Hexane solvent

Both the carboxyl and the mercapto moieties of thioglycolic acid are acidic. Dissociation constants at 25°C are for pR, 3.6 pi, 10.5. ThioglycoHc acid is miscible ia water, ether, chloroform, dichloroethane and esters. It is weakly soluble ia aHphatic hydrocarbons such as heptane, hexane. Solvents such as alcohols and ketones can also react with thioglycolic acid. 

Liquid—hquid extraction can be used to obtain high purity linoleic acid from safflower fatty acids or linoleic acid from linseed fatty acids using furfural and hexane as solvents (18). High purity linoleic acid has been obtained from sunflower fatty acids using a dimethylformamide and hexane solvent system (19). 

Alumina was purchased from Macherey, Nagel and Co., Diiren (FRG). The checkers employed 650 g of neutral alumina (Fisher, adsorption grade, 80-200 mesh) packed in a 40-cm high column. Yellow impurities remained on the column, while the blue azulene came off with the hexane solvent front. 

The hexane solvent was removed from a solution of DIB AL (22 mmol, 1 Min hexane) at reduced pressure and at ambient temperature, and ether (10 ml) was introduced. l-Cyclohexyl-2-trimethylsilylethyne (20 mmol) was added at such a rate as to maintain ambient temperature within the reaction, and. after 15 min, the reaction flask was placed in a preheated (40 °C) bath for I h. The resulting clear solution was transferred by means of a double-ended syringe to a vigorously stirred cold solution of HC1 (50 ml, 10%). The flask was rinsed with ether (20 ml), and the mixture was stirred until the resulting phases were almost clear. The layers were separated, and the aqueous layer was extracted with ether (40 ml). The combined organic extracts were washed successively with dilute HC1 (20%), saturated sodium hydrogen carbonate solution and brine, and dried. 

A pilot scale plant, incorporating a three litre continuous stirred tank reactor, was used for an investigation into the n-butyl lithium initiated, anionic polymerization of butadiene in n-hexane solvent. The rig was capable of being operated at elevated temperatures and pressures, comparable with industrial operating conditions. 

Hand rinsings Rinsing of hands twice with hexane solvent volume reduction fractionation and clean-up on Florisal GC/ECD No data No data Kazen et al. 1974... 

We investigated lipase-catalyzed acylation of 1-phenylethanol in the presence of various additives, in particular an E. additive using diisopropyl ether as solvent. Enhanced enantioselectivity was obtained when a BEG-hased novel IE, i.e., imidazolium polyoxyethylene(lO) cetyl sulfate, was added at 3-10 mol% vs. substrate in the Burkholderia cepacia lipase (hpase PS-C) catalyzed transesterification using vinyl acetate in diisopropyl ether or a hexane solvent system. ... 

High-performance liquid chromatography (HPLC) with a micellar mobile phase or with a selective pre-column or reaction detection system has also been used to determine alkylenebis(dithiocarbamaes). ° Zineb and mancozeb residues in feed were determined by ion-pair HPLC with ultraviolet (UV) detection at 272 nm. These compounds were converted to water-soluble sodium salts with ethylenediaminetetra-acetic acid (EDTA) and sodium hydroxide. The extracts were ion-pair methylated with tetrabuthylammonium hydrogensulfate (ion-pair reagent) in a chloroform-hexane solvent mixture at pH 6.5-8.S. The use of an electrochemical detector has also been reported. ... 

The adjustment of the pH in the step Hexane Solvent Partitions to pH 7 should be... 

Reactivity ratios for 1-hexene (M ) with 5-methyl-1,4-hexadiene CM2) copolymerization at 30 c in hexane solvent using a Et2AlCl/6-TiCl3 AA catalyst system (Al/Ti atomic ratio s 1.5) were determined. The compositions of copolymers were measured by 300 MHz 1H-NMR spectroscopy. The reactivity ratios, calculated by the Tidwell-Mortimer method, were 1.1 + 0.2 for each of the two monomers. 

The C-NMR spectrum of the hydrogenated polymer sample in CDClj solvent (Figure 8) was identical to that of the polymer we obtained by the direct polymerization of 5-methyl-1-hexene with Et2AlCl/6-TiCl3 AA catalyst (Al/Ti atomic ratio = 1.5, hexane solvent, 30°C). The hydrogenation was essentially complete. 

Pentacarbonyl[phenyl(methoxy)carbene]chromium was prepared by the checkers in 75% yield according to the literature Hegedus, L. S. McGuire, M. A. Schultze, L. M. Org. Synth. 1987, 65,140. This material was stored under nitrogen at -30°C and purified immediately prior to use by filtration through a plug of Celite (hexane solvent). If the chromium carbene is purchased from Aldrich Chemical Company, Inc., the submitters found it was only 65% pure based on capillary GLC analysis. 

Esterification of acetic acid by isopentanol in the presence of Amberlyst-15 [38], Reaction conditions hexane solvent, continuous-flow reactor. 

Mo2(0R)6 compounds in hydrocarbon solvents rapidly polymerize acetylene to a black metallic-looking form of polyacetylene. Propyne is polymerized to a yellow powder, while but-2-yne yields a gelatinous rubber-like material (45). The detailed nature of these polymers is not yet known and the only molybdenum containing compounds recovered from these polymerization reactions were the Mo2(0R)6 compounds. When the reactions were carried out in the presence of pyridine/hexane solvent mixtures, simple adducts Mo2(0R)6(py)2(ac) were isolated for R = i-Pr and CH2-t-Bu, and ac = HCCH, MeCCH and MeCCMe (45,46). 

Similar measurements and analysis have been carried out for the red solution. In this case the concentration of polymer in the chloroform-hexane solvent is limited to less than 4 x 10 r.u./cm. Therefore, the errors for y t and Y"t are larger than in the case of the yellow solution. In addition, the absorption band of the red solution is shifted to the red with respect to that of the yellow solution. Therefore, 2(i)j can only be extended up to 32 000 cm l. 

Semicontinuous polymerization experiments were carried out in a stainless steel enclosure (dry box) under a dry nitrogen atmosphere in three neck flasks (11) equipped with overhead stirrer and an inlet for the continuous introduction of precooled inifer/isobutylene/ solvent feeds to stirred, dilute BCI3/solvent charges. Experiments with binifer were performed at -80°C by the use of CH3Cl/n-hexane solvent mixtures (80/20 v/v), with trinifer at -40°C using CH3CI... 

Semicontinuous Binifer Runs -80°C, CH3Cl/n-hexane solvent mixture ... 

Uncap the vial and add S ml of hexane solvent (1 6 volume/volume ratio) which contain the internal standards. 

Wen and Grutzner used, among other NMR parameters, the QSC of the lithium enolate of acetaldehyde to deduce that it exists as tetramers of different solvation in THF and THF/n-hexane solvent systems . However, the most thorough study of Li QSC and the most interesting in the present context was reported by Jackman and coworkers in 1987167 -pjjg effects on the QSC values of both aggregation and solvation in a number of organolithium systems was studied in this paper, i.e. different arylamides, phenolates, enolates, substituted phenyllithium complexes and lithium phenylacetylide. 

Chronic exposure to commercial hexane solvent (51 % w-hexane) at concentrations up to 9000ppm was not carcinogenic to F-344 rats or to male B6C3F1 mice but did result in an increased incidence of liver tumors in female mice. It is unclear what components of the hexane mixture caused the neoplasms. ... 

Daughtrey W, Newton P, Rhoden R, et ah Chronic inhalation carcinogenicity study of commercial hexane solvent in F-344 rats and B6C3F1 mice. Toxicol Sci 48(l) 21-29, 1999... 

Daughtrey WC, Putman DL, Duffy J, et ah Cytogenetic studies on commercial hexane solvent. J Appl Toxicol 14 161-165, 1994... 

Further illustrations can be seen when the diblock copolymers.of high and medium vinyl are made in hexane solvent. 

The product may be recrystallized from a toluene-hexane solvent mixture described as follows. However, NMR spectra of crude and recrystallized material are identical, so the recrystallization may not be needed for most purposes. The solid is dissolved in several increments of toluene (1 x 20 mL 2x3 mL) by warming to 40° C and the solution is evaporated under reduced pressure to approximately half-volume. Hexane ( 3 mL) is added until the solution becomes cloudy and the solution is then refrigerated overnight. The fine, pale cream crystals of the product are removed by filtration and dried in vacuo. A second crop can be collected by further evaporation of the filtrate and addition of hexane. Yield 0.28-0.32 g (47-62%). 

B. trana-2-Isoayanoeyelohexanol. A 250-mL, one-necked, round-bottomed flask is charged with 13.72 g (70 mmol) of f (t rans-2-isocyanocycl ohexyl )oxy]-trimethylsilane, 12.12 g (210 nmol) of potassium fluoride (Note 7), and 100 mL of methanol. The reaction mixture is stirred magnetically for 5 hr at room temperature (23°C). The methanol is removed under reduced pressure on a rotary evaporator to yield a white slurry. This slurry is added to the top of a 250-g, 60-200 mesh silica gel chromatography column and the column is eluted with 20 ethyl acetate - 80 hexane solvent mixture (Note 8). The solvent is removed from those fractions containing the product under reduced pressure on a rotary evaporator to afford an oil which is redissolved in methylene chloride and the solution is filtered. The methylene chloride is removed from the filtrate under reduced pressure on a rotary evaporator to yield 8.46 g (68 mmol, 97 ) of white, crystalline trans-2-isocyanocyclohexanol, mp 57.0-59.5°C (Note 9). 

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