The preparation of nitroguanidine

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. 

Krotinger and McCaleb [60] worked out a general method for preparing explosives in the form of fine crystals. It consists of introducing a hot solution into a cold diluting liquid. 

In the case of nitroguanidine, a hot aqueous solution was introduced into cold methanol. Still finer and more uniform crystals were prepared by introducing a cold solution in n-butanol into carbon tetrachloride. The results are given in Table 7. 

Solvent Diluting liquid Average crystal size Limits of the crystal size M Ratio (length) (width) 

acidic nitroguanidine is dissolved in a boiling mixture of water and the mother liquor from previous crystallization. To 1 part of nitroguanidine 14-16 parts of solvent are added. The solution is neutralized with ammonia, filtered and chilled by injecting the hot (approximately 100°C) solution into a vessel under reduced pressure this results in lowering the temperature of the solution to 45°C. A crystalline 

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This method is commonly applied to the nitration of primary amines (3) and in particular the preparation of nitroguanidine, nitrourea etc., as well as in the nitration of secondary amines (4) ... 

This filtrate on evaporation to dryness and baking at 100 0 leaves a residue of 650 g., which is suitable for the preparation of nitroguanidine (p. 68). 

Guanidine nitrate is of interest to us both as an explosive itself and a component of explosive mixtures, and as an intermediate in the preparation of nitroguanidine. All other salts of guanidine require strong mixed acid to convert them to nitroguanidine, but the nitrate is converted by dissolving it in concentrated sulfuric acid and pouring the solution into water. 

The procedure, under conditions somewhat different from those described in the patent, is illustrated by our process for the preparation of -nitroguanidine see page 383. 

Although by our convention the following preparative method is not a nitration, we include it here for the sake of completeness, since it is used in the preparation of Nitroguanidine and Nitrourea... 

V. Milan and co-workers. The Preparation of High Bulk Density Nitroguanidine, Rpt. 3037, NAVORD, Washington, D.C., 1957. 

JPR269>. 1,3,5-TriaIIyl-hexahydro-l,3,5-triazine has been used in the preparation of a C-4 unsubstituted azetidinone which is the starting material for the synthesis of penems and cephams <00S289>. A novel method for the preparation of AfW-disubstituted-Af"-nitroguanidines via 2-nitroimino-hexahydro-1,3,5-triazine derivatives has been studied <00TL7187>. 

Hydrazine salts have been prepared by the action of hypochlorites on ammonia1 or urea 2 by the hydrolysis of salts of sulfohydrazimethylene disulfonic acid 3 by the hydrolysis of triazoacetic acid 4 by the reduction of diazoacetic ester 5 by the reduction of nitroguanidine followed by hydrolysis 6 by the reduction of the nitroso derivatives of hexamethylene tetramine 7 by the reduction of nitrates or nitrites with zinc in neutral solution 8 by the action of sodium bisulfite on hyponitrous acid... 

The following substances were prepared studied by McKay Wright (Ref 1) starting with the reaction of nitroguanidine with ethylene-diamine to give 2-nitramino- A 2-imidazoline ( A2 is used to indicate that a double bond is attached at position 2) ... 

It was observed that the nitroso-nitroguanidines may cause skin irritation. The higher alkylnitrosonitroguanidines are particularly noxious. The preparation of l-benzyl-l-nitroso-3-nitroguanidine is typical of the techniques used. 

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. 

According to these authors, nitrosoguanidine is prepared by the reduction of nitroguanidine with zinc dust in a neutral medium, in the presence of ammonium chloride at room temperature (below 20-25°C). The product is filtered off together with a precipitate of zinc oxide and zinc salt, from which it is then extracted with hot (65°C) water. Nitrosoguanidine crystallizes when the solution is cooled to 0°C. The yield is about 50%. 

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 ... 

Guanidine nitrate is soluble in alcohol and water. It is the precursor compound in the synthesis of - Nitroguanidine. It is prepared by fusing dicyanodiamide with ammonium nitrate. 

Preparation of Nitroguanidine. Twenty-five cc. of 61% aqueous sulfuric acid is poured upon 20 grams of dicyandiamtde contained in a 300-ce. round-bottom flask equipped with a reflux condenser. The mbe-ture warms up and froths considerably. After the first vigorous reaction has subsided, the material is heated for 2 hours in an oil hath at 140 (thermometer in the oil). The reaction ma.ss, chilleil in a freezing... 

Hydrazine salts have been prepared by the action of hypochlorites on ammonia (1) or urea (2) by the hydrolysis of salts of sulfohydrazimethylene disiilfonic acid (3) by the hydrolysis of triazoacetic acid (4) by the reduction of diazoacetic ester (5) by the reduction of nitroguanidine followed by hydrolysis (6) by the reduction of the nitroso derivatives of hexamethylene tetramine (7) by the reduction of nitrates or nitrites with zinc in neutral solution (8) by the action of sodium bisulfite on hyponitrous acid followed by reduction (9) by the reduction of K2S03N202 (10) by the action of ammonia on dichlorourea (11) by the reduction of nitrosoparaldimin (12) by the action of copper sulfate on ammonia at high temperatures (13) by the reduction of methylene diisonitrosoamine (14) by the hydrolysis of the addition product of diazoacetic ester and fumaric or cinnamic esters (15). 

Similar to the preparation of some of the oxygen analogs discussed in Section 9.09.9.1.1, thiadiazine 125 is synthesized in low yield starting from A -nitroguanidine 217 with formaldehyde and sodium sulfide in the presence of HCl. Alternatively, 125 is synthesized in two steps from 178 via the cyclic intermediate 123. Alkylation of 123 with 6-chloropyridine-3-ylmethyl chloride gave 125 in 23% yield and the dialkylated thiadiazinane 127 as a byproduct in 19% yield (Scheme 38) <2001MI165>. 

Preparation of nitroguanidine was developed by Jousselin. The German Army replaced picric acid with TNT. 

The simplest method for the preparation of 2-(nitromimo)imidazolidine is the heating of nitroguanidine with ethylenediamine in water. 

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