Toluene five solutes

Toluene Standard Solutions Prepare five working standard solutions with concentrations of 10, 50, 100, 250, and 500 pg/mL by quantitatively diluting Toluene Stock Solution with methanol. 

The most recent, and probably most elegant, process for the asymmetric synthesis of (+)-estrone appHes a tandem Claisen rearrangement and intramolecular ene-reaction (Eig. 23). StereochemicaHy pure (185) is synthesized from (2R)-l,2-0-isopropyhdene-3-butanone in an overall yield of 86% in four chemical steps. Heating a toluene solution of (185), enol ether (187), and 2,6-dimethylphenol to 180°C in a sealed tube for 60 h produces (190) in 76% yield after purification. Ozonolysis of (190) followed by base-catalyzed epimerization of the C8a-hydrogen to a C8P-hydrogen (again similar to conversion of (175) to (176)) produces (184) in 46% yield from (190). Aldehyde (184) was converted to 9,11-dehydroestrone methyl ether (177) as discussed above. The overall yield of 9,11-dehydroestrone methyl ether (177) was 17% in five steps from 6-methoxy-l-tetralone (186) and (185) (201). 

Hydrolysis of the ester is achieved by refluxing in aqueous N or 2N NaOH solution until the insoluble ester dissolves. The solution is then cooled, and the alcohol is extracted into a suitable solvent, e.g. ether, toluene or alcohol-free chloroform. The extract is dried (CaS04, MgS04) and distilled, then fractionally distilled if liquid or recrystallised if solid. (The p-nitrobenzoic acid can be recovered by acidification of the aqueous layer.) In most cases where the alcohol to be purified can be readily extracted fi-om ethanol, the hydrolysis of the ester is best achieved with N or 2N ethanolic NaOH or 85% aqueous ethanolic N NaOH. The former is prepared by dissolving the necessary alkali in a minimum volume of water and diluting with absolute alcohol. The ethanolic solution is refluxed for one to two hours and hydrolysis is complete when an aliquot gives a clear solution on dilution with four or five times its volume of water. The bulk of the ethanol is distilled off and the residue is... 

The original scientific account of the preparation of this body stated that mcfa-isohutyl toluene was heated on a water-bath for twenty-four hours, with five times its weight of a mixture of sulphuric and nitric acids. The product was subjected to a repetition of the same treatment, so as to convert it into trinitro-butyl toluene, which crystallises from alcohol in white needles melting at 96° to 97°. It is insoluble in water, but soluble in organic solvents. Even in very dilute solutions this compound has a. 

A stream of ethylene oxide is passed through a solution of 107 g of 2-(p-chlorophenoxy)-2-methylpropionic acid and 2 g of zinc chloride in 200 ml of toluene, previously heated to between 55°C and 60°C, until 24 g of the gas have been dissolved. The reaction is allowed to continue for five hours, with gentle stirring. After this time has elapsed, the solution is cooled and washed successively with water, dilute ammonia and water until its pH becomes neutral. It is dried over anhydrous sodium sulfate, the solvent Is separated off under vacuum, and the resulting liquid is the monoglycol ester of 2-(p-chlorophenoxv)-2-methylpropionlc acid. 

Now, starting with 0.05 mL toluene, repeat the procedure to obtain five working solutions l -5 and use solution 5 to plot the absorption curve of toluene again record the Amax values for the peaks of the curve. There is a well-developed peak at approximately 270 nm, and using the five test solutions, measure the absorbance of each at the observed peak wavelength and test the application of Beer s Law. Measure solution 5 also at the wavelength used for benzene, and solution 5 at the wavelength used for toluene. 

General procedures for the synthesis of ligands and metal complexes are shown in Scheme 1. For file synthesis of 2a acenaphthenequinone (0.38 g, 2.1 mmol) and a,a-bis(4-amino-3,5-dimethylphenyl)-toluene(Kccess) were dissolved in 50 mL of CH3OH in a round-bottom flask. Five drops of formic acid were added, and the sealed solution was stirred at 50 C overnight. After filtration, the red solid was washed with hot methanol and dried to give 1.2 g of red powder in 50 % yield. 

Silica Alkylation. To tetiamethyldisihzane (TMDS, 1.0 g) in anhydrous toluene (30 mL), amine-functionalized silica was added and stirred overnight at room temperature under N2. Then it was then filtered, washed with toluene three times, and dried under vacuum at 50°C. Ethanol (190 mL) and nanopure water (10 mL) were mixed, and the pH was adjusted to 4.7 with acetic acid. Isobutyltrimethoxysilane (4.0 mL) was added to the solution, stirred for five minutes, and the modified silica was added. After 10 minutes, the solution was decanted, the... 

Starch Indicator. Five grams of soluble starch were dissolved in 1 liter of distilled water. A few drops of toluene were placed on top of the solution as a preservative. 

The in situ bioremediation application at this site included injection of a liquid microbial solution into the subsurface through monitoring and injection wells. This solution includes microbes (Pseudomonas, Bacillus, and Corynebacterium), oxygen, emulsifier, surfactant, and nutrients. Five injections were conducted. Over 11.3 m3 (3000 gallons) was injected from February 1999 to September 2000 into approximately 40 wells and 15 Geoprobe injection points. As of September 2000, MTBE levels decreased by 96% (3310-146 pg/L), while benzene decreased by 83% (2571— 435 pg/L), toluene by 66% (24,330-8300 pg/L), and naphthalene by 84% (5377-853 pg/L) xylene levels increased and were above preoperational level as of September 2000. The system will continue to be operated until all target levels have been met. The total cost for the cleanup of this site is USD63,500.34... 

Complex 12 was found to be a good reactant in the double-silylation reaction. Thus, thermolysis of a toluene solution of 12 and diphenylacetylene at 120°C for 12 h afforded 5,6-carboranylene-1,1,4,4-tetramethyl-2,3-diphenyl-1,4-disilacyclohex-2-ene 13. When 1-hexyne was employed in the reaction with 12 under the same reaction conditions, the five-membered disila ring compound 18 was isolated. A key feature in the h NMR spectrum of 18 includes a singlet at 6.24 ppm assigned to the vinyl proton. A characteristic high-frequency 13C NMR resonance at 138.50ppm provides evidence for a tethered sp2 carbon atom between the two silicon atoms. 

When the mixture has cooled to about 6o°, there are added from the separatory funnel, first, a solution of 114 g. (0.5 mole) of ethyl laurate (Note 3) in 150 cc. of absolute alcohol (Note 4), then 500 cc. more of alcohol, as rapidly as is possible (Note 5) without loss of material through the condenser. The time required for the addition of the ester solution and the alcohol is less than five minutes, usually two or three minutes. When the reaction has subsided, the flask is heated on a steam bath until the sodium is completely dissolved (Note 6). The mixture is then steam distilled to remove the toluene and ethyl alcohol. 

B) Benzyl Carbamate.—A measured aliquot (suitably 10 cc.) of the solution of benzyl chloroformate, prepared as described above, is added slowly and with vigorous stirring to five volumes of cold concentrated ammonium hydroxide (sp. gr. 0.90), and the reaction mixture is allowed to stand at room temperature for thirty minutes. The precipitate is filtered with suction, washed with cold water, and dried in a vacuum desiccator. The yield of practically pure benzyl carbamate, melting at 85-86°, is 7.0-7.2 g. (91-94 per cent of the theoretical amount based on the benzyl alcohol used in. 4). Pure benzyl carbamate melting at 87° is obtained by recrystallizing the slightly impure material from two volumes of toluene. 

C) Carbobenzoxyglycine.—A solution of 7.5 g. (0.1 mole) of glycine in 50 cc. of 2 N sodium hydroxide is placed in a 200-cc. three-necked flask fitted with a mechanical stirrer and two dropping funnels. The flask is cooled in an ice bath, and 17 g. (0.1 mole) of benzyl chloroformate (21-24 g. of the solution obtained in A) and 25 cc. of 4 iV sodium hydroxide are added simultaneously to the vigorously stirred solution over a period of twenty to twenty-five minutes. The mixture is stirred for an additional ten minutes. The toluene layer is separated, and the aqueous... 

In a 2-1. beaker is placed 75 g. (0.4 mole) of 3-bromo-4-amino-toluene (Note 1), and to it is added the hot diluted acid obtained by adding 72 cc. of concentrated sulfuric acid to 200 cc. of water. The clear solution is stirred and cooled to about 15°, after which 180 g. of ice is added the amine sulfate usually separates. As soon as the temperature has dropped below +5°, a solution of 32.2 g. (0.47 mole) of sodium nitrite in 88 cc. of water is added from a dropping funnel, the stem of which extends below the surface of the liquid. The temperature of the solution is kept below +5° during the addition, which requires about fifteen minutes. The solution is stirred for five minutes after the addition of all the sodium nitrite, and 300 g. of cold water, 3 g. of urea, and 300 g. of cracked ice are then added successively. The solution is kept in an ice bath until used. 

A solution of 5 per cent acetaldehyde in toluene is to be extracted with water in a five stage co-current unit. If 25 kg water/100 kg feed is used, what is the mass of acetaldehyde extracted and the final concentration The equilibrium relation is given by ... 

To 23 g Na in 350 ml ethanol add 146 g ethyl-oxalate and 171 g 2-nitro-6-CI-toluene and reflux forty minutes. Dilute the red solution with water and steam distill until no more starting material is distilled. The aqueous residue is filtered, acidified with HC1 and filtered to get 102 g 2-nitro-6-CI-phenylpyruvic acid (I) (recrystallize-benzene). Add 81 g (I) in dilute NH4OH to a solution of 560 g FeS04.7H20 and 230 ml concentrated NH4OH and 2 L water and boil five minutes. Filter, wash precipitate with dilute NH4OH, water and acidify filtrate with dilute HCI to get 60 g 4-CI-2-indole-COOH (11) (recrystallize-aqueous ethanol). 9.78 g (II) and 6.7 g CuCN in 35 g quinoline and reflux (about 237°) for twenty hours. Pour the hot solution into a mixture of 25 ml concentrated HCI and ice. Stir and filter wash precipitate with water and extract the filtrate and precipitate three times with ether. Wash the ether with HCI, water and dry, evaporate in vacuum to get 3.6 g 4-CN-indole (recrystallize-water). Or, heat (II) alone at 290° until fusion then heat at 250° for ten minutes until C02 evolution ceases to get 4-CN-indole. For conversion to 4-formyl-indole see HC A 51,1616(1968). 

In a 3-I. round-bottomed flask fitted with a 3-ft. indented column to which is attached a condenser set for downward distillation are placed 321 g. (3 moles) of methylaniline, 300 g. of formic acid (85-90 per cent), and 1800 cc. of toluene (Note 1). The solution is distilled slowly. As long as the azeotrope containing water is present, the temperature of the vapor is 87-88° when the water has been removed, the temperature rises to 108-110° (Note 2). The distillation is continued until approximately 1500 cc. of toluene has been collected (five to six hours). The residue is then transferred to a modified Claisen flask (Org. Syn. Coll. Vol. 1, 125) and distilled in vacuo, the portion boiling at 114-121° at 8 mm. being collected. This has a freezing point of 13.6-13.7° d i-5S3 I SSS- The yield is 380-393 g. (93-97 per cent of the theoretical amount). This product is satisfactory for the preparation of aldehydes (p. 11). Upon redistillation it boils at 117-121° at 8 mm., 130-132° at 22 mm. The freezing point and refractive index are unchanged. 

The 1,3-dipolar addition reaction of fullerene with diazo compounds is one of the most studied reactions in the early stage of the research on fullerene chemistry [7]. The reaction in solution first affords rather labile fulleropyrazoline derivative 26, which is readily converted to the so-called 5,6-open (a bond originally shared by five- and six-membered rings cleaved) fulleroid (27) or 6,6-closed (a bond shared by two six-membered rings remaining closed) methanofullerene derivatives (28) by heat (e.g., refluxing in toluene) or photoirradiation (UV light), respectively (Scheme 11) [7a]. 

---