Behavior in aqueous solutions

Amine oxides show either nonionic or cationic behavior in aqueous solution depending on pH. In acid solution the cationic form (R2N" OH) is observed (2) while in neutral and alkaline solution the nonionic form predorninates as the hydrate R NO H2O. The formation of an ionic species in the acidic pH range stabilizes the form generated by the most studied commercial amine oxide, dimethyldodecylamine oxide (6). 

Because of their preferential use as detergents, the main interest in the physicochemical properties of the salts of a-sulfo fatty acid esters is related to their behavior in aqueous solution and at interfaces. In principle these are surface-active properties of general interest like micelle formation, solubility, and adsorption, and those of interest for special applications like detergency, foaming, and stability in hard water. 

The two strands of the nucleic acid DNA are held together by four organic bases. The structure of one of these bases, thymine, is shown below, (a) How many protons can this base accept (b) Draw the structure of each conjugate acid that can be formed, (c) Mark with an asterisk any structure that can show amphiprotic behavior in aqueous solution. 

Lewis Acid-Base Behavior in Aqueous Solution Some Implications for Metal Ions in Biology Robert D. Hancock and Arthur E. Martell... 

LEWIS ACID-BASE BEHAVIOR IN AQUEOUS SOLUTION SOME IMPLICATIONS FOR METAL IONS... 

The synthesis of amphilic l.c.-side chain polymers and their phase behavior in aqueous solutions verifies that these polymers exhibit hexagonal, cubic and lamellar phases in analogy to the monomeric systems. 

Since the equilibrium constant for the amine acting as an acid is 10 35 and that for the amine acting as a base is much larger at 10 6, reaction as a base will be the main behavior in aqueous solution. The magnitude of the equilibrium constant (10-6) indicates that it is only a weak base. 

Very recently, a new type of metallomicelle with a zinc(II) cyclen attached to a hexadecyl group, 11, has been synthesized (Scheme 6). An unprecedented clear picture of its catalytic behavior in a comicellar solution with Triton X-100 has been disclosed [28], Since the parent Zn2+—cyclen complex 2 showed discrete behavior in aqueous solution (i.e., no dissociation of the zinc(II) ion stable, discrete monomeric species) [7,13,14], 11 was anticipated to behave in an orderly way, and that turned out to be the case. 

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