Non-aqueous solvent system

W. L. Jolly and C. J. Hallada, Liquid ammonia. Chap. 1 in T. C. WaDDINGTON (ed.), Non-aqueous Solvent Systems, pp. 1-45, Academic Press, London, 1965. J. C. Thompson, The physical properties of metal solutions in non-aqueous solvents. Chap. 6 in J. Lagowski (ed.). The Chemistry of Non-aqueous Solvents, Vol. 2, pp. 265-317, Academic Press, New York, 1967. J. Jander (ed.). Chemistry in Anhydrous Liquid Ammonia, Wiley, Interscience, New York, 1966, 561 pp. 

In contrast to the above resins, the chelating resin Amberlite IRC-718 is based upon a macroreticular matrix. It is claimed to exhibit superior physical durability and adsorption kinetics when compared to chelating resins derived from gel polymers and should also be superior for use in non-aqueous solvent systems. 

Gurney, R. W. Ionic Processes in Solution. London-New York McGraw Hill 1961. Drago, R. S., Purcell, K. F., in Non-Aqueous Solvent Systems (ed. Waddington, T. C.). London-New York Academic Press 1965. 

Performing a systematic comparison of lipase-catalyzed kinetic resolutions of several seeondaiy aleohols in continuous flow mode (Figure 7) and shake flask batch mode using immobilized and non-mobilized lipases was reported by Csajagi and eo-workers [25]. The results indieated that immobilized as well as lyophilized powder forms of liphases can be effeetively used in eontinuous flow mode kinetie resolutions of raeemic alcohols in non-aqueous solvent systems. The produetivity of the lipases was higher in continuous flow reactors than in batch mode systems, whereas the enantiomer selectivities were similar. 

The following discussions of sol vent effects will pro vide further information (a) T. C. Waddington, Non-Aqueous Solvents, Thomas-Nelson, London, 1969 (b) E. M. Kosower, An Introduction to Physical Organic Chemistry, Wiley, New York, 1968, p. 259 (c) T. C. Waddington, Ed., Non-Aqueous Solvent Systems, Academic, London, 1965 (d) E. S. Amis and J. F. Hinton, Solvent Effects on Chemical Phenomena, Academic, New York, 1973 (e) J. F. Coetzee and C. D. Ritchie, Eds., Solute-Solvent Interactions, Marcel Dekker, New York, 1969 (f) A. J. Parker, Chem. Rev., 69, 1 (1969). 

For most potentiometric measurements, either the saturated calomel reference electrode or the silver/silver chloride reference electrode are used. These electrodes can be made compact, are easily produced, and provide reference potentials that do not vary more than a few mV. The silver/silver chloride electrode also finds application in non-aqueous solutions, although some solvents cause the silver chloride film to become soluble. Some experiments have utilised reference electrodes in non-aqueous solvents that are based on zinc or silver couples. From our own experience, aqueous reference electrodes are as convenient for non-aqueous systems as are any of the prototypes that have been developed to date. When there is a need to exclude water rigorously, double-salt bridges (aqueous/non-aqueous) are a convenient solution. This is true even though they involve a liquid junction between the aqueous electrolyte system and the non-aqueous solvent system of the sample solution. The use of conventional reference electrodes does cause some difficulties if the electrolyte of the reference electrode is insoluble in the sample solution. Hence, the use of a calomel electrode saturated with potassium chloride in conjunction with a sample solution that contains perchlorate ion can cause dramatic measurements due to the precipitation of potassium perchlorate at the junction. Such difficulties normally can be eliminated by using a double junction that inserts another inert electrolyte solution between the reference electrode and the sample solution (e.g., a sodium chloride solution). 

Waddington, T. C. (ed.) (1965) Non-Aqueous Solvent Systems, Academic Press, London. 

There are two areas in which it seems that substantial advances could be made even on the basis of first-order theory. These are the field of spontaneous reactions where isotope effects are sometimes large and where the existence of many closely related systems makes it likely that a useful framework of generalizations could be found. The second field is that of strictly non-aqueous solvent systems where a comparison of solvent isotope efFects with those in aqueous solution is likely to throw light on essential differences in chemistry. 

Chariot, G., Tremillon, B. Chemical reactions in solvents and melts (1963) translated by Harvey, P. J. J., Oxford Pergamon Press 1969 3 Waddington, T. C. Non-aqueous solvent systems. New York Academic Press 1965 4 Dawson, L. R. in Chemie in nichtwafirigen ionisierenden Losungsmitteln (ed. G. Jander, H. Spandau, C. C. Addison). Vol. 4, Part 5. New York Interscience 1963, p. 257... 

Tetraalkylammonium salts are the most common electrolytes for the non-aqueous solvent systems and high molecular weight ammoniums have been used for the ion-pair extractant. The thermodynamic properties of the salts such as partition equilibria, solubility, ion-pair formation etc. have been studied in a variety of solvents. The detailed equilibria or structure of ion pair, however, are not fully elucidated. 

For most solutes, the effective hydrogen-bond basicity is constant over all the solvent systems however, in the case of some specific solutes, including anilines and pyri-dines, the effective solute hydrogen-bond basicity varies with the solvent system. Therefore, the descriptors Pj is preferably used for partition between water and non-aqueous solvent systems, while an alternatives P2 can be used for partition between water and aqueous solvent systems [Abraham and Rafols, 1995]. 

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