Sulfonated naphthalene relative effects

Salts of diazonium ions with certain arenesulfonate ions also have a relatively high stability in the solid state. They are also used for inhibiting the decomposition of diazonium ions in solution. The most recent experimental data (Roller and Zollinger, 1970 Kampar et al., 1977) point to the formation of molecular complexes of the diazonium ions with the arenesulfonates rather than to diazosulfonates (ArN2 —0S02Ar ) as previously thought. For a diazonium ion in acetic acid/water (4 1) solutions of naphthalene derivatives, the complex equilibrium constants are found to increase in the order naphthalene < 1-methylnaphthalene < naphthalene-1-sulfonic acid < 1-naphthylmethanesulfonic acid. The sequence reflects the combined effects of the electron donor properties of these compounds and the Coulomb attraction between the diazonium cation and the sulfonate anions (where present). Arenediazonium salt solutions are also stabilized by crown ethers (see Sec. 11.2). 

The dye l-Anilino 8-Naphthalene Sulfonic acid (ANS) has high specificity for protein. It fluoresces only when bound to protein [30]. In smears and handsections (i.e. unembedded materials) we have never observed it to effect emulsion stability in the manner more traditional protein dyes such as Coomassie Brilliant Blue or Fast Green often do. This relative pH independence probably is due to the mode of action of this dye. It becomes fluorescent in hydrophobic pockets on protein molecules [30] in contrast to the ionic bonding necessary for Fast Green FCF and Coommassie Blue [22]. We have not observed a strong cross-reaction with lipids, either, although a fluorescence of different spectral characteristics sometimes is seen. 

The difference is ascribed to the smaller micelle cavity of succinimides relative to sulfonates. Mixed micelles of naphthalene-sulfonate-succinimide show weaker solubilization capacity than that of individual additives. The solubilization of water in a micellar system is closely related to the micelle core (Fontana, 1968). Addition of water to this non-polar solution, as engine lubricating oil is, produces a new set of phenomena. For small amounts of water, the micellar aggregates show swelling by uptake of water. The highly bounded water in reversed micelles makes surfactants less effective. 

The addition of organic modifiers can produce somewhat drastic effects upon the partitioning equilibria of both ions and ion pairs and hence upon the relative capacity ratio of the solute components. Variation of the concentration of 1-pentanol in chloroform as the mobile phase during the separation of alkylam-monium ions with naphthalene 2-sulfonate as the counter ion proved to be a powerful tactic in enhancing resolution (70). Increasing the ionic strength too much leads to reduced retention of the solute as the added ions compete with the solute for pairing sites (210). 

The discovery that the sulfonation of anthraquinone, which normally occurs in the /3-position, is directed exclusively to the a-position by a small amount of mercury has prompted investigations of the effect of mercury on other sulfonations. No instances have been found in which the course of the reaction of hydrocarbons is altered drastically. The sulfonation of naphthalene and of anthracene is unaffected. However, the course of the reaction of sulfur trioxide-sulfuric acid with o-xylene, o-dichlorobenzene, and o-dibromobenzene is affected to a certain extent. The 4-sulfonic acid is the exclusive product of sulfonation in the absence of mercury the 3-sulfonic acid is formed to the extent of 20-25% in the presence of 10% of mercury. The relative ineffectiveness of mercury in the sulfonation of hydrocarbons is understandable if it is true that the activity of mercury in the reactions of oxygen-containing compounds is due to mercuration followed by replacement with the sulfonic acid grouping. Phenols are known to be particularly susceptible to mercuration (in the ortho position), and mercury has been found to exert some effect in the sulfonation of phenols, such as a-naphthol. ... 

Traditional concrete water reducers are formed by mixing lignin as main component with naphthalene sulfonic acid sodium salt. Although the cost of such kind of additives is relatively low, they cannot provide desirable concrete water reduction when the effective content in the concrete is low. For example, when a type F water reducer, which consists mainly of naphthalene-based compoimds, is used, rapid concrete slump will result. 

---