Guanidines nitroguanidines

Nitroguanidine Guanidine, Sulfuric acid. Nitric acid... 

Nitroguanidine Guanidine, Sulfuric acid, Water Secondary high explosive, Found in triple-base smokeless powders... 

CMC-Silver azide Black Powder Picric acid(coarse) Picric acid(fine) Trinitrotoluene (TNT) Nitroguanidine Guanidine nitrate m-Dinitrobenzene Others Dibenzoylperoxide Sporting paper cap Flat paper cap DPT" ... 

Ma.nufa.cture. Nitroguanidine may be made by several methods. In all the processes guanidine nitrate is the iatermediate which is then dehydrated with sulfuric acid. When used ia propellants, the average particle size of nitroguanidine has to be carefully controlled. 

In the commonly used Welland process, calcium cyanamide, made from calcium carbonate, is converted to cyanamide by reaction with carbon dioxide and water. Dicyandiamide is fused with ammonium nitrate to form guanidine nitrate. Dehydration with 96% sulfuric acid gives nitroguanidine which is precipitated by dilution. In the aqueous fusion process, calcium cyanamide is fused with ammonium nitrate ia the presence of some water. The calcium nitrate produced is removed by precipitation with ammonium carbonate or carbon dioxide. The filtrate contains the guanidine nitrate that is recovered by vacuum evaporation and converted to nitroguanidine. Both operations can be mn on a continuous basis (see Cyanamides). In the Marquerol and Loriette process, nitroguanidine is obtained directly ia about 90% yield from dicyandiamide by reaction with sulfuric acid to form guanidine sulfate followed by direct nitration with nitric acid (169—172). 

S. Levmore, PTir Blast Parameters and Other Characteristics of Nitroguanidine and Guanidine Nitrate, TR 4865, PTA, Dover, N.J., 1975. 

The definition of crop residues for thiamethoxam and thiacloprid includes the parent and its metabolite fV-(2-chlorothiazol-5-ylmethyl)-fV -methyl-A"-nitroguanidine (designated the guanidine compound) for thiamethoxam, and 3-(6-chloro-3-pyridylmethyl)-l,3-thiazolidin-2-ylideneaminocarboxamide (designated the amide compound) for thiacloprid (Figure 3). 

Ordnance propellants are required to give the minimum of muzzle flash, smoke and barrel erosion. All these objectives are assisted by adding to the propellant a proportion of nitroguanidine (picrite), made by treating guanidine nitrate with sulphuric acid and brought to very fine particle size by recrystallisation and disintegration. 

Welland A process for making nitroguanidine, an explosive. Cyanamide dimer is reacted with ammonium nitrate to form guanidine nitrate, which forms nitroquanidine when dehydrated by heating with 96 percent sulfuric acid. See also Marquerol and Loriette. 

The main starting compound is the labeled nitroguanidine 257 obtained from guanidine with isotope-labeled potassium nitrate. Reduction of 257 to hydrazine carboximidamide 258 was carried out with zinc and, then, ring closure to 3-amino[l,2,4]triazole 259 was carried out using formic acid. Finally, the ring closure to form the [l,2,4]triazine ring - similar to other procedures presented in Scheme 54 - was perfected by reaction with nitrous acid followed by treatment with ethyl nitroacetate to 260. 

The previous review1 has treated in detail only the following amines methylamine, dimethylamine, trimethylamine, 2-aminoethanol, ethylenediamine, nitroguanidine and similar ones. In the period of the present review, some simple molecules of interest have been treated such as the aminoethanol series, including mono-, di- and tri-substituted derivatives, as well as a number of derivatives of guanidine. These will be dealt with for purposes of internal comparison. 

Acetyl-4-(4/-sulfophenyl)-3-tetrazene, 2982 Aluminium azide, 0082 Aluminium tetraazidoborate, 0059 Amino guanidine, 0507 1-Amino-3-nitroguanidine, 0495 5-Aminotetrazole, 0461 5-Amino-l,2,3,4-thiatriazole, 0413... 

Medard (Ref 8) examined properties of HN mixtures with NH4NO3. Guanidine Nitrate,. Nitroguanidine, and Ethylenediamine Nitrate. 

N-(j3-Nitroxyethyl)-N -nitroguanidine or 1-(2-Nitroxyethyl)-3-nitro-guanidine. 02N0.CH2.CH2NH.C( NH)NH.N02 mw 193.13, N 36.26% crysts (from 95% ale), mp 161° (dec), explodes by impact. The compd was prepd by suspending jS-Hydroxyethylnitroguanidine in acetic anhydride and adding dropwise 99% nitric acid at -5° for 10 mins. The compd explodes by impact (Ref 2)... 

Jousselin [26] prepared nitroguanidine by the action of anhydrous nitric acid or sulphuric acid on guanidine nitrate. The preparation of this substance by the action of sulphuric acid has been developed as an industrial method for the production of nitroguanidine. The method described by Marqueyrol and Loriette [27] follows somewhat different principles. It consists in acting with anhydrous nitric acid on guanidine sulphate which, in turn, is obtained on treating dicyandiamide with sulphuric acid. 

Nitroguanidine exists in two crystalline forms. The a-form results from the action of sulphuric acid on guanidine nitrate followed by the precipitation of the product with water. This form crystallizes from water in long, fairly flexible needles. 

The y -form is produced either alone or together with some of the a-compound, by the nitration of the mixture of guanidine sulphate and ammonium sulphate which results from the action of sulphuric acid on dicyandiamide. The /Worm crystallizes from water in thin, elongated plates. It is converted into the a-compound by solution in sulphuric acid and precipitation with water. Both forms of nitroguanidine melt at the same temperature. Several authors quote different melting points 232, 246, 257°C. 

According to equation (19) decomposition also occurs on boiling nitroguanidine in an aqueous solution of ammonium carbonate, with liberation of nitrous oxide and ammonia. The latter combines with the cyanamide also resulting from reaction (19) and guanidine carbonate is formed in almost quantitative yield. 

The same N-alkyl-N -nitroguanidines are obtainable by the nitration of alkyl-guanidines (Davis and Elderfield [51]). 

Bourjol [59] reviewed various methods of preparing nitroguanidine from guanidine nitrate and sulphuric acid, and also carried out extensive experiments to find the most convenient laboratory method of carrying out the reaction. 

In the method outlined above 136 kg of guanidine nitrate and 300 kg of 98% sulphuric acid are used to produce 100 kg of nitroguanidine. 

Another method of nitroguanidine preparation is that of Marqueyrol and Loriette mentioned already [27]. According to Aubertein [61], here nitroguanidine is formed by the following reactions dicyandiamide is heated with 60% sulphuric acid at 150°C to form guanidine sulphate which however is not isolated. Instead, the reaction mixture is treated directly with a 30% excess of anhydrous nitric add at 25°C. Nitroguanidine, m.p. 257°C, is prepared in this manner in a 91 % yield. 

Manueli and Bernardini [17] proposed an easily fusible mixture consisting of ammonium nitrate, guanidine nitrate and nitroguanidine. According to them such mixtures may be melted at a temperature below 130°C. The explosive Albit, based on Manueli and Bernardini s patent, consisting of six parts of ammonium nitrate, two parts of guanidine nitrate and two parts of nitroguanidine, has been used in Italy. 

Di(aminoguanidinium)-l,6-dinitrobi guanidine. See Bis(aminoguanidinium)-l,6Tdi-nitroguanidine in Vol 1, p A214-R... 

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