Chlorides alkylammonium

The main use of these clays is to control, or adjust, viscosity in nonaqueous systems. Organoclays can be dispersed in nonaqueous fluids to modify the viscosity of the fluid so that the fluid exhibits non-Newtonian thixotropic behavior. Important segments of this area are drilling fluids, greases (79,80), lubricants, and oil-based paints. The most used commercial products in this area are dimethyl di (hydrogen a ted tallow) alkylammonium chloride [61789-80-8] dimethyl (hydrogen a ted tallow)aLkylbenzylammonium chloride [61789-72-8] and methyldi(hydrogenated tallow)aLkylbenzylammonium chloride [68391-01-5]. 

Dimethyldiphosphine, 19 20 Dimethylditallow alkylammonium chlorides, function as ingredient in cosmetics, 7 829t Al,Al-Dimethyldodecyl amine oxide, 2 815-816... 

Similarly, N-alkylammonium [28] and alkylphosphonium [29] salts form lamellar phases with smectic bilayer structures. In both cases. X-ray scattering also showed the isotropic liquid not to be completely disordered and still displaying similar features to the mesophase. Buscio et al. [28] showed that in N-alkylammonium chlorides the feature was not only much broader than that observed in the mesophase but increased in width with decreasing chain length. 

The most widely used sensor for chloride ions in clinical analyzers is based on an ion-exchanger, a quaternary alkylammonium chloride, dispersed in a plastic membrane. It is not an ideal sensor due to the interference of lipophilic anions (e.g., salicylates, bromides) and lip-ophylic cations (e.g., bacteriostatic agents, anesthetics) and a relatively poor selectivity towards hydrogen carbonates (bicarbonates). However, compared to charged anion- and neutral carrier-based membranes that have been tested, it is still the best-suited for automated analyzers. 

Excision reactions are sometimes accompanied by redox chemistry. For example, dissolution of the 2D solid Na4Zr6BeCli6 in acetonitrile in the presence of an alkylammonium chloride salt results in simultaneous reduction of the cluster cores (144). Here, the oxidation product remains unidentified, but is presumably the solvent itself. As a means of preventing such redox activity, Hughbanks (6) developed the use of some room temperature molten salts as excision media, specifically with application to centered zirconium-halide cluster phases. A number of these solids have been shown to dissolve in l-ethyl-2-methylimidazolium chloride-aluminum chloride ionic liquids, providing an efficient route to molecular clusters with a full compliments of terminal chloride ligands. Such molten salts are also well suited for electrochemical studies. 

With the use of ammonium chloride instead of alkylammonium chlorides, 4-aryl-3-piperideines unsubstituted at position 1 are obtained.14... 

Benzimidazoles, too, are readily alkylated either in neutral or basic medium. As with the uncondensed compounds, the former conditions are complicated by salt formation, but to a lesser extent since benzimidazoles are less basic. It is often valuable to vary the initial amounts of alkali and alkyl halide in order to improve yields. The best yields of 1-alkylbenzimidazole (76-83% for primary and 50-60% for secondary alkyl and aralkyl bromides) result with two moles of bromide and 1.5 moles of alkali per mole of benzimidazole (66RCRI22). There is severe steric hindrance to the alkylation of 2-arylben-zimidazoles in alkaline medium, but reactions with the silver salts seem more successful. The rapid and almost quantitative reaction between a benzimidazole and dimethylphenyl-alkylammonium chlorides in aqueous sodium hydroxide provides a very convenient method of introducing a primary aralkyl group (benzyl, a-naphthylmethyl). There has been little systematic study of the dkylation of unsymmetrical benzimidazoles, though much the same criteria should apply as in the uncondensed compounds. In this respect the observation that 1-bromopropane reacts with the anion of 2,6-dimethyl-4-nitrobenzimidazole to give... 

Investigation of the mechanism of these reactions has suggested ways in which the yields can be improved. Acidic conditions (pH 2) will prevent Cannizzaro rearrangement of any glyoxal-type species and also serve to hydrolyse any Schiff bases which result from side reactions of aldehyde and amine. Conditions should be adjusted so that the rate of hydrolysis of linear products is equal to the rate of cyclocondensation, allowing accumulation of the imidazole products. From glyoxal, formaldehyde and ammonium chloride the yield of imidazole can be inereased to 85% by careful control of the conditions. With an appropriate alkylammonium chloride, 1-substituted imidazoles are also accessible (e.g. 1-methyl (56%), 1-isopropyl (46%), 1-cyclohexyl (49%), 1-n-butyl (55%), 1-t-butyl (25%)). The process may have some applications, but yields drop off with branched alkyl compounds [22 j. Imidazolium salts are also available under similar conditions when two molar equivalents of a primary alkylamine are used [23]. 

Figure 4.17. Surface tension increments of aqueous solutions of alkylammonium chlorides influence of the chain length. Temperature 25°C. (Redrawn from Tamakl )...

Alkyltrimethylammonium bromides -Alkylammonium chlorides Alumina, Preparation Standardization a-Amino acids... 

Alkylammonium chloride n=2,4,6. Recrystallise them from EtOH or an EtOH/Et20 mixture. 

Empirical Equations Many investigators have developed empirical equations relating the CMC to the various structural units in surface-active agents. Thus, for homologous straight-chain ionic surfactants (soaps, alkanesulfonates, alkyl sulfates, alkylammonium chlorides, alkyltrimethylammonium bromides) in aqueous medium, a relation between the CMC and the number of carbon atoms N in the hydrophobic chain was found (Klevens, 1953) in the form... 

Many empirical equations have been developed relating CMC of surfactants to structural units in them. For homologous straight-chain ionic surfactants (soaps, alkylsul-fonates, alkylsulfates, alkylammonium chlorides and alkyltrimethyl-ammonium bromides) in aqueous medium, the following relationship between CMC and the number of carbon atoms (n) in the hydrophobic chain has been obtained (Somasundaran, 1964 Lin, 1971 Somasundaran and Fuerstenau, 1968 Bolden et al., 1983) ... 

Figure 10-2. Long spacings of n-alkylammonium chlorides in all five polymorphic forms observed at room temperature...

Several alkylammonium chlorides have been analysed using chlorine SSNMR. In 1994, Hattori et al. observed the temperature dependence of the Cl quad-rupolar coupling constant of C4H9NH3CI, which ranged from 0.85 to 1.2 MHz over a temperature range of 300-480 K. In 2003, Honda published a study... 

The use of an alkylammonium chloride in place of NH4CI in reaction 12.58 leads to the formation of an (V-alkyl derivative (C1BNR)3 which can be converted to (HBNR)3 by treatment with Na[BH4]. 

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