Water in toluene

X 10 cm by measuring molecularly dispersed water in toluene and by correcting for local viscosity differences between toluene and these microemulsions [36]. Values for Dfnic were taken as the observed self-diffusion coefficient for AOT. The apparent mole fraction of water in the continuous toluene pseudophases was then calculated from Eq. (1) and the observed water proton self-diffusion data of Fig. 9. These apparent mole fractions are illustrated in Fig. 10 (top) as a function of... 

Co2(CO)8 with HC1 gas in the presence of 15-crown-5 and water in toluene. This led to a complex species which included seven-coordinate pentagonal bipyramidal Co11 centers (98) which included the metal ion in the macrocyclic polyether.422... 

B = ml of water in toluene C = Density of water at temp of the water bath... 

Pyrolysis of the quaternary ammonium hydroxide (330) by azeotropic removal of water in toluene in the presence of phenothiazine gave a 19% yield of the dimer (331), probably via 2,5-dimethylene-2,5-dihydrothiophene (60JA1428). Extension of this process to a mixture... 

We have examined the photosensitized reduction of a series of + 4,4 -bipyridinium salts, CnV2+, (2), (where n=l-16) with Ru(bpy)l as sensitizer and (NHi jEDTA as electron donor in a water-in-toluene microemulsion media. Under steady state illumination the quantum yield of CjjVt" formation strongly depends on the alkyl chain length of the electron acceptor (Figure 4). It improves as the hydro-... 

Table II. Charge separation yields and recombination rates in the photosensitized reduction of CnV2 in water-in-toluene microemulsions (6)...

A slightly modified synthesis of dihydrobenzo[c]furan was achieved, in which the key reaction involved the exposure of a dibromide to dry alumina and one equivalent of water in toluene instead of in hexanes <07TL3039>. Another synthesis of dihydrobenzo[c]furans was reported by Hashmi and Teles <07SL1747> and an example is depicted below. Base-promoted cycloaddition of 1-aryl- or l-aryl-7-substituted-4-oxahepta-1,6-diynes in DMSO were found to involve an anionic intramolecular Diels-Alder reaction, and also resulted in the formation of dihydrobenzo[c]furans <07JA4939>. 

Figure 6. Cyclic mechanism for photoinduced electron transfer across the interface of a water-in-toluene microemulsion. Key A, oxidative half-cell and B, reductive...

This led to the inclusion of two types of particles into the emulsions and the formation of multiple emulsions. For example, hydrophobically modified particles were dispersed in toluene, while hydrophilically modified particles were dispersed in water. Emulsification of this system produced water-in-toluene-in-water or toluene-in-water-in-toluene multiple emulsions. Formulations of one type over the other were achieved... 

For the more sandy soils with low water content, toluene may be used successfully due to the solubility of toluene in water and the azeotropic mixture of water in toluene. An example of this is the determination of PAH (see ISO 13877). Soxhlet extraction with azeotropic mixtures e.g. acetone n-hexane (60-40% m/m, bp 50°C) may be very useful if a more polar extraction solvent is required. 

Two more titanium compounds are known which contain a chelating O-functionalized cyclopentadienyl ligand. One of them is the siloxo complex 16TiCl2, which was obtained by P. Royo et al. from [(C5H4)-SiMe2Cl]TiCl3 either in very low yield by treatment with water in toluene or more rationally and in 45% yield with SiPh2(OH)2 and NEts in hexane. The second one is the spiro titanocene derivative (17)2Ti... 

It is important to understand the limitations of these simplified calculations. While we have assumed complete immiscibility, in reality there is some amount, however small, of toluene dissolved in water, and of water in toluene. The assumption of complete immiscibility allows us to calculate the bubble and dew points quite accurately. This simplification, however, may not be appropriate for other calculations. For example, the presence of toluene in drinking water is regulated by EPA to a maximum of i mg/L, corresponding to a mol fraction of approximately 2 x 10 7. If the purpose of the calculation is to determine compliance with regulations, the assumption of complete immiscibility would be inappropriate. An accurate activity coefficient model is needed for this calculation. 

Complementary strategy is based on self-assembly of block copolymers template inorganic nanoparticles in binary solvents medium to form compact unidirectional structure. For instance, Fahmi et al. developed a simple concept whereby water acts as a trigger for morphological changes in water-in-toluene emulsions of... 

Spinel ferrites can be synthesized in microemulsions and inverse micelles. For example, MnFejO nanoparticles with controllable sizes from about 4-15 nm are synthesized through the formation of water-in-toluene inverse micelles with sodium dodecylbenzenesulfonate (NaDBS) as suifactanP. This synthesis starts with a clear aqueous solution consisting of Mn(N03)2 and Fe(NOj)j. A NaDBS aqueous solution is added to the metal salt solution, subsequent addition of a large volume of toluene forms reverse micelles. The volume ratio of water and toluene determines the size of the resulting MoFCjO nanoparticles. 

ILs can be incorporated in the microemulsion formulation as substituents of the polar and nonpolar phases or as surfactants. In recent studies, Koetz and coworkers [103] showed that the role of cosurfactant can also be assumed by an IL in the stabilization of water-in-oil microemulsions. SDS- and CTAB-based water-in-toluene/ pentanol microemulsions have been formulated with the aid of ethyl-methylimidazolium hexylsulfate, [C2mim][CgSOJ. Their experimental results showed that replacing water by the IL increases the isotropic phase region of the system. The authors assume the formation of a palisade layer (Scheme 13.4), where the IL plays a similar role like a cosmfactant, changes the spontaneous curvature of the interfacial film, and decreases the droplet size. 

The effects of various organoaluminum compounds on ethylene oligomerization with Ni-ylide were evaluated in toluene solution at 30-120°C and ethylene at pressure 6.6—14.6 atm. An excess of AlEtj (20 1) reduces Ni-ylide to Ni(0) under these conditions, resulting in a complete loss of oligomerization activity. Tetraethylaluminoxane (produced in the reaction between AlEt3 and water in toluene solution) also deactivates Ni-ylide in ethylene oligomerization. 

The hydrophobic or hydrophilic nature of the solid and the liquid can dictate the shape and contact angle of the droplet. In practice, hydrophobic solids will have high interfacial surface tensions with aqueous droplets and smaller contact angles, resulting in droplets with a more spherical shape. Conversely, droplets formed on hydrophilic surfaces will be flatter, with a larger contact angle, due to the low interfacial tension between hydrophilic surfaces and the droplet. Gelot et al. [49] found that carbon black, which is hydrophobic, promoted formation of W/0 (water-in-toluene) emulsions. 

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