Ambient-temperature extraction

Traditionally a tincture is an ambient temperature extract that is made with a high alcohol level in the extraction liquid, typically 60-70% or more. The herb/extract ratio is usually 1 part dried herb to 10 parts tincture, although a few tinctures were specified at stronger ratios (i.e. more herb) in the British Pharmaceutical Codex and British Pharmacopoeia. 

A solution containing butylamidine hydrochloride (37.9 g) and K2CO3 (8.4 g) dissolved in 1,4-dioxane were to refluxed and the product from Step 2 (3.7 g) dissolved in 1,4-dioxane added. The mixture refluxed 2 hours, cooled to ambient temperature, extracted with EtOAc, washed with water, brine, dried, and concentrated. The crude product was dissolved in toluene and extracted with 10% aqueous NaOH. The solution was acidified to pH 5.0 with 10% HCl and extracted with EtOAc. The solution was concentrated, acidified using ethyl alcohol saturated with hydrochloric acid, and the solvent removed in vacuo. The residue was recrystallized from ethyl alcohol/diethyl ether and 3.1 g product isolated. H-NMR and MS data supplied. 

On the same time, the simple, reliable and reproducible HPLC and extraction methods were developed for the analysis of tadalafil in pharmaceutical preparation [30]. The column used was monolithic silica column, Chromolith Performance RP-18e (100 mm x 4.6 mm, i.d.). The mobile phase used was phosphate buffer (100 mM, pH 3.0)-acetonitrile (80 20,v/v)at the flow rate of 5 mL / min with LTV detection at 230 nm at ambient temperature. Extraction of tadalafil from tablet was carried out using methanol. Linearity was observed in the concentration range from 100 to 5000 ng/mL for tadalafil with a correlation coefficient (R2) 0.9999 and 100 ng/mL as the limit of detection. The values of linearity range, correlation coefficient (R2) and limit of detection were 50-5000 ng/mL, 0.9999-50 ng/mL, respectively for sildenafil. Parameters of validation prove the precision of the method and its applicability for the determination of tadalafil in pharmaceutical tablet formulation. The method is suitable for high throughput analysis of the drug. 

Ambient-Temperature Extraction of Hydrocarbons From Marine Sediment-Comparison with Boiling-Solvent Extractions... 

Proctor, A and Bowen, D (1996) Ambient-temperature extraction of rice bran oil with hexane and isopropanol. J. Am. Oil Chem. Soc., 73, 811-813. 

Volatility is one of the most important properties of a hydrocarbon solvent. Volatility has a direct relation to the time it takes to evaporate the solvent and, therefore, to the drying time for the dissolved product. The desired value of volatility varies greatly with the nature of the dissolved product and its application temperature. Therefore, whether it be an ink that needs to dry at ambient temperature, sometimes very fast, or whether it be an extraction solvent, the volatility needs are not the same. 

To a suspension of AICI3 (89 g, 0.67 mol) in 1,2-dichloroethane (600 ml) chloroacctyl chloride (56ml, 0.70mol) was added dropwise at 0°C. After the addition was complete the mixture was kept at ambient temperature for 15 min, at which lime l-(2,2-dimethylpropanoyl)indole (30 g, 0.15 mol) was added over 3 h. After completion of the addition, the mixture was stirred for 15 min and then poured into ice-cold water. The mixture was extracted with 1,2-dichloroethane. The extract was washed with water (3 x) and aq. 5% NaHCOj (3 X), dried (Na2S04) and concentrated in vacuo. The residue was... 

Phase Separation. Microporous polymer systems consisting of essentially spherical, intercoimected voids, with a narrow range of pore and ceU-size distribution have been produced from a variety of thermoplastic resins by the phase-separation technique (127). If a polyolefin or polystyrene is insoluble in a solvent at low temperature but soluble at high temperatures, the solvent can be used to prepare a microporous polymer. When the solutions, containing 10—70% polymer, are cooled to ambient temperatures, the polymer separates as a second phase. The remaining nonsolvent can then be extracted from the solid material with common organic solvents. These microporous polymers may be useful in microfiltrations or as controlled-release carriers for a variety of chemicals. 

Among the properties sought in the solvent are low cost, avadabihty, stabiUty, low volatiUty at ambient temperature, limited miscibility in aqueous systems present in the process, no solvent capacity for the salts, good solvent capacity for the acids, and sufficient difference in distribution coefficient of the two acids to permit their separation in the solvent-extraction operation. Practical solvents are C, C, and alcohols. For industrial process, alcohols are the best choice (see Amyl alcohols). Small quantities of potassium nitrate continue to be produced from natural sources, eg, the caUche deposits in Chile. 

FoodApphca.tlons, Carbon dioxide, a nontoxic material, can be used to extract thermally labde food components at near-ambient temperatures. The food product is thus not contaminated with residual solvent, as is potentially the case when usiag coaveatioaal Hquid solveats such as methylene chloride or hexane. In the food iadustry, CO2 is not recorded as a foreign substance or additive. Supercritical solvents not only can remove oils, caffeiae, or cholesterol from food substrates, but can also be used to fractionate mixtures such as glycerides and vegetable oils iato aumerous compoaeats. 

An hplc assay was developed suitable for the analysis of enantiomers of ketoprofen (KT), a 2-arylpropionic acid nonsteroidal antiinflammatory dmg (NSAID), in plasma and urine (59). Following the addition of racemic fenprofen as internal standard (IS), plasma containing the KT enantiomers and IS was extracted by Hquid-Hquid extraction at an acidic pH. After evaporation of the organic layer, the dmg and IS were reconstituted in the mobile phase and injected onto the hplc column. The enantiomers were separated at ambient temperature on a commercially available 250 x 4.6 mm amylose carbamate-packed chiral column (chiral AD) with hexane—isopropyl alcohol—trifluoroacetic acid (80 19.9 0.1) as the mobile phase pumped at 1.0 mL/min. The enantiomers of KT were quantified by uv detection with the wavelength set at 254 nm. The assay allows direct quantitation of KT enantiomers in clinical studies in human plasma and urine after adrninistration of therapeutic doses. 

Chloro-2-(3-methyl-4H-1,2,4-triazol-4-yDbenzophenone (Oxidation of 7solution prepared by adding sodium periodate (2 g) to a stirred suspension of ruthenium dioxide (200 mg) in water (35 ml). The mixture became dark. Additional sodium periodate 18 g) was added during the next 15 minutes. The ice-bath was removed and the mixture was stirred for 45 minutes. Additional sodium periodate (4 g) was added and the mixture was stirred at ambient temperature for 18 hours and filtered. The solid was washed with acetone and the combined filtrate was concentrated in vacuo. The residue was suspended in water and extracted with methylene chloride. The extract was dried over anhydrous potassium carbonate and concentrated. The residue was chromatographed on silica... 

Chloro-1 -methyl-6-phenyl4H-s-triazolo-[4,3-a] [1,4] -benzodiazepine A stirred suspension of 5-chloro-2-[3-(bromomethyl)-5-methyl4H-1,2,4-triazol4-yl] -benzophenone (391 mg, 0.001 mol) in tetrahydrofuran (15 ml) was cooled in an ice-bat hand treated with a saturated solution of ammonia in methanol (12.5 ml). The resulting solution was allowed to warm to ambient temperature and stand for 24 hours. It was then concentrated in vacuo. The residue was suspended in water, treated with a little sodium bicarbonate and extracted with methylene chloride. The extract was washed with brine, dried with anhydrous potassium carbonate and concentrated. The residue was crystallized from methylene chloride-ethyl acetate to give... 

The Product having been allowed to cool to ambient temperature, 200 ml of cold water are added. The Organic phase is separated and extracted with an aqueous solution of hydrochloric acid. 

A suspension of 13.2 g methyl 3-(p-chlorobenzoyl)-3-thioacetylpropionate is agitated in 500 ml of a 2N aqueous solution of KOH for 6 hours at ambient temperature in an atmosphere of nitrogen, followed by extraction with ethyl ether. The aqueous phase, adjusted to a pH equal to 2 with 2N HCI, is extracted with ethyl ether which was washed with water, dried over Na2S04, and finally evaporated to dryness. 

Upon completion of the addition, the mixture is agitated for 7 hours at ambient temperature. The solution is then poured into 3 liters of water/ice obtaining a clear solution of dark yellow color which is rendered alkaline upon phenolphthalein with 30% NaOH and extracted with ethyl ether to eliminate the majority of the pyridine. The mixture is filtered with active charcoal, the pH adjusted to 8 with hydrochloric acid 1 1 and extracted with chloroform to remove the 4,4 -dihydroxydiphenyl-(2-pyridyl)-methane which has not reacted. 

The decanted aqueous phase was extracted three times with a total of 150 ml of ethyl acetate. The combined organic solutions were filtered over Clarcel and extracted three times with a total of 150 ml of an Iced normal aqueous methane-sulfonic acid solution. The combined acid extracts were rendered alkaline on an ice bath with 30 ml of ION caustic soda solution. The separated oil was extracted four times with a total of 200 ml of ether. The combined ethereal extracts were washed twelve times with a totai of 360 ml of distilled water, dried over anhydrous magnesium sulfate in the presence of 0.3 g of animal charcoal and evaporated under reduced pressure on a water bath at 40°C. The oily residue obtained (3.8 g) was dissolved in 30 ml of boiling acetonitrile. After cooling for 2 hours at 3°C, the crystals formed were separated, washed with 5 ml of acetonitrile and dried at ambient temperature at low pressure. 

A solution of 17.22 g of N-ethyl-0(-aminomethylpyrrolidine in 360 ml of pyridine is placed in a 1 8 balloon flask. A solution of 3.51 g of phosphorus trichloride in 40 ml of pyridine is added at ambient temperature. After the mixture has been stirred for 1 hour, 10 g of 2-meth-oxy-5-ethylsulfonylben20ic acid is introduced. The mixture is heated under reflux for 4Vi hours. After cooling, the solvent is evaporated under vacuum and the residue is dissolved in 200 ml of 20% sodium hydroxide. The solution is extracted with 200 ml of chloroform. 

The ketone, preferably prepared by a Grignard reaction, was added in such a way as to maintain the ether under constant reflux. When all of the solution had been added, the mixture was refluxed for a further hour. The mixture was then allowed to stand for 12 hours at ambient temperature, after which the reaction mass was extracted with ice and ammonium chloride in known manner. 

This condition is of concern only when equipment operates in subzero ambient temperatures. Since diesel fuel extracted from crude oil contains a quantity of paraffin wax, at some low ambient temperatures this paraffin will precipitate and create wax crystals in the fuel. This can result in plugging of the fuel filters, resulting in a hard or no-start condition. Any moisture in the fuel can also form ice ciystals. Cloud point temperatures for various grades of diesel and other fuels should be at least 12°C (21.6°F) below the ambient temperature. In cases where cloud point becomes a problem, a fuel water separator and a heater are employed. 

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 solution of hex-l-yne (0.3 mol) in ether (100 ml) was treated consecutively at -78 °C with a solution of n-butyl lithium (0.306 mol) in hexane and with TMSC1 (0.306 mol). The reaction mixture was brought to ambient temperature, stirred for 2h, and then quenched with ice-water. The layers were separated, and the aqueous layer was re-extracted with pentane. The combined organic extracts were washed with water and brine, and dried. Concentration and distillation gave the alkynylsilane (0.267mol, 89%), b.p. 71-73 C/36mmHg. 

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