Apolar media

P. Becher, in Interfacial Phenomena in Apolar Media, H. Eicke and G. D. Parfitt, eds., Marcel Dekker, New York, 1987 Nonionic Surfactants Physical Chemistry, M. J. Schick, ed., Marcel Dekker, New York, 1987. 

Luisi, P.L., Straub, B.E. (eds.) Reverse Micelles Biological and Technological Relevance of Amphiphilic Structures in Apolar Media, Plenum, 1984. 

Surfactant Biodegradation Second Edition, Revised and Expanded, R. D. Swisher Nonionic Surfactants Chemical Analysis, edited by John Cross Detergency Theory and Technology, edited by W. Gaie Cutier and Erik Kissa Interfacial Phenomena in Apolar Media, edited by Hans-Friedrich Eicke and Geoffrey... 

The reactions 33 between tetrachloro-A-n-butylphthalimide (113) and n-butylamine275 in aprotic and apolar media (cyclohexane, benzene, toluene, xylenes) show a third experimental reaction order in the amines explained by the formation of a complex (n-jr-like) between the electron acceptor substrate (the derivative of the phthalimide) and the electron donor nucleophile (the amine). In mixed solvents (such as the mixtures cyclohexane/aromatic solvents) the kinetic investigation reveals the presence of a competition between the electron donor solvent and the amine in complexing the substrate. 

We have recently demonstrated the ability of six resorcin[4]arenes and eight water molecules to assemble in apolar media to form a spherical molecular assembly which conforms to a snub cube (Fig. 9.3). [10] The shell consists of 24 asymmetric units - each resorcin[4]arene lies on a four-fold rotation axis and each H2O molecule on a three-fold axis - in which the vertices of the square faces of the polyhedron correspond to the corners of the resorcin[4]arenes and the centroids of the eight triangles that adjoin three squares correspond to the water molecules. The assembly, which exhibits an external diameter of 2.4 nm, possesses an internal volume of about 1.4 A3 and is held together by 60 O-H O hydrogen bonds. 

Using information obtained from X-ray crystallography, we have described the structure of a chiral, spherical molecular assembly held together by 60 hydrogen bonds. [10] The host, which conforms to the structure of a snub cube, self-assembles in apolar media and encapsulates guest species within a cavity that possesses an internal volume of approximately 1.4 nm3. 

O Connor CJ. Interfacial catalysis by microphases in apolar media. Surfactant Sci Ser 1987 21 187-255. 

Eicke HE, Shepherd JCW, Steinemann A (1976) Exchange of Solubilized Water and Aqueous-Electrolyte Solutions between Micelles in Apolar Media. J Colloid Interface Sci 56 168-176... 

Interfacial Phenomena in Apolar Media, edited by Hans-Friedrich Eicke and Geoffrey D. Parfitt... 

Luisi PL, Straub E (1984) Reversed Micelles Biological and technological relevance of amphiphilic structures in apolar media. Plenum, New York... 

Solubilization and Activation. Compounds included in a host lake solubility properties of the host shell, and thus, become more soluble when trapped in polar or apolar media, depending on the nature of the host. This leads to important uses in chemical synthesis known as the phase-transfer principle. 

A milestone in the routine employment of perruthenate in the oxidation of alcohols was established with the publication by Griffith, Ley et al. in 1987 on the catalytic use of tetra- -propylammonium perruthenate (TPAP).11 The presence of the tetra- -propylammonium cation renders this compound soluble in apolar media and allows the existence of a high concentration of perruthenate ion in organic solvents. The tetra- -propylammonium perruthenate is easily prepared and can be employed catalytically in CH2CI2 solution in the oxidation of alcohols to ketones and aldehydes, using /V-methyl morpholine A-oxide (NMO) as the secondary oxidant. 

Christen, H., Eicke, H. F., Rehak, J. Equilibrium considerations of micelle formation in apolar media in the presence of solubilized water. Proc. Intern. Conf. Colloid a. Surface Sci. Vol. 1, p, 481 Wolfram, E. (ed.). Budapest Akademiai Kiado 1975... 

Kelly observed entropy and solvent effects in the first synthetic system that operates as a linear template (Figure 3a) [15]. Specifically, a bifunctional molecule based on a 1,3-disubstituted benzene was found to organize two molecules in apolar media, by way of a N-H N and N-H O forces, for a regiocon-trolled Sn2 reaction. The reaction occurred six times faster than the same reaction without the template. The enhanced rate, however, was significantly less than an analogous intramolecular process. This was attributed, in part, to entropic effects... 

Since the work of Kelly, there have been very few reports that focus upon applications of synthetic linear templates to chemical synthesis. Most recent studies have focused on systems that self-replicate [13]. A synthetic system based on a barbituric acid has been shown to organize two cinnamates in apolar media, by way of N-H N and N-H O forces, for a regiocontrolled [2 + 2] ultraviolet-(UV) induced cycloaddition reaction (Figure 3b) [16]. Similar to the system of Kelly, a mixture of products was attributed to free rotation about C-C bonds of the reactants. 

You may have heard already about carbonic acid molecules being unstable—except in very apolar solvents or in the gas phase. Why is this so You will find the explanation in the topmost line of Figure 8.3. Through proton migration carbonic acid (B) is in equilibrium with the isomeric zwitterion C. This is true, provided that C is sufficiently solvated—which is not the case in very apolar media in which, therefore, the carbonic acid is stable. The zwitterion C eliminates water, much like the second step of an Elcb elimination, and affords C02. It is the... 

This tetrakis-urea was expected to self-assemble in apolar media by hydrogen bond formation between urea moieties of two different units. The analogous behavior of calix[4]arene tetrakis-ureas is well documented [75], but, in contrast to the corresponding calix[4]arene capsules, those deriving from 31 would feature hydrogen bond donor sites within the cavity (Fig. 5). 

Eicke, H. F. Parfitt, G. D., Eds. "Interfacial Phenomena in Apolar Media" Marcel Dekker New York, 1986. 

Recently, the investigations of nitrobenzisoxazoles mainly 6-nitrobenzisoxazole-3-carboxilate ions have received considerable interest due to their participation in reverse micellar systems [679-682], Reverse micelles are of considerable interest as reaction media because they are powerful models for biological compartmental-ization, enzymatic catalysis, and separation of biomolecules. Solutions of ionic surfactants in apolar media may contain reverse micelles, but they may also contain ion pairs or small clusters with water of hydration [679], Molecular design of nonlinear optical organic materials based on 6-nitrobenzoxazole chromophores has been developed [451],... 

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