Nitrocyanamide salts

The explosive properties of the potassium salt of nitrocyanamide first attracted McKay s [37] attention. He separated this potassium salt as a by-product from the preparation of aliphatic diazo compounds by the hydrolysis of N-alkyl-N-nitroso-N -nitroguanidines with an aqueous solution of sodium hydroxide at temperatures from 0°C to room temperature  

The same author et al. (McKay, Hatton, G. W. Taylor [38]) prepared a number of nitrocyanamide salts by the action of the chlorides of various metals on the silver salt in suitable solvents or the by reaction of the carbonates of various metals with a solution of nitrocyanamide in acetonitrile, and found that some of these salts have initiating properties. The majority, however, cannot be recommended for practical use, their sensitiveness to impact being too low (they are not exploded by a 5 kg weight falling from a height of 300 cm). 

Harris [39] reports that only the following nitrocyanamide salts possess greater sensitiveness and may be considered to be of practical use potassium, tin, lead, barium and silver nitrocyanamides. 

Comparing with the experiments of Grant and Tiffany [40] Harris states that silver and barium nitrocyanamides show an initiation capacity the same as that of an 80 20 mixture of mercury fulminate and potassium chlorate, but weaker than that of a mixture of lead azide and lead styphnate. This can be seen from Table 38 quoted by Harris  

Primary explosive Minimum initiating charge necessary for explosion of 1.25 g of tetryl Sand crushed per g 

---

In spite of their fairly promising initiating properties, nitrocyanamide salts are of no practical use due to their high hygroscopicity. 

Other reactions of aminoguanidine with nitrous acid Cyanamide salts Silver cyanamide Nitrocyanamide salts Nitrophenol salts Lead picrate Lead styphenate Lead stypheratc manufacture... 

Harris [25] isolated this substance by the action of anhydrous hydrogen chloride on the solution of the silver salt of nitrocyanamide in acetonitrile. It has explosive properties but it is of no practical value due to the difficulty of preparing it. On the other hand its salts may be of practical value. These salts and their preparation will be discussed in the chapters dealing with initiating explosives (p. 211). 

This compd was rapidly cleaved by dil KOH to yield K nitrocyanamide n-butylnitramine, isolated as the monohydrate of the Ba salt. 

Finally, alkyl halides are readily converted into isocyanates, in very good yields, by reaction with the silver salt of nitrocyanamide (equation 52)404. This is the first reported reaction for the preparation of isocyanates, from alkyl halides, that is of a general nature. The direct reaction of halides with metal cyanates gives very erratic results. 

---