield) (Scheme 4). In the authors laboratory the method is used routinely for the synthesis of complex 40 (18 h, 60% yield). 

Decalin (decahydronaphthalene), benzene, 1,4-dioxane, and ethanol may be used as solvents for the photolysis. In an alternative procedure, volatile materials swept from the photolysis vessel are condensed in a dry ice trap. This cold mixture is added to a flask containing a magnetically stirred solution of dimsyl anion in dimethyl sulfoxide, and fractionation at reduced pressure provides a solution of bicyclopentene in tetrahydrofuran. 

Ogawa et al. (23) used a HFIP/toluene (20 80) mixture as the eluant for nylon 12. Column fractionation of the same polymer was also performed using benzyl alcohol/decalin as the solvent/nonsolvent pair. They were able to demonstrate that in the HFIP/toluene mixture, polystyrene narrow standards and nylon 12 narrow fractions were in compliance with the universal calibration... 

Fractionations of nylon 12 by column fractionation and by preparative-scale SEC in HFIP/CFjCOONa and in HFIP/toluene (20 80) mixtures were carried out by Ogawa and Sakai (24). They found that SEC fractionation in HFIP/toluene (20 80) is more effective than in HFIP/CFjCOONa. Column fractionation using benzyl alcohol and decalin as the solvent/nonsolvent pair is more practical in producing large quantities of narrow fractions, however. Molecular weight characterization of the fractions was accomplished by analytical SEC in HFIP/toluene (20 80) and by static LALLS work in straight HFIP. 

Polystyrene was employed in GLC as solvent for the following solutes benzene, cyclohexane and n-pentane [3], n-hexadecane [88], normal, branched and cyclic alkanes, single and dinuelear aromatic hydrocarbons, ds- and ira -decaline [60], n-octane, n-decane, chloroform, carbon tetrachloride, benzene, nitromethane and ethanol [89], methanol, carbon sulphide, 1,2,4-trimethylbenzene, pentane and tri-isopropylbenzene [90]. Some of the polymers-solute systems mentioned are encountered in other contributions [31, 43, 91 — 93]. The results differ in respect of y" and Xj2 values and their temperature variation. The possible somces... 

Significant differences in the acetylation of naphthalene with acetic anhydride (2 1 molar ratio) over HBEA are observed with decalin or sulfolane as solvents the diffoent hydrophilicities of these solvents dramatically inflnence the resulting naphthalene conversion. The hydrophilic sulfolane into-acts more strongly with the zeolite surface, thus blocking the acid sites that are less available for the acylation reaction (naphthalene conversion = 14%) on the contrary, the hydrophobic decalin enables the adsorption of acetic anhydride and increases the rate of acylation reaction (naphthalene conversion=25%). Due to the defined structure of the HBEA, the selective formation of isoma-15 is probably achieved via a restricted transition state selectivity (15 13=81 19 at 35% naphthalene conversion). It must be underlined that different secondary products are, in general, produced on the catalyst surface due to consecutive reaction of the products. 

Chiarizia and Danesi (8) have demonstrated the feasibility of using two SLM systems in series for the removal of lanthanides and actinides containing Pu, Pu, Np (10 M) and c. The first SLM (SLM-1) used the TRUEX process solvent (0.25 M CMPO + 0.75 TBP in decalin) as the supported liquid membrane and 1 M formic acid and 0.005 M hydroxylammonium formate as the strippant. For the... 

The rubber particle size of heterophasic polypropylene can be described by molecular weight. The molecular weight of an ethylene propylene copolymer can be described by its intrinsic viscosity, as measured by the XS fraction. The p of an ethylene propylene copolymer is generally determined at 135°C using decaline as a solvent, see Fig. 2.21. 

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