Tetrahexylammonium

Hg. Allylmercury bromide and diallylmercury are both stable in water. They can allylate aldehydes in aqueous media but, in the case of allylmercury bromide, activation with tetrahexylammonium bromide was necessary.186 The allylation reaction is chemoselective towards aldehyde on the contrary, ketone compounds are unaffected. 

The influence of hydration on the reactivity of anions is much more evident in the case of OH. In the chlorobenzene-aqueous NaOH system the hydration sphere of tetrahexylammonium hydroxide dissolved in the organic phase progressively decreases from 11 to 3.3 water molecules when the base concentration is raised from 15 to 63%. This leads to an enhanced reactivity of OH which was measured in the Hofmann elimination (Equation 3). In the examined ranges of NaOH concentrations the reactivity increased up to more than four orders of magnitude (Table I). Although the dehydration of OH is... 

For example, in our recent study of the tetrahexylammonium dihexyl-sulfosuccinate IL (ILs comprising dihexylsulfosuccinate anion were first synthesized by Kakiuchi et al. [21]) we found that its properties are quite different from those of [C4CiIm][PFg] and other conventional imidazolium ILs. In particular, it is a much more efficient solvent for polar compounds, and if also demonstrates different pH-profiles of extraction [22]. 

Egorov, V.M., Samoylov, VYu., Smirnova, S.V, Petrov, S.I., Pletnev, I.V, Extraction of phenols and amines into new ionic liquid tetrahexylammonium dihexyl-sulfosuccinate, Proc. Int. Conf, Green Solvents for Processes, October 8-11, 2006. Friedrichshafen, Germany, p. 123. 

Several examples of the use of microelectrodes in highly resistive media exist. The first reported measurements were an examination of the reduction of aromatic hydrocarbons such as perylene in benzene containing tetrahexylammonium perchlorate [57]. Although this electrolyte is presumably in a quite associated state in benzene (or toluene [58]), it does impart sufficient conductivity for electrochemistry to be observed. In subsequent work, this result was confirmed and extended to other low-dielectric-constant solvents [59]. Even voltammetry in hexane has been shown to be possible with a microelectrode [60]. In this sol-... 

With tetrahexylammonium as the cation of choice and 5 as ligand, the established conditions for the alkylation with carbon nucleophiles has been successfully applied to asymmetric introduction of heteroatoms such as nitrogen, oxygen, and sulfur (Eq. 8E.7), As shown in Table 8E.8, excellent enantioselectivities are observed independent of the counterion of the heteroatom nucleophiles and the ring size. 

The last entry of table 1, tetrahexylammonium benzoate, is an example of the use of molten salts as electrolytes. In this particular case, the salt is liquid at room temperature, but it has been reported that tetrabutylammonium nitrate at 150° can be used for polarographic and preparative work 7Sa-> (oxidation of polycyclic aromatic hydrocarbons). The use of molten salts as SSE s is of great interest because of the high conductivities of such media as compared to conventional SSE s and deserves further studies. 

Figure 8.1 Cyclic voltammetric response in the absence and presence of thioglycol-capped CdS Q-particles (1 mg/mL of fraction IV) at a Pt electrode. 50 mM tetrahexylammonium perchlorate in DMF, sweep rate = 50 mV s 1. Cl, C2, and C3 refer to cathodic peaks 1, 2, and 3, respectively. Al, A2, and A3 refer to anodic peaks 1, 2, and 3 respectively.8 (Reprinted with permission from S. K. Haram et al.,...

Neumann and Cohen (370) reported the sorption of neutral W catalysts such as Q3PW4O24 (Q = tetrahexylammonium) in supported polyether phases (370). The catalyst (15) consists of polyoxyethylene or polyoxypropy-lene tails, which are covalently bound to a silica surface. The authors claimed an unchanged activity upon reuse of the catalyst. 

The final analytical method for the simultaneous determination of A9-THC and its metabolites consists of the following sequence the cannabinoids are extracted from plasma with toluene they are then back extracted from toluene into Claisen s alkali the Claisen s alkali is diluted with water, tetrahexyl ammonium hydroxide is added and the alkaline solution is extracted with methylene chloride containing ethyl iodide. The overall recoveries were 45% for A9-THC and 83% for 11-hydroxy-A9-THC. External standards (l-0-ethyl-A9-THC and l-0-ethyl-ll-hydroxy-A9-THC) were added to the methylene chloride phase followed by a small amount of Florosil, which absorbed the tetra-hexylammonium hydroxide and tetrahexylammonium iodide. The methylene chloride was decanted and evaporated. 

Note that neat tetrahexylammonium benzoate (SSE no. 41, Table 4) has a reported anodic limit of about 0-3 V versus SCE. This value is, however, given for currents of the order of JUA and cannot be taken as the discharge potential for benzoate ion. Even traces of impurities might interfere at this current level, bearing in mind that the benzoate ion concentration is about 2 M. 

The reduction of tellurium and the alkylation of telluride was carried out in one step using tetrabutylammonium borohydride in refluxing toluene. Dibutyl tellurium was obtained in 95% yield. With tetraethyl-, tetrapropyl-, and tetrahexylammonium borohydride, no reaction occurred2. 

Bis[tetrahexylammonium] letramethylenetetrafluorotellurate(IV) was prepared by treating the tetraiodo compound with an aqueous suspension of silver oxide. The resulting solution was neutralized with hydrofluoric acid2. 

Figure 15.6 Relationship between Jsc and viscosity of the redox medium containing 0.9 M DMHi-i, 50 mM iodine. Organic soivents AN acetonitrile MPN methoxypropionitrile NMO N-methyloxazoiidinone TMS sulfolane. Ionic liquids EMI 1-ethyl-3-methylimidazoHum TMPA trimethylpropylammonium, THA tetrahexylammonium, HMI-I l-hexyl-3-methyl-imidazoHum-iodide, TFSI bis(trifluoromethyl-sulfonyl)imide [21]. (Reprinted by permission of the Publisher, The Electrochemical Society of Japan).

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