Ammonia method

Barbier, A., Hanif, A., Dalmon, J.-A., and Martin, G.A. 1998. Preparation and characterization of well-dispersed and stable Co/Si02 catalysts using the ammonia method. Appl. Catal. A Gen. 168 333 -3. 

Another approach to the organic nitrogen problem is to use persulfate wet oxidation to convert the nitrogen to nitrate or nitrite, in place of the reduction to ammonia [13,14,24,25]. Results are fully comparable with those from the micro Kjeldahl digestion but the technique is far simpler. The precision should also be higher, since the final step in the measurement, the colorimetric determination of nitrite, is much more precise than any of the ammonia methods. 

The LeBlanc process was the principal method of producing soda ash until 1860 when the Belgian Ernest Solvay (1838-1922) developed the process that bears his name. The Solvay process, sometimes called the ammonia method of soda production, utilized ammonia, NH3, carbon dioxide, and salt to produce sodium bicarbonate (baking soda), NaHCOj. Sodium bicarbonate was then heated to give soda ash. The series of reactions representing the Solvay process are... 

One of the first detailed studies on these systems was that of Beaman (26), who showed that methacrylonitrile polymerizes by an anionic chain mechanism when treated with various bases, including Na in liquid ammonia at —75° C. He noted also that low molecular weight polymers are obtained from reaction of acrylonitrile with butylmagnesium bromide. Foster (56) extended the liquid ammonia method to copolymerization studies in which acrylonitrile was combined with styrene, with methyl methacrylate and with vinyl butyl sulfone. Satisfactory data were obtained only with the sulfone, in which case there was some tendency for alternation. 

Metathesis reactions of MXa with alkaline alkoxides or ammonia (method 5)... 

MC15 with alcohols in the presence of ammonia (method 5) and the alcohol interchange of M(OPr )5 (method 6). Mehrotra proposed later the application of esters in the alcohol interchange reaction for Nb(OEt)5 [223],... 

The interactions with use of various ligands, metals, and ammonium salts (ammonia method) are well developed [202,509,660 663] and represent a considerable contribution in the dissolution of metals in nonaqueous media. The basis of this simple and accessible method of obtaining complexes from bulk metals is the following reaction ... 

Ammonia methods with use of metal oxides are of undoubted interest. The yields of formed complex compounds are 60-90% [202]. For example, the reaction (3.271) of diethyleneamine (L) with a powder of ZnO and ammonium thiocyanate in acetonitrile leads to complex 824a (yield 90%) [676] ... 

Johan Kjeldahl first described his method for the determination of nitrogen in proteinaceous materials in 1883, when he was director of the Chemical Laboratory at the Carlsberg Foundation. At that time there was a pressing need for a more convenient and reliable procedure. Wanklyn s albuminoid ammonia method gave low and erratic results. Kjeldahl developed a succession of modifications that resulted in a technique very different from Wanklyn s - one which is still substantially the same today.65 66... 

Diethyl Tellurium17 (Liquid Ammonia Method) An apparatus suitable for work with liquid ammonia is set up. 12.7 g (0.1 mol) of fine tellurium powder are suspended in liquid ammonia and then 4.6 g (0.2 mol) of sodium are added to the suspension. The mixture is stirred for 4 h. 10.9 g (0.1 mol) of ethyl bromide are added dropwise to the liquid ammonia, and the mixture is stirred for 30 min. The ammonia is evaporated. Water is added to the residue, the aqueous solution is extracted with diethyl ether, and the extract is dried with magnesium sulfate. The ether is evaporated and the residual liquid is distilled yield 7 g (38%) b.p. 138°. 

Methyl l-Methoxyltellurobenzoate)1 A solution of 0.171 g (1 mmol) 2-methoxybenzoyl chloride in 8 ml tetrahydrofuran is added to 0.174 g (1 mmol) of freshly prepared sodium telluride (liquid ammonia method). The mixture is stirred at 0° for 1 h and then filtered. The solvent is evaporated from the filtrate under reduced pressure. The red, oily residue is cooled to — 63° under nitrogen and mixed with 2 ml (32 mmol) iodomethane. The mixture is warmed to — 30° and stirred at this temperature for 2 h. The excess iodomethane is evaporated under reduced pressure below 0°. The residue is treated with 5 ml dichloromethane, the black mixture is filtered, and the filtrate evaporated under reduced pressure below 0° to give yellow crystals yield 84% m.p. 25°. 

A series of very volatile alkaline-earth compounds with pendent ether groups, [M(OC-/-Bu(CH2OR)2)2]2 (M = Ca, Sr, Ba R = i-Pr or Et), have been synthesized by the halide metathesis and metal/ammonia methods as well as by reaction between the metal amides M(N(SiMe3)2)2(THF) and the alcohols HOC-t-Bu(CH2OR)2.48 Alcoholysis of metal amides has... 

The Sheldon group found that the highest conversions were observed with CrS-1 prepared by the ammonia method. CrS-1 made by the fluoride method gave a slightly lower styrene conversion and roughly the same selectivities. The catalyst prepared by the sulfuric acid method gave substantially lower styrene conversions, but the selectivity to benzaldehyde was high. 

Alternatively, higcher product yields are obtained when the bromide dia placement reaction is carried aut by the Gabriel phthalimide method (Sec tion 34.6) rather than by the ammonia method. 

The Ammonia Method. This method depends on the decomposition of cyanogen bromide by ammonia ... 

Dimethyl Ditellurium [Liquid Ammonia Method] An apparatus suitable for work with liquid ammonia is assembled. A 500 ml, three-necked flask is fitted with a reflux condenser, a dropping funnel, and a stirrer. In the flask, 3.2 g (0.14 mol) of clean sodium are added to 100 ml of anhydrous ammonia at — 78°, the mixture is stirred for 1 h, and 18.2 g (0.14 mol) of high purity, powdered tellurium are added in 0.5 g portions. After all the tellurium has been added, 24 g (0.17 mol) of methyl iodide are added dropwise to the stirred, dark-green ammonia solution over 20 min. The cooling bath is then removed, the ammonia is allowed to evaporate, and water is added to the residue. The aqueous mixture is extracted with four 50 ml portions of diethyl ether, the combined deep-red extracts are dried overnight with anhydrous calcium chloride, the diethyl ether is evaporated under vacuum, and the residue is distilled yield 7.6 g (38%) b.p. 97°/9 torr. The freshly prepared dimethyl ditellurium is a heavy, dark-red liquid that solidified on standing for a few days at 20°. The liquid is regenerated when the solid is distilled under vacuum. Similarly prepared were ... 

PC spectrophotometer equipped with a reflectance attachment. FTIR of pyridine adsorbed and temperature-programmed desorption (TPD) of ammonia methods has been previousiy reported [10]. 

The submitter states that a number of aromatic mono-and dinitriles have been prepared by this procedure vvith slight or no modification in the temperature. The reaction mixtures were usually worked up by the acetone-ammonia method described in Note 6. Among the compounds prepared by this method are o-nitrobenzonitrile, o-bromobenzonitrile, w-methoxy-benzonitrile, 4,4 -dicyanodiphenylsulfone, 4,4 -dicyanostilbene, a,7-di-(4-cyanophenoxy)propane. With the last, a temperature of 185 190° for 20 minutes gave the best results. The yields before purification ranged between 75% and 95% and after purification between 63% and 79%. Aliphatic acids give low yields of the corresponding nitriles and, in some cases, chlorinated by-products. 

The only known way to synthesize 3-substituted 6-phenyl-l,4,2-oxathiazines 8 is by ring expansion of 1,3-oxathiolinm salts 7 (see Houben-Weyl, Vol. E8a, p lOff) with azide ions (Method A), iodine/ammonia (Method B) or sulfenamides 11,12 (Method C).47 48 As intermediates, sextet structures of the nitrenium ion or nitrene type are under discussion. It is remarkable that the ring expansion obviously only incorporates the nitrogen function into the C—O bond and therefore only produces 8. 1,4,3-Oxathiazine derivatives, which could equally be formed, were not discovered.48 All three methods A C produce 1,4,2-oxathiazines 8 in yields which are moderate at best. The reaction of 2-dialkylamino-5-phenyl-l,3-oxathiolium perchlorates 7b, 7c with N, V-dimethylthiocarbamoylsulfenamide 11 yields, sometimes even as the main product, also bis(4-pheny -2-dialkylamino-5-thiazolyl) sulfides 9.48... 

NIOSH. 1984. Ammonia Method 6701. NIOSH manual of analytical methods 1. Cincinnati, OH National Institute for Occupational Safety and Health., 6701-1 to 6701-4. 

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