Sodium cyanamide

By the hydrolysis of dialkyl cyanamides with dilute sulphuric acid this method gives pure secondary amines. The appropriate dialkyl cyanamide is prepared by treating sodium cyanamide (itself obtained in solution from... 

No reaction takes place below 500°C when sodium cyanide and sodium hydroxide are heated in the absence of water and oxygen. Above 500°C, sodium carbonate, sodium cyanamide [19981-17-0] sodium oxide, and hydrogen are produced. In the presence of small amounts of water at 500°C decomposition occurs with the formation of ammonia and sodium formate, and the latter is converted into sodium carbonate and hydrogen by the caustic soda. In the presence of excess oxygen, sodium carbonate, nitrogen, and water are produced (53). 

Until the 1960s, when HCN became widely available, NaCN was made by the Castner process via sodamide and sodium cyanamide ... 

Cyanamid-calcium, n. calcium cyanamide. -natrium, n. sodium cyanamide. 

Another cyanamide compound that has a number of significant uses is sodium cyanamide, which is prepared as shown below. Sodium amide is obtained by the reaction of ammonia with Na at 400 °C. 

The reaction between sodium amide and carbon produces sodium cyanamide,... 

The major use of sodium cyanamide is in the production of sodium cyanide, a compound that is used extensively in preparing solutions for the electroplating of metals. Another use for NaCN is in extraction processes employed to separate gold and silver from ores as a result of their forming complexes with CN . Sodium cyanide, an extremely toxic compound, is also used in the process known as case-hardening of steel. In this process, the object to be hardened is heated and allowed to react with the cyanide to form a layer of metal carbide on the surface. 

Castner (2) A process for making sodium cyanide. Sodamide is first made by passing ammonia gas over molten sodium. The molten sodamide is then poured over red-hot charcoal, which converts it first to sodium cyanamide and then to sodium cyanide ... 

Sodium compounds, 22 760-761, 762 as soap bar additives, 22 744 Sodium cyanamide, 8 184 Sodium cyanate, 8 184 Sodium cyanide, 8 183-184 analysis, 8 190 economic aspects, 8 189 health and safety factors, 8 190-191 manufacture, 8 187-189 properties, 8 184-187, 185t silver extraction via, 22 638, 646-647 uses, 8 191... 

Benzhydroxamic chloride reacts with sodium cyanamide (153) in dry acetone to give (154), a compound which has alternatively been prepared by Curtius rearrangement of the azide (155)... 

Sodium amide reacts with carbon at 800° C to form sodium cyanamide and... 

Via a same intermediate, the action of sodium cyanamide on phenylchloroxime or the action of hydroxylamine on ethyl-N-cyano-benzimidate, yields 3-phenyl-5-amino oxadiazole (61a, 33c). 

M. Traube noted that hydrogen peroxide is formed during the slow oxidation of copper in the presence of ammonium carbonate. H. J. H. Fenton observed that when ammonium carbonate is treated with metallic sodium, cyanamide, Cy.NH2, is formed by the loss of three mols. of water 2(NH4)2C03+3Na2=6Na0H -t-3H2+2CyNH2. H. Delbriick investigated the action of potassium on the salt. 

To the solution of sodium cyanamide thus prepared, 380 g. (3.14 moles) of allyl bromide (Note 3) and 660 cc. of 95 per cent alcohol are added. The mixture is then heated on a water bath with good stirring until it refluxes gently, and the heating and stirring are continued for two and one-half hours. Then the reflux condenser is replaced by one set downward for distillation. The stirring is continued and the alcohol is distilled until about 500 cc. has been collected. The distillate may be discarded or used for the recovery of alcohol (Note 4). 

Stirring for one hour in the cold permits the relatively insoluble calcium cyanamide to react with sodium hydroxide and go into solution as sodium cyanamide. If the temperature is not kept below 250 during this time, there is some tendency for polymerization to dicyanodiamide. 

The preparation of pure symmetrical secondary amines (e.g. dibutylamine, Expt 5.199) is conveniently achieved by the hydrolysis of dialkylcyanamides with dilute sulphuric acid. The appropriate dialkyl cyanamide is prepared by treating sodium cyanamide (itself obtained from calcium cyanamide and aqueous sodium hydroxide solution) with an alkyl halide. In this case the reagent [ —C=N]20 may be regarded as a masked NH group. 

Sodium cyanamide (50 gms.). is gradually added to concentrated hydrochloric acid (1 19), 74 gms. while well cooled, and the water is then removed by distillation in vacuo. The residue, which solidifies on cooling, is extracted with ether, and the ether evaporated the cyanamide solidifies when cooled. Yield, about 10 gms, M.p. 40°. 

The Beirut reaction has also been employed to prepare 1-hydroxybenz-imidazole 3-oxides or benzimidazole 1,3-dioxides, when nitroalkanes have been used as enolate-producer reagent [46,47], and benzo[e][l,2,4]triazine 1,4-dioxides when Bfx reacts with sodium cyanamide [48-50]. 

Sodium chloro propionate see Chloro propionic acid Sodium cyanamide dodine... 

Sodium cyanamide is used mainly in the production of sodium cyanide that is used extensively in preparing solutions from which metals are electroplated. Sodium cyanide is also used in an extraction process for obtaining gold and silver, because these metals form stable complexes with CN. The sodium cyanamide is obtained by the reaction of sodium amide, NaNH2, with carbon ... 

The sodium cyanamide reacts with carbon to produce the cyanide ... 

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