Fritted-glass funnel

A l-Iiter, three-necked, round-bottom flask is equipped with a mechanical stirrer, a thermometer immersed in the reaction mixture, a dropping funnel, and a gas vent. In the flask is placed a mixture of 96% sulfuric acid (25.5 ml, 470 g, 4.8 mole), carbon tetrachloride (100 ml), and adamantane (13.6 g, 0.10 mole), and the mixture is cooled to 15-20° with rapid stirring in an ice bath. One milliliter of 98% formic acid is added and the mixture is stirred until the evolution of carbon monoxide is rapid (about 5 minutes). A solution of 29.6 g (38 ml, 0.40 mole) of t-butyl alcohol in 55 g (1.2 mole) of 98-100% formic acid is then added dropwise to the stirred mixture over 1-2 hours, the temperature being maintained at 15-20°. After stirring for an additional 30 minutes, the mixture is poured onto 700 g of ice, the layers are separated, and the aqueous (upper) layer is extracted three times with lOO-ml portions of carbon tetrachloride. The combined carbon tetrachloride solutions are shaken with 110 ml of 15 A ammonium hydroxide, whereupon ammonium 1-adamantanecarboxylate forms as a crystalline solid. This precipitate is collected by filtration through a fritted glass funnel and washed... 

The filter pad was prepared by compressing Celite (4 cm) onto a layer of sand (1.5 cm) in a fritted glass funnel (10-cm diameter). 

To a solution of 8 gm (0.05 mole) of 2-amino-3-naphthol (m.p. 225°C) in 100 ml of benzene is added 6 gm (0.05 mole) of thionyl chloride. The mixture is refluxed for 3 hr. The reaction mixture is then cooled and filtered through a fritted-glass funnel. The filtrate is evaporated to dryness to leave 4 gm of an olive-brown residue of the hydroxythionylnaphthylamine (yield 30%). 

Note 2 Periodic Acid 0.25M Solution is prepd by dissolving 55 g of G. Frederick Smith Chem Co HgIOB in one liter of distd w, filtering thru a fritted glass funnel any in sol material and storing a filtrate in a dark glass bottle provided with a glass stopper. For standardiza-... 

In gravimetric analysis, the mass of product from a reaction is measured to determine how much unknown was present. Precipitates from gravimetric analyses are collected by filtration, washed, and then dried. Most precipitates are collected in a fritted-glass funnel (also... 

C. 2,3,4,5,6-Penta-O-acetyl-o-gluconyl chloride. Anhydrous 2,3,4,5,6-penta-O-acetyl-D-gluconic acid (25 g., 0.062 mole) is shaken with 185 ml. of anhydrous ethyl ether in a 1-1. round-bottomed flask until most of the solid dissolves. Then 15 g. (0.072 mole) of phosphorus pentachloride is added with shaking. The flask is fitted with a calcium chloride drying tube and stored overnight at room temperature. Any solid material is removed by filtration through a fritted-glass funnel into a 1-1. round-... 

Two solutions are prepared (a) 5 g. (0.01 mol) of potassium chromium alum is dissolved in 20 ml. of water and (b) 21 g. of sodium hydroxide (0.50 mol) and 10 g. of bigua-nide sulfate 2-hydratet is dissolved in 50 ml. of water. Solution b is heated to 75°, and solution a is added drop by drop with constant stirring. As each drop strikes the alkaline solution, there is a momentary formation of green chromium hydroxide which dissolves to form a dark red solution. As the reaction progresses, bright red, prismatic crystals separate from the solution. After all of solution a has been added, the mixture is cooled in ice water until no more solid separates. The crystals are filtered on a fritted-glass funnel and washed with 5 ml. of cold water. 

The suspension is allowed to settle. Solids are collected by filtration through a coarse-fritted-glass funnel under slight nitrogen pressure and are washed with tetrahydrofuran. The combined filtrate and washings are collected in a 1-1. round-... 

Various procedures for the purification of specific amine-boranes have been reported.12 Ethylenediamine-bisborane can be purified conveniently by aqueous extraction to remove water-soluble impurities. The crude product obtained from the tetrahydrofuran solution is ground to a fine powder in a mortar and added in small portions, with stirring, to about 75 ml. of water which has been cooled in an ice-water bath. Foaming may occur during this treatment. The white crystalline solid which does not dissolve is collected by filtration through a coarse-fritted-glass funnel and washed several times with small portions of cold water (about 5°C.). The final wash filtrate should be neutral toward pH paper. The product is dried by... 

---