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Cooling Filtration

Break up cake into small pieces and add to 2.5 liters concentrated NH4OH in 4 liter beaker. Stir. Solid goes into solution and then the sulfonamide precipitates out. Heat to 50°C and then turn off heat. After h hour cool in ice bath and filter. Wash cake with 600 ml water. Add cake to 2 liters 5% NaOH (130 ml 50% NaOH to 2 liters water). Filter and discard insolubles. While cooling filtrate add concentrated HCI until mixture is acid. Filter and wash cake until filtrate is neutral. Suck cake as dry as possible then air dry. Yield approximately 200 g (45%), MP 255° to 260°C. [Pg.1008]

Preparation of Intermediate Compound 2-Methyl-3-o-Tolyl-6-Sulfamyl-7-Chloro-4(3H)-Quinazoiinone Set up a 5-liter 3-necked flask fitted with a stirrer, condenser and a drying tube. To a stirred mixture of 100 g (0.342 mol) of powdered 4-chloro-5-sulfamyl-N-acetylanthranilic acid, 40.2 g (0.376 mol) of o-toluidine and 2.0 liters of dry toluene was added dropwise, over a period of 15 minutes, 21.7 ml (34.1 g) (0.248 mol) of phosphorus trichloride. The mixture was then refluxed for 10 hours. The solid turned somewhat gummy towards the latter part of the first hour. The mixture then became more free flowing as heating was continued. Let stand overnight. The yellow solid was filtered, washed with toluene and dried. The toluene filtrate was discarded. The dried solid was triturated with 1.5 liters of 10% sodium bicarbonate, filtered and the cake washed with water. The filtrate on acidification yielded 11.5 g of the starting acid. The damp product was dissolved in 4,5 liters of 95% ethanol and the solution treated with charcoal and filtered. On cooling filtrate yielded 69.5 g (55.5%) of the title compound, MP 271.5° to 274°C. [Pg.1008]

The resulting white solid is collected on a filter, air dried, redissolved in 2,500 parts water at 95°C and the resulting solution treated with decolorizing charcoal and clarified by filtration. The cooled filtrate is made alkaline with ammonia and the product, crude 3-(1-piperidyl)-Tcyclohexyl-1-phenyl-1-propanol is collected. The hydrochloride melts with decomposition in ten seconds in a bath held at 258.5°C. The alcohol melts at 114.3° to 115.0°C, according to U.S. Patent 2,716,121. [Pg.1542]

The production of heers and ciders requires the fermentation of sugary fluids hy the action of yeasts, and the cooling, filtration, clarification and storage of the resulting alcohol-water mixture. [Pg.198]

Sodium Salt of Eosin.—Grind 6 g. of eosin with 1 g. of anhydrous sodium carbonate, transfer the mixture to a moderate-sized, widenecked, conical flask, moisten with a little alcohol, add 5 c.c. of water, and warm on the water bath until evolution of carbon dioxide ceases. To the aqueous solution of the sodium salt thus obtained now add 20 g. of alcohol, heat to boiling, and filter the hot solution. From the cooled filtrate there separate beautiful brownish-red crystals with metallic lustre, often only after long standing. Collect them at the pump and wash with alcohol. [Pg.327]

HC1 and heat to boiling. If the soln is not clear, filter a portion thru a coarse filter paper, heat ca 100 ml of the clear soln to boiling, and add slowly 10 ml of 50% sulfuric acid. A white ppt indicates barium, which can be confirmed by the grn color obtd in a flame test. Filter and add to the cool filtrate 1 ml of coned HC1. A white ppt indicates the presence of lead... [Pg.1069]

Methyl 4,6-O-benzyIidene-a-D-aItropyranoside. Triturate 4.0 g (0.015 mol) of the foregoing anhydro derivative in a mortar with a solution of 5 g of potassium hydroxide dissolved in 140 ml of water. Transfer the suspension to a round-bottomed flask and heat the mixture under reflux until all the solid has dissolved (about 28 hours). During this period solid material tends to creep up the inside of the flask surface shake periodically to re-suspend material. Remove the trace of insoluble matter which remains and neutralise the cooled filtrate with carbon dioxide (use phenophthalein as an indicator). Extract the solution with five 25 ml portions of dichloromethane, wash the combined extracts with a little cold water, dry over anhydrous sodium sulphate and remove the solvent under reduced pressure (rotary evaporator). Crystallise the syrup by scratching a small portion on a watch glass with ether stir the bulk syrup with ether and the seed crystals. Filter off and recrystallise the product from a small quantity of methanol to obtain 3.5 g (83%) of methyl 4,6-0-benzylidene-oc-D-altropyranoside, m.p. 174 °C, [a]D°+115° (c2 in CHCI3). [Pg.662]

The dried solid was triturated with 1.5 liters of 10% sodium bicarbonate, filtered and the cake washed with water. The filtrate on acidification yielded 11.5 g of the starting acid. The damp product was dissolved in 4.5 liters of 95% ethanol and the solution treated with charcoal and filtered. On cooling filtrate yielded 69.5 g (55.5%) of the title compound, MP 271.5° to 274°C. [Pg.2277]

Alkalies (Free) and Soluble Salts Boil 2 g of sample with 100 mL of water for 5 min in a covered beaker, then filter while hot. Titrate 50 mL of the cooled filtrate with 0.1 A sulfuric acid, using methyl red TS as the indicator. Not more than 2 mL of the acid is consumed. Evaporate 25 mL of the filtrate to dryness, and dry at 105° for 3 h. Not more than 10 mg of residue remains. [Pg.260]

B. Add 95 mL of water to 5 g of sample, and mix (grind coarse grades so a major portion will pass through a 60-mesh screen). Heat to boiling, and filter while hot. Add 1 mL of 1 N sodium hydroxide to 5 mL of cooled filtrate, mix, and allow it to stand at room temperature for 15 min. The formation of a thick, yellow gel indicates the presence of soluble fiber, which dissolves upon the addition of a few drops of 6 A hydrochloric acid. [Pg.459]

C. Mix 1.25 g of a-naphthol with 25 mL of methanol add a few drops of this solution to a test tube containing 5 mL of cooled filtrate from Identification Test B, and mix. Carefully layer sulfuric acid down the side of the test tube. A purple color change occurs at the interface, indicating the presence of residual sucrose. [Pg.459]

A mixture of 50 g. (0.3 mole) of pure anthracene, 30 ml. of oxalyl chloride (p. 242), and 150 ml. of dry nitrobenzene is heated under a reflux condenser in a metal bath. The temperature of the bath is raised from 120° to 240° over a period of 5-6 hours, after which the nitrobenzene is removed by steam distillation. The residue is treated with a solution of 40 g. of sodium hydroxide in 700 ml. of water, and the mixture is heated to reflux for 30 minutes. The mixture is filtered, and the cooled filtrate is extracted with petroleum ether (b.p. 30-60°), after which the aqueous solution is heated to boiling and treated with activated carbon. After filtration of the hot solution to remove the carbon, the carbon is washed with 2 N sodium carbonate solution, and the combined filtrate and washings are acidified to give 41.6 g. (67%) of 9-anthroic acid, m.p. 208-212°,... [Pg.31]

The halogen derivatives of the arsino-compounds are obtained by dissolving the latter in hot glacial acetic acid and adding an excess of the desired sodium halide in solid form. The mixture is heated under reflux for five minutes and the excess of sodium halide filtered off, the cool filtrate depositing a quantitative yield of the halogen compound. [Pg.330]

Na2S03 (anhydrous) with IL of water to ca 90 , shaking until most of the solid had dissolved, then filtering hot. The precipitate obtained by adding lOmL of cone HCl to the cooled filtrate was collected, washed with 95% EtOH until the washings were colourless, and dried under vacuum over CaCl2. It was stored in a dark coloured bottle, in the cold [Chanley, Gindler and Sobotka/Am Chem Soc 74 4347 7952]. [Pg.109]

Mixture of the compounds Me NltCl and MeiNICU separates on cooling. Filtrate then yields pure Me[Pg.173]


See other pages where Cooling Filtration is mentioned: [Pg.216]    [Pg.120]    [Pg.305]    [Pg.109]    [Pg.438]    [Pg.63]    [Pg.10]    [Pg.90]    [Pg.90]    [Pg.813]    [Pg.1114]    [Pg.447]    [Pg.227]    [Pg.243]    [Pg.914]    [Pg.11]    [Pg.315]    [Pg.86]    [Pg.6]    [Pg.241]    [Pg.1006]    [Pg.1848]    [Pg.177]    [Pg.247]    [Pg.168]    [Pg.123]    [Pg.386]    [Pg.340]    [Pg.168]    [Pg.476]    [Pg.230]    [Pg.282]   
See also in sourсe #XX -- [ Pg.419 ]




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