1 -hexyl sulfate from

Schmitt and Cagle (170) used an aqueous solution of 1 % sulfuric add and 0.5% surfactant to clean surfaces contaminated with 4,4 -methylene bis(2-chloroaniline) (MOCA). Spraying with an aqueous solution containing 5% tetrapotassium pyrophosphate and 10% sodium ethyl hexyl sulfate was proposed by Hackman and Rust (171) to remove 3,3 -dichlorobenzidine from surfaces, and the washes were further treated by diazotization. Diazotization was also used by Genin (172) to treat industrial effluents containing benzidine. Two similar methods were investigated and are discussed below. 

To a solution of 13.6 g (0.08 mol) of N-hexylpiperazine and 8.1 g (11.2 ml), (0.08 mol) of triethylamine in 120 ml toluene, was added 15.6 g (0.08 mol) of N-isobutyl-benzimidoyl chloride over a period of 15 minutes. The reaction mixture was stirred at room temperature for a period of 2 hours. The triethylamine hydrochloride was filtered off and the filtrate concentrated under vacuum. The residual oily base was washed with 20 ml water, extracted with 50 ml ether and dried over anhydrous magnesium sulfate. The dry ethereal solution was then added to a solution of 18.6 g (0.16 mol) maleic acid in 800 ml ether to obtain the dimaleate salt. Two recrystallizations from ethanol yielded 22.5 g (50.2%) of N-[(4-hexyl-l-piperazinyl)phenylmethylene]-2-methyl-l-propanamine product, M.P. 175°-176°C. 

Fig. 10. Chromatograms illustrating the effect of pairing ions on the separation of the dipeptides Ala-Tyr (1), Pro-Tyr (2), and Leu-Tyr (3) by reversed-phase chromatography. Column /x-Bondapak C flow rate 2 ml/min temperature 20 C eluents A, 5% methanol-95% water-50 mJVf KHjP04-5 mM HjPOi, pH 3.0 B, same as A plus 5 laM n-hexyl sulfonate C, 50% methanol-50% water-50 mW KH1PO4-5 mW HjP04-5 mA/ do-decyl sulfate, pH 3.0. Reprinted with permission from Hearn el al. (29). Copyright by Elsevier Scientific Publishing Co., Amsterdam.

Figure 3.12 Relationships between kf for ejnnephrine and the concentration of alkyl sulfates in the mobile phase taken from the data of Horvath and co-workers. See Horvath (1977b) for experimental details. The curves for butyl-, hexyl- and octylsulfate have been simulated according to equation (3.25) and the following parameters (a) butyl sulfonate = 0.5, k Ax = L 1 = 200 M (b) hexyl sulfonate k - = 0.5, k x = 3, = 200 M (c) hexyl sul-...

Optically active 3-amino-2-hydroxycarboxylic acid derivatives are often key components of medicinally important compounds. The synthesis of isopropyl (2i ,35)-3-amino-4-cyclo-hexyl-2-hydroxybutyrate (126) (Scheme 28) takes advantage of a [2 + 2]-cycloaddition reaction of the chiral imines 123, prepared from 63, to assemble the important diastereomeric azetidinone 124 as the crucial precursor for completion of this novel synthesis. Protection of the hydroxy group of 63 as either the TBS ether 119 or the tert-buty ether 120, followed by a DIBAL reduction at —78 °C, produces smoothly one of the aldehydes 121 or 122. Condensation of these aldehydes with either di-p-anisylmethylamine or benzylamine in the presence of anhydrous magnesium sulfate affords the four possible chiral imines 123a—d (Scheme 26). 

The macrocyclic Schiff base L37 contains an hexyl linker between the two amine groups. In anion transport experiments, the corresponding metal complexes of L37 are found to successfully extract sulfate anion from aqueous solution to organic solvents. In the case of the copper complex of receptor L37, it was found that more than... 

The use of di-(p-alkylphenyl)phosphoric acids containing butyl, hexyl, octyl and nonyl alkyl groups as carriers for separations of Co(II), Cu(II), Ni(II), and Zn(II) from aqueous sulfate solutions by bulk and emulsion liquid membrane processes has been explored. The organic phase was the di-(p-alkylphenyl)phosphoric acid in kerosene widi the inclusion of Span 80 as an emulsifier for the emulsion liquid membrane systems. Both single metal ion species and competitive transport of the transition metal cations were investigated. For comparison, the transport of these metal cations by commercially available Cyanex 272 and D2EHPA as carriers was studied also. To probe the mechanism of the liquid membrane transport processes, interfacial tension measurements were conducted. Multistage emulsion liquid membrane processes for the separation of the transition metal cation mixtures have been evaluated. 

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