Acetic acid, glacial preparation

Camoy s fixative 75 mL methanol and 25 mL acetic acid (glacial). Prepare 4 mL of fixative for each sample to be tested. NB Care must be taken when disposing of used fixative. 

To prepare pure acetic acid (glacial acetic acid), the crude aqueous product is converted into the sodium salt, the latter dehydrated by fusionf and then heated with concentrated sulphuric acid anhydrous acetic acid, b.p. 118°, distils over. Only the preparation of aqueous acetic acid and of crystalline copper acetate is described below. 

They are usually best obtained by dissolving the aldehyde in alcohol, and adding excess of an equimolecular mixture of semi-carbazide hydrochloride, and acetate of sodium. The mixture is allowed to stand for some time and the ssmi-carbazone then precipitated by the addition of water. Some semi-carbazones are more easily prepared by substituting free acetic acid (glacial) for the acetate of sodium. Semi-carbazones are beat recrystallis from hot methyl alcohol. 

Acetic acid, glacial, dehydration for use in preparation of titanium derivative of acetylacetone, 2 119... 

A 2% solution of natural orcein (Gurr s) in 60% glacial acetic acid is prepared by dissolving the orcein in boiling glacial acetic acid with stirring. Cool to 55 °C. Add distilled water to make the acid 60%. Cool to room temperature. Filter twice through Whatman filter paper No. 1. 

Each vial contains the non radioactive materials necessary to prepare one patient dose, which is a sterile, lyophilized formulation, containing 1.25 mg of Arcitumomab and 0.29 mg of stannous chloride per vial, with potassium sodium tartrate tetrahydrate, sodium acetate trihydrate, sodium chloride, acetic acid, glacial, hydrochloric acid, and sucrose. Technetium Tc 99 m Arcitumomab, is formed by reconstitution of the contents of this vial with 30 mCi of Tc 99 m sodium pertechnetate in 1 mL of sodium chloride for injection, LISP. 

B. Diphenyl Triketone Hydrate A solution of 34.3 g. (0.42 mole) of fused sodium acetate in 142 cc. of hot glacial acetic acid is prepared in a i-l. round-bottomed flask 72.4 g. (0.19 mole) of dibenzoyldibromomethane is added, and the mixture is refluxed until the precipitation of sodium bromide ceases (one and one-half to two hours). The mixture is then cooled to room temperature and diluted with 150-200 cc. of water with constant shaking to dissolve the inorganic salt and to precipitate the triketone hydrate, which separates as a white, curdy mass (Note 4). This is separated by filtration, washed well with water, and dried in an oven at 60°. The melting point varies from 65 to 90°, depending upon the extent of dehydration that occurs during the drying operation. The yield is 41.5 g. (86 per cent of the theoretical amount based on the dibenzoyldibromomethane). 

Why do we have to add glacial acetic acid in preparing a clear solution of Cu(II) acetate in water ... 

Carter, H. E., and C. M. Stevens Azlactone Formation in Glacial and in Aqueous Acetic Acid and Preparation of Benzoyl-a-amino-crotonic Acid Azlactone II. J. Biol. Chem. 133, 117 (1940). 

Acetate buffer solution Cautiously mix 40 g sodium hydroxide and 120 mL glacial acetic acid to prepare 1 L aqueous solution. 

Dissolve I g. of finely powdered acetanilide in 5 ml. of cold glacial acetic acid contained in a 25 ml. conical flask. Then in another small flask prepare a solution of 0 42 ml. (1 34 g.) of bromine (care ) in 6 ml. of glacial acetic acid, and add this solution slowly to the acetanilide solution, shaking the latter throughout the addition to ensure thorough mixing. Allow the final mixture to stand at room temperature for 15 minutes. Then... 

For class work it is convenient to make up a single bromine solution by dissolving 7 ml. of bromine in 100 ml. of glacial acetic acid, and using 6-5 ml. of this solution for each preparation. 

Dichloramine-T. Dilute 80 ml, of freshly prepared 2N sodium hypochlorite soluticMi (preparation, p. 525) with 80 ml. of w ter, and then add with stirring 5 g. of finely powdered toluene-p-sulphonamide, a clear solution being rapidly obtained. Cool in ice-water, and then add about 50 ml. of a mixture of equal volumes of glacial acetic acid and water slowly with stirring until precipitation is complete the dichloro-amide separates at first as a fine emulsion, which rapidly forms brittle colourless crystals. Filter off the latter at the pump, wash well with... 

Fit two similar 250 ml. conical flasks, A and B, with reflux water-condensers (using ground-glass joints or rubber stoppers) and connect the condensers in series as before over two water-baths. Prepare a mixture of 2 volumes of acetic anhydride and i volume of glacial acetic acid,... 

The leagent may also be prepared by dissolving 1 ml. of phenylhydrazine in a solution of 1 ml. of glacial acetic acid and 10 ml. of water. This procedure is not so convenient as that from the solid hydrochloride becaiise of the poisonous character of phenylhydrazine (both liquid and vapour). If the liquid is accidentally spilled on the skin, wash it at once with dilute acetic acid, followed by soap and water. 

Preparation of the sulphones. Dissolve the 2 4-dinitrophenyl-sulphide in the minimum volume of warm glacial acetic acid and add 3 per cent, potassium permanganate solution with shaking as fast as decolourisation occurs. Use a 50 per cent, excess of potassium permanganate if the sulphide tends to precipitate, add more acetic acid. Just decolourise the solution with sulphur dioxide (or with sodium bisulphite or alcohol) and add 2-3 volumes of crushed ice. Filter off the sulphone, dry, and recrystaUise from alcohol. 

The best results are obtained with freshly prepared xanthhydrol (reduction of xanthone with sodium amalgam. Section VII,16). Dissolve 0 -25 g. of xanthhydrol and 0 -25g. of the primary sulphonamide in 10 ml. of glacial acetic acid. Shake for 2-3 minutes at the laboratory temperature and allow to stand for 60-90 minutes. Filter oflf the derivative, recrystallise it from dioxan-water (3 1), and dry at room temperature under water pump suction for 30 minutes. 

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