Of sodium metal

Sodium ethoxide is prepared by the reaction of sodium metal with ethanol... 

The use of alkaU metals for anionic polymerization of diene monomers is primarily of historical interest. A patent disclosure issued in 1911 (16) detailed the use of metallic sodium to polymerize isoprene and other dienes. Independentiy and simultaneously, the use of sodium metal to polymerize butadiene, isoprene, and 2,3-dimethyl-l,3-butadiene was described (17). Interest in alkaU metal-initiated polymerization of 1,3-dienes culminated in the discovery (18) at Firestone Tire and Rubber Co. that polymerization of neat isoprene with lithium dispersion produced high i7j -l,4-polyisoprene, similar in stmcture and properties to Hevea natural mbber (see ELASTOLffiRS,SYNTHETic-POLYisoPRENE Rubber, natural). 

Cyanopyiidine (15) reacts with ketones not beating an a-hydiogen in the presence of sodium metal to afford a tertiary alcohol (a precursor of azacydonol) in high yield, eg, the reaction of (15) and benzophenone yields the tertiary benzyl alcohol [1620-30-0] (23) ... 

Sodium methoxide was prepared just prior to use from 23.0 g (1.0 g-atom) of sodium metal and 400 mL of anhydrous methanol (distilled from magnesium turnings), then cooled to room temperature. 

The chemical resistance of PTFE is exceptional. There are no solvents and it is attacked at room temperature only by molten alkali metals and in some cases by fluorine. Treatment with a solution of sodium metal in liquid ammonia will sufficiently alter the surface of a PTFE sample to enable it to be cemented to other materials using epoxide resin adhesives. 

A piece of sodium metal stored under kerosene m a metal container is removed from ajar and blotted with dry napkin or filter paper With a sharp knife, the layer of oxides IS removed until a shiny surface appears The removed layer is then destroyed carefully by adding very small pieces (not larger than 0 5 cm) to precooled 200 mL of methanol or ethanol... 

Caution Addition of 0 5 cm pieces of sodium metal to methanol or ethanol must be done in a chemical hood and behind a safety shield. Addition should be slow to minimize evaporation loss of methanol or ethanol. No flames or burner should be permitted in the area. Disposal of sodium metal must be earned out in someone s presence. 

A modification of the K-R reaction was introduced by Mozingo. This method involved reacting an o-hydroxyacetophenone with an ester in the presence of metallic sodium to form a 1,3-diketone. Treatment of the diketone with an acid then delivered the chromone via an intramolecular cyclization reaction. This method was applied to the preparation of 2-ethylchromone (21). 0-hydroxyarylketone 22 was allowed to react with ethyl propionate (23) in the presence of sodium metal.The resulting sodium enolate was then quenched with acetic acid to deliver the 1,3-diketone 24. Upon heating 24 in glacial acetic acid and hydrochloric acid, 2-ethylchromone (21) was delivered in 70-75% overall yield. 

A process for the preparation of functionalized pyridines from diacetylene and the ethyl ester of /3-aminocrotonic acid and acetylacetonimine (72ZOR1328 75DIS) has been described. Owing to the lower nucleophilicity of nitrogen in the initial enamine esters and enamine ketone, the reaction with diacetylene occurs in the presence of sodium metal (80°C, dioxane, 3 h, yield of up to 20%). 

The quaternary salt is now treated with ethoxide ion in the presence of cinnamalde-hyde so that the ylide reacts in situ as it is produced. A solution of sodium ethoxide is prepared by slowly adding 0.75 g of sodium metal to 100 ml of absolute ethanol in a dry Erlenmeyer flask (hood). In a second flask, the phosphonium chloride is dissolved in 150 ml of absolute ethanol, cinnamaldehyde (2.9 g) is added and the flask is swirled while the ethoxide solution is added a transient orange-red color indicates the formation of the ylide. 

There were placed 120 g of Lthree-necked flask equipped with a stirrer thermometer and methanol/dry ice cooling and 1.5 liters of liquid ammonia were allowed to enter at -40°C. Then there were added under continuous cooling 50 g (2.17 mols) of sodium metal in portions of 1 to 2 g during the course of one hour. The end of the reaction was recognized by the continuation of the blue color. After the end of the reaction the excess sodium was destroyed by the addition of ammonium chloride and the ammonia vaporized at normal pressure. The residue was taken up in 500 ml of water and concentrated in a vacuum to 200 ml in order to remove residual ammonia, and again treated with 300 ml of water. The entire operations were carried out under a nitrogen atmosphere. 

Prepares solution of sodium methylate by dissolving 3.9 g of sodium metal in 500 ml of methanol. Add 39.0 g of 7-chloro-1,3-dihydro-5-phenyl-2H-1,4-benzodiazeplne-2-one. Evaporate the reaction mixture to a residue and dissolve the residue in 170 ml of dimethylformamide. Add 30 g of 2,2,2-trifluoroethyl Iodide and stir at room temperature for Vi hour, then heat to 60°C to 70°C for an additional 7 hours. Add 19 g of 2,2,2-trifluoroethyl iodide and resume the heating and stirring at 60°C to 70°C for an additional 16 hours. Filter off the solids and evaporate the filtrate to a residue in vacuo. Triturate the residue with water and extract with ethyl ether. Wash the ethereal extract with water, dry over anhydrous sodium sulfate and evaporate the solvent to a residue. 

In 450 cc of methanol is added 47 grams of sodium metal and the mixture allowed to completely react to form a methanol solution of sodium methoxide. The methanol solution of sodium methoxide is then cooled to 60°C and 68 grams of thiourea which has been thoroughly dried is added with stirring until a uniform solution is formed. Thereafter, 157 grams of diethyl allyl-(1-methylbutyl)malonate is added to the solution of the sodio derivative of thiourea at a temperature of 55°C and the condensation reaction mixture maintained at the said temperature for 24 hours. Methyl alcohol is removed under vacuum during the course of the reaction while maintaining a temperature of 55°C. 

This 0 -benrylmercaptopropionylglycine (60 g) is dissolved in 400 ml of liquid ammonia, kept at about -50 C, and 12g of sodium metal is gradually added thereto. After the reaction, excess ammonia is removed therefrom, the residue is dissolved in water, washed with ether and the residual aqueous layer is adjusted to pH 1 with hydrochloric acid and concentrated in vacuo in a stream of hydrogen sulfide. The crystalline residue is dried and recrystallired from ethyl acetate to give 25 g of 0 -mercaptopropionylglycine of melting point 95°C to 97°C. 

If a piece of sodium metal is lowered into a bottle of chlorine gas, a reaction takes place. Table salt, NaCl, is formed. 

Calcium metal is the usual reducing agent used in stripping plutonium and americium from these residue salts. Other active metals, such as sodium metal, show good potential for use as a reducing agent. In the case of sodium metal, the reduction byproduct would be NaCl per the following reaction. 

For example, sodium is a soft, shiny metal that reacts vigorously with water. When we drop a small lump of sodium metal into a container of water, hydrogen gas forms rapidly and sodium hydroxide is produced in solution (Fig. H.l). We could describe this reaction in words ... 

K.18 The industrial production of sodium metal and chlorine gas makes use of the Downs process, in which molten sodium chloride is electrolyzed (Chapter 12). Write a balanced equation for the production of the two elements from molten sodium chloride. Which element is produced by oxidation and which by reduction ... 

Self-Test 6.10A The enthalpy of fusion of sodium metal is 2.6 kj-mol 1 at 25°C, and the enthalpy of sublimation of solid sodium at that temperature is 101 kj-mol 1. What is the enthalpy of vaporization of sodium at 25°C ... 

We have already described the refining of copper and the electrolytic extraction of aluminum, magnesium, and fluorine. Another important industrial application of electrolysis is the production of sodium metal by the Downs process, the electrolysis of molten rock salt (Fig. 12.15) ... 

Phenyl-2(lH)Pyridone Sodiim Salt. A solution of sodium metal (0.25 g, 11.3 mmol) and anhydrous methanol (10 mL) was allowed to react to form sodium methoxide. Pyridone IV (1.88 g, 11 mmol) was added to the solution and allowed to stand at room temperature for 24 h. The methanol was removed under reduced pressure and the residue was extracted with hot benzene 3 times and dried in the Abderhalden drying pistol for 30 min. The yield was 1.7 g (82%). 

The reaction of sodium metal with O2 gas produces a crust of sodium peroxide, which blocks additional... 

The reaction of sodium metal with molecular chlorine gas to produce solid sodium chloride can be analyzed by breaking the overall process into a series of steps involving ions in the gas phase. 

Both polymers 10 and 11 are soluble in common organic solvents, melt without decomposition, and can be drawn into the fibers. Molecular weights of the polymers 10 and 11, determined by gel permeation chromatography with tetrahydrofuran as the eluant after purification by reprecipitation from benzene-ethanol, showed a broad monomodal molecular weight distribution. The degree of polymerization depends on particle size of sodium metal. Polymers with molecular weights of 23,000-34,000 are always obtained, if fine sodium particles are used. 

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