System diethylamine-toluene

The effect of temperature on extraction rates was investigated by Morello and Beckmann (58), whose data on the system diethylamine-toluene-water are summarized in Table 10.4. Most of the variation in temperature can be taken care of by inclusion of the distribution coefficient in the correlating... 

Musumarra et al. [43] identified miconazole and other drugs by principal components analysis of standardized thin-layer chromatographic data in four eluent systems. The eluents, ethylacetate methanol 30% ammonium hydroxide (85 10 15), cyclohexane-toluene-diethylamine (65 25 10), ethylacetate chloroform (50 50), and acetone with the plates dipped in potassium hydroxide solution, provided a two-component model that accounts for 73% of the total variance. The scores plot allowed the restriction of the range of inquiry to a few candidates. This result is of great practical significance in analytical toxicology, especially when account is taken of the cost, the time, the analytical instrumentation and the simplicity of the calculations required by the method. 

The observed rates of transfer are lower than those calculated by the correlation of Eq. 26 for organic molecules which themselves are surface-active, without specifically added long-chain molecules thus in the transference of (C4H9)4NI from water to nitrobenzene, of benzoic acid from toluene to water and the reverse, of diethylamine between butyl acetate and water, of n-butanol from water to benzene, and of propionic acid between toluene and water, the rates (44, 4 ) are of the order one-quarter to one-half those calculated by Eqs. (25) and (26). Since with these systems the solute itself is interfacially active, and therefore its monolayers should reduce the transfer of momentum, we interpret these findings as indicative that Ri and R2 are increased in this way. This is... 

Several TLC methods have been described for the identification of isoxsuprine [36]. In all systems, silica gel G, dipped in sodium hydroxide solution or methanol, was used as the stationary phase. Either 100 1.5 methanol strong ammonia, 75 15 10 cyclohexane toluene diethylamine, or 90 10 chloroform methanol was successfully used as the mobile phase. In all systems, the spray reagent used to develop the places was acidified potassium permanganate solution. 

The benzodiazepines are a diverse group of drugs and require a combination of different TLC solvent systems to resolve the many drugs in this group. The systems which have been used include chloroform/acetone (80 20 and 90 10, by volume) and cyclohexane/toluene/diethylamine (75 15 10, by volume). The... 

Toluene-ethyl acetate-diethylamine (70 20 10) Screening system, suitable for the major alkaloids of most drugs... 

Remark Some of the strongly basic alkaloids do not migrate in the screening system A if at the start-line of the chromatogram a positive DRG reaction is shown, a second chromatogram should be run in solvent system toluene-ethyl acetate-diethylamine... 

Quinine is separated from quinidine in normal phase TLC in mobile phases composed of chloroform, acetone, and ethyl acetate to which alcohols such as methanol, propanol, or butanol are added as polarity adjusters and ammonia or diethylamine to reduce spot tailing [43], Common solvent systems used for the separation of cinchona alkaloids include chloroform/diethylamine (90 10, v/v) or toluene/ethyl acetate/diethylamine (70 20 10, v/v/v). After spraying the chromatogram with sulfuric acid, these alkaloids show a blue fluorescence in UV-365 nm. Treatment afterwards with iodoplatinate reagent gives a violet coloration in the visible [53]. 

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