White Snow

P-Cyanopyridine. Mix 25 g. of powdered nicotinamide with 30g. of phosphoric oxide in a 150 ml. distilling flask by shaking. Immerse the flask in an oil bath and arrange for distillation under a pressure of about 30 mm. Raise the temperature of the oil bath rapidly to 300°, then remove the oil bath and continue the heating with a free flame as long as a distillate is obtained. The nitrile crystallises on cooling to a snow-white solid. Redistil the solid at atmospheric pressure practically all of it passes over at 201° and crystallises completely on cooling. The yield of p-cyanopyridine, m.p. 49°, is 20 g. 

The filtrate and the washings contain in solution a small quantity of the product. This is recovered by distillation with steam. The acid distillate will consist of snow-white crystals (if it is protected from light) and a solution of the compound. The solid is removed by filtration and washed. The filtrate is made neutral with sodium carbonate and extracted with ether. Upon drying and evaporating the ethereal layer will yield mononitrothiophene contaminated with dinitrothiophene (Note 5),... 

If the nitration is caiiied out in accordance with this outline, the product will be crystalline and pale yellow in color. The color is due to traces of dinitrothiophene and the other impurities. Mononitrothiophene has been crystallized by earlier workers from ether, alcohol, benzene, and other solvents. As a rule these solvents fail to yield a snow-white product. It has been found in this work that petroleum ether (b.p. 20-40 ) possesses decided advantages in that by prolonged refluxing it extracts mononitrothiophene but does not readily dissolve the impurities. With petroleum ether, snow-white crystals have been obtained in needles 10 to 20 cm. in length. 

It occurs in brilliant snow-white crystals, m.p. 305° (dec.) and is readily soluble in water or aqueous alcohol. The benzoyl derivative, m.p, 209°. is crystalline and on methylation gives a-coeaine, a base crystallising in prisms, m.p. 87°, and yielding an aurichloride, m.p. 222° (dec.), crystallising in leaflets. It is bitter to the taste but has no local anjesthetic action. 

Baker and Smith have isolated an alcohol of the formula C,oH,gO from the cajuput oil, distilled from the leaves of Melaleuca uncinata. The alcohol, which is probably an open-chain compound, forms snow-white crystals, melting at 72 5°, and having a specific rotation + Sfi fifi . 

When the aldehyde is heated on the water-bath with 25 per cent, hydrochloric acid, it yields a triphenylmethane derivative, nonamethoxy-triphenylmethane, a body consisting of snow-white crystals, melting at 184 5°. The action of concentrated nitric acid upon the solution in glacial acetic acid of this triphenylmethane derivative gives rise to 1, 2, 5-trimethoxy-4-nitrobenzene (melting at 130°). With bromine, nonamethoxytriphenylmethane combines, with separation of a molecule of trimethoxy bromobenzene, into a tribromo additive compound of hexamethoxy diphenylmethane, a deep violet-blue body. The 1, 2, 5-tri-methoxy-4-bromobenzene (melting at 54 5°) may be obtained more readily from asaronic acid. 

Schnee-flocke, /, snowflake. gips, m. snowy (foliated) gypsum, -glockcben, n. snowdrop, -grenze, /, snow line, -webe, /. snowdrift. schneeweisB, a. snow-white. 

Schneewelss, n. snow white (zinc white), schneidbar, a. capable of being cut, sectile, scis-sile. 

The crude product is dissolved in five times its weight of water, and after clearing with a little Norite the solution is diluted with one and one-half volumes of 95 per cent alcohol. The product separates in well-formed, snow-white crystals, and after standing for several days in an ice chest is collected with suction on a Buchner funnel. The yield of purified histidine monohydrochloride is 75-80 g. (Note 5). The compound melts at 251-2520, with decomposition. The amino acid is not race-mized by the procedure employed, and shows the characteristic optical activity, [a]n6° = +8.00, in the presence of three moles of... 

Bilotta, J.J. and Waye, J.D. (1989). Hydrogen peroxide enteritis the snow white sign. Gastrointest. Endosc. 35, 428-430. 

The pentamethyl benzene obtained in this way is nearly pure, and one recrystallization from 95 per cent alcohol or from a mixture of equal volumes of alcohol and benzene gives a snow-white product, but the product generally melts over too wide a range for practical purposes. However, if fraction VII is refractionated under diminished pressure and the fraction boiling at i23-i33°/22 mm. (practically all at 127-1290) is collected and recrystallized as in the following paragraph, a product melting quite sharply at 52° (true m.p. 530) is obtained. 

The dried product is then recrystallized from 30-35 ml. of a 1 3 mixture of boiling benzene and carbon tetrachloride (Note 7). The yield of snow-white crystals is 15-15.7 g. (82-86%) the recrystallized product melts at 131-132° and is sufficiently pure for synthetic purposes. A second recrystallization gives a product which melts at 132-133° (Notes 8 and 9). 

At the end of the heating period the contents of the flask will have solidified. To the cold mixture 40 ml. of water is added to hydrolyze the potassium methoxide and precipitate the pyrimidine the fine crystals are filtered and dried. The crude product is placed in a 500-ml. distilling flask with 250 ml. of purified kerosene (Note 3). On distilling the kerosene, the pyrimidine codistils and solidifies in the receiving flask to a snow-white mass of crystals. These are filtered, washed well with petroleum ether, and dried in an oven at 100°. The yield of pure material, melting at 182-183°, is 27.5-28.7 g. (67-70%) (Note 4). 

The 2-chlorolepidine is extracted, using two 750-ml. portions of ether (Note 1). The extract is shaken with two 200-ml. portions of water and then dried over 50 g. of potassium carbonate. After removal of the ether, the residual oil is distilled from a 200-ml. modified Claisen flask.2 The colorless distillate boils at 132-135°/3 mm. and weighs 118-122 g. (89-92%). The distillate is melted if necessary and poured into 250 ml. of petroleum ether (b.p. 40-50°) the solution is then chilled in a freezing mixture the crystals are filtered by suction and dried in a vacuum desiccator over paraffin. The snow-white 2-chlorolepidine melts at 58-59° and weighs 114-118 g. (86-89%). 

A. t-Butyl hydrazodiformate. A solution of 28.6 g. (0.2 mole) of /-butyl azidoformate and 26.4 g. (0.2 mole) of /-butyl carba-zate in 60 ml. of pyridine (Note 1) is allowed to stand at room temperature for 1 week and is then diluted with 500 ml. of water. The snow-white microciystalline powder that separates is removed by filtration and is washed with two 50-ml. portions of water. The yield of air-dried hydrazide, m.p. 124-126°, is 35.5-37 g. (77-80%). i,The product is pure enough for most applications but may be purified by recrystallization from a 1 1 mixture of benzene and ligroin (60-90°) from which it separates as small white needles, m.p. 124—125.5°. The recovery is 92%. 

An albino does not have the ability to generate melanin, so their hair is snow white, and their skin looks pale pink in colour because the blood corpuscles beneath its surface are the only chromophore they have. 

The crystalline mass of needles is broken up and the cold solution filtered (suction). The filter cake is sucked dry and then washed with anhydrous ether. If necessary the product may be recrystallized from methanol using 5 ml for each gram. The snow white product melts at 198-200° C. 

Carefiil control of the reaction temperature at higher temperatures (627° 3°C) was necessary to reproducibly obtain a completely fluorinated pure white material. A snow-white material was obtained by direct fluorination of graphite at this temperature. Elemental analysis showed the calculated empirical formula to be CF112 003.20... 

Mirex and chlordecone are two separate synthetic insecticides that have similar chemical structures. They do not occur naturally in the environment. Mirex is a snow-white crystalline solid and chlordecone is a tan-white crystalline solid. Both compounds are odorless and neither burns easily. 

Hauff, K., Fischer, R.G., and Ballschmiter, K. Determination of C1-C5 alkyl niPates in rain. snow, white frost, lake, and tap water by a combined codistillation headspace chromatography technique. Determination of Henry s law constants by head-space GC, Chemosphere, 37(13) 2599-2615, 1998. 

Compound 30 separates as a snow white glistening powder. It dissolves well in THF and toluene, poorly in DME and benzene. By metal-lation of the PH group in compound 28 with LiBu it is not possible to obtain an additional ring closure by elimination of LiCl to yield the corresponding bicyclic molecule. Undetermined molecular associations occur instead. 

The distilled dlamide Is a pale yellow oil at room temperature It freezes in the refrigerator (+4 C) If seeded within some hours. The first spontaneous crystallization took several weeks. It can also be obtained as snow white crystals from diisopropyl ether/hexane, rap 15-16°C. 

Finally, Pemety even explains the presence of those carefully polished, snow-white cubes made from marble (marbre) in Duchamp s symbolic bird-prison arranged around carefully measured temperature ranges MARBLE. Properly speaking, the Marble of the Hermetic Sages means their Mercury. They... 

This treatment must obviously be omitted on the first preparation the product will be light pink rather than snow white, as obtained when the reagents are purified in this manner. 

Meinrad Meister 2894 Snow White Drive Mansfield, FL 69821... 

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