Filters suction

Method A. Cool a solution of the nitrate-free dichloride, prepared from or equivalent to 5 0 g. of palladium or platinum, in 50 ml. of water and 5 ml. of concentrated hydrochloric acid in a freezing mixture, and treat it with 50 ml. of formahn (40 per cent, formaldehyde) and 11 g. of the carrier (charcoal or asbestos). Stir the mixture mechanically and add a solution of 50 g. of potassium hydroxide in 50 ml. of water, keeping the temperature below 5°. When the addition is complete, raise the temperature to 60° for 15 minutes. Wash the catalyst thoroughly by decantation with water and finally with dilute acetic acid, collect on a suction filter, and wash with hot water until free from chloride or alkali. Dry at 100° and store in a desiccator. 

B. Extraction with Ether (Note 10).—The solid mixture is transferred to a 2-1. flask and shaken ten minutes with 750 cc. of ether. The ether solution is decanted through a suction filter and the solid thrown onto the filter and pressed dry. The solid is then returned to the flask and shaken with 400 cc. of ether, d his mixture is filtered by suction and the solid washed twice on the filter with 250 cc. portions of ether. Each portion is allowed to drain through the filter several times while the solid is kept... 

To 500 g. (3.85 moles) of freshly distilled ethyl acetoacetate in a i-l. flask set in ice and well cooled, are added 152 g. (2.0 moles) of 40 per cent aqueous formaldehyde solution and 20-25 drops of diethylamine. The flask and contents are kept cold for six hours and are then allowed to stand at room temperature for forty to forty-five hours. At the end of this time two layers are present, a lower oily layer and an upper aqueous layer. The layers are separated, and the aqueous layer is extracted with 50 cc. of ether. The ether solution is added to the oily layer, and the resulting solution is dried over 30 g. of calcium chloride. The ether is then removed by distillation on a steam bath. The residue, amounting to approximately 500 g., is diluted with an equal volume of alcohol and is thoroughly cooled in an ice bath. Ammonia is then passed into the mixture until the solution is saturated. This requires from four to eight hours, and during this time the flask is kept packed in ice. The ammoniacal alcoholic solution is allowed to stand at room temperature for forty to forty-five hours. Most of the alcohol is now evaporated the residue is cooled, and the solid i,4-dihydro-3,5-dicarbethoxy-2,6-dimethylpyridine is removed from the remaining alcohol on a suction filter. The dried ester melts at 175-180 and amounts to 4ro-435 g. (84-89 per cent of the theoretical amount). 

Phenothiazine [92-84-2] M 199.3, m 184-185". Crystd from benzene or toluene (charcoal) after boiling for lOmin under reflux. Filtered on a suction filter. Dried in an oven at 100°, then in a vacuum desiccator over paraffin chips. Also twice recrystd from water and dried in an oven at 100° for 8-lOh. 

The resulting -aminocaproic acid is collected on a suction filter and dried in a desiccator. The yield of -aminocaproic acid melting at 201-203° is 52.5-53.5 g. (90-92 per cent of the theoretical amount). 

The hot reaction mixture is poured with stirring over about 0.75 1. of crushed ice in a 2-1. beaker. The beaker is filled with water, and the mixture is stirred to dissolve inorganic salts (Note 5). The insoluble red-brown solid is collected on a suction filter. This crude product, even while damp, is transferred to a 2-1. round-bottomed flask, and 500 ml. of a mixture of 75% (375 ml.) of petroleum ether (b.p. 90-100°) and 25% (125 ml.) of benzene is added. The flask is provided with a reflux condenser, and the mixture is heated at reflux for 15 minutes by means of an electric mantle (Note 6). The resulting solution is decanted into a second 2-1. flask, leaving in the first flask some water and a red-brown solid residue. Po the slightly cooled liquor in the... 

The product is collected on a suction filter. The yield of air-dried product, as yellow-orange crystals, m.p. 87-89°, is 38-42 g. (65-71%) (Note 8). A purer, lemon-yellow product, m.p. 88.5-90°, is obtained by an additional recrystallization from 1 1. of petroleum ether (b.p. 90-100°) with use of carbon the yield after this second crystallization is 28-34 g. (48-58%). 

Filtrier-erde, /. filtering earth. -flMche, /. filtering surface or area, -flasche, /. filtering flask, -gestell, n. filter stand, -hut, m. (paper) filtering funnel, -kessel, m. filtering boiler, -konus, m. filter cone, -korb, m. filtering basket, -nutsche, /. suction filter, -papier, n. filter paper, -papierstreifen, m. strip of filter paper, -platte, /. filter plate, -presse, /. filter press, -pumpe, /. filter... 

Mikro-nutsche, /. micro suction filter, esp. micro Biichner funnel, -orgamsmen, m.pl. microorganisms. 

Nutschapparat, m. suction filter apparatus. Nutsche, /., -filter, n. suction filter, cap. a Buchner funnel. 

The mother liquorsand washings of fractions I and II are concentrated froma volume of about 1.7 liters to 250 ml, the pH is adjusted to 2.5 with 100% formic acid and the solution is stored overnight in a refrigerator, whereby further substance crystallizes. This is filtered off under suction and washed with a small amount of water. The residue on the suction filter is azeotropically distilled with ethanol. There is obtained solid, almost colorless title substance which is denoted as 8. 8 is purer than A according to thin-layer chromatography. 

After the end of the fermentation (28 hours) the culture broth is filtered off by suction over a large suction filter. The mycel residue is washed with water several times. The filtrate is extracted three times, each time with 10 liters of methyl isobutyl ketone. The extract is concentrated under vacuum in a circulating evaporator and in a round flask carefully dried under vacuum. The residue is crystallized from acetone/isopropyl ether. The melting point is 157°-158°C (fermentation yield = 60%). The pure product yield obtained after a second crystallization and chromatography of the mother liquor on silica gel amounts to 53% of the theoretical. 

The diosmin was precipitated out by adding 120 ml glacial acetic acid and stirring at 70°C for 30 minutes. The precipitate was filtrated in a suction filter or strainer, washed with methanol, water and again methanol and dried at 60°C in the drying cabinet. Raw yield 17.0 g corresponding to 71% yield. Bromine content 0.51%. 

B.5 parts of 1 -azaphenothiazine carboxylic acid chloride and 14 parts of piperidino-ethoxy-ethanol were introduced into 100 parts of chlorobenzene and the mixture boiled under reflux for 5 minutes. After cooling off the precipitated hydrochloride salt of piperidino-ethoxy-ethanol was filtered off on a suction filter. Water was added to the filtrate and the pH thereof adjusted to 5 to 6 with dilute HCI. The aqueous phase was then removed, a caustic soda solution added thereto and then extracted with ether. The ethyl extract waswashed with water, then dried with potash and the ether distilled off. 9.4 parts of the piperidino-ethoxy-ethyi ester of 1 -azaphenothiazine carboxylic acid were obtained. This product was dissolved in 20 parts of isopropanol and the solution neutralized with isopropanolic HCI. The monohydrochloride which precipitated out after recrystallization from isopropanol had a melting point of 160°Cto 161°C. 

Nitrophthalic anhydride (23.5 g, 0.122 mol), urea (3l g, 0.517 mol). CoCl2 (5g, 0.038 mol), and (NH4)2MoO4(0.2 g, 1 mmol) were suspended in PhN02 (130 mL) and healed ai 190 C. After gas evolution had ceased (4-5 h), the mixture was filtered hoi and then washed with PhN02, followed by MeOH. The crude product was boiled for 2 h, first with 1 M HC1 (500 mL) and then with 1 M NaOH (500 mL). filtered, and washed with H20 each time until the filtrate was neutral. The solid material was then stirred in MeOH, suction filtered, and dried in vacuo for 6 h at 60 C yield 18 g (79%). 

A solution of 257 g. (1.05 moles) of barium chloride dihydrate in about 500 cc. of hot water is added to the reaction mixture, with vigorous shaking, and the mixture is heated on a steam bath for one-half hour. A heavy precipitate of the barium salt of the amino acid separates at once. After cooling to room temperature, the barium salt is collected on a suction filter, transferred to a beaker, and washed with two 250-cc. portions of hot water (8o°). After drying at ioo°, the barium salt weighs 225-230 g. (80-82 per cent of the theoretical amount). 

The organotrichlorosilane (100 mmol) was added dropwise to a solution of KF (2.5 mol) in water (220 ml) at 0 C with vigorous stirring. (The reaction is exothermic, and it is essential to maintain the reaction temperature at 0°C.) The organopentafluorosilicate began to precipitate immediately as a white solid. After complete addition, the mixture was stirred at ambient temperature for 2 h to overnight. The precipitate was then suction-filtered. 

The checkers used a sintered glass pressure filter (Coming Glass Works, Cat. No. 34020) rather than a suction filter in order -to minimize evaporation losses. An ordinary water aspirator can cause the mixture to boil at room temperature. The flask and filter can be cleaned readily with a little acetone, which dissolves mercuric bromide rapidly. 

The flask is removed from the oil bath and cooled to room temperature. To the reaction mixture are added successively 21.4 g. (0.12 mole) of finely powdered Nduomosuccininiide (l-bromo-2,5-pyrrolidinedione) (Note 4), 50 ml. of carbon tetrachloride, and 7 drops of aqueous 48% hydrogen bromide (Note 5). The flask is heated at 70 for 10 minutes (Note 6), and the temperature of the bath is then increased to 85° until the color of the reaction becomes light yellow (ca. 1.5 hours Note 7). The reaction mixture is cooled to room temperature, and the carbon tetrachloride and excess thionyl chloride are removed under reduced pressure (Note 8). The residue is suction filtered, and the solid (Note 9) is washed several times with carbon tetrachloride (total 20 ml.) and the combined filtrate collected in a 50-rnl. flask. The solvent is removed from the solution as before, and the residue is distilled into a dry ice-cooled receiver (short-path column) to give, after a small forerun, 16.1-17.1 g. (76-80%) of 2-bromohexanoyl chloride, b.p. 44-47 (1.5 mm.) as a clear, slightly yellow oil, n12 d 1.4707. This material is of sufficient purity for most synthetic purposes (Note 10). 

Water is added to the residue if necessary to make the volume 700 ml., and the solution is treated with 2 g. of Norit and filtered with suction (Note 7). The filtrate is extracted with 100 ml. of ether (which is discarded), and acidified by the addition of 80 ml. of concentrated hydrochloric acid. After thorough chilling, preferably overnight in a refrigerator, the precipitated atrolactic acid is collected on a suction filter (Note 8) and air-dried at a temperature not exceeding 65°. 

B. m-Nitrobenzazide. In a 2-1. round-bottomed flask fitted with an efficient mechanical stirrer is placed a solution of 78 g. (1.2 moles) of commercial sodium azide in 500 ml. of water (Note 3). The flask is surrounded by a water bath kept at 20-25°. The stirrer is started, and over a period of about 1 hour a solution of 185.5 g. (1 mole) of m-nitrobenzoyl chloride in 300 ml. of acetone (previously dried over anhydrous potassium carbonate) is added from a dropping funnel. wz-Nitrobenzazide separates at once as a white precipitate. Stirring is continued for 30 minutes after the addition is complete then 500 ml. of water is added and the reaction mixture stirred for an additional 30 minutes. The azide is separated on a suction filter, washed with water, and dried in the air. The yield of crude product, m.p. 68°, is 189 g. (98%) (Note 4). It may be recrystallized from a mixture of equal parts of benzene and ligroin (b.p. 100-140°), when the temperature is kept below 50° (Note 5). The product thus obtained consists of almost colorless crystals, m.p. 68-69° (Note 6), the recovery being 80-90% (Note 7). 

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