Ammonium picrate preparation

VI. Uses. During the latter part of the nineteenth century and the early part of the present century, PA was widely used as the main expl charge of projectiles and bombs. This is no longer true, Indeed PA per se is hardly used as an expl. Its current limited expl-related use is primarily in the preparation of Explosive D (Ammonium Picrate) and Lead Picrate. It also finds some use as an intermediate in the manuf of dyes. There is some patent literature on the use of PA as a catalyst for polymerizations. For example, PA is claimed as catalyst in polybutadiene polymerizations (Ref 40), and for the prepn of an isobutylene-5-methyl-1,3,6 hepta-trieie copolymer (Ref 38)... 

However, more-rigorous treatment (5% acetic acid, 100°C, 17 hours) opened the imidazole ring and produced /V -cyclohexyl-a-formylaminoacetamidine (57), characterized as the crystalline picrate. Amidine 57 produced no dye in the Bratton-Marshall assay. The same behavior can be expected from AIR (46), although the product of hydrolytic ring-opening was not actually isolated. On the other hand, it was observed that a solution of AIRs (0.2 mM in 0.01-M ammonium hydroxide) prepared by biosynthesis, when stored at 4°C, did not change appreciably within a day. A decrease in the concentration of AIRs of about 30% occurred within a month. 

Designolle and Brugere suggested that picrate salts could be used as a propellant, while in 1871, Abel proposed the use of ammonium picrate as an explosive. In 1873, Sprengel showed that picric acid could be detonated to an explosion and Turpin, utilizing these results, replaced blackpowder with picric acid for the filling of munition shells. In Russia, Panpushko prepared picric acid in 1894 and soon realized its potential as an explosive. Eventually, picric acid (1,2) was accepted all over the world as the basic explosive for military uses. 

During World War II, an improved process was developed for producing petroleum naphthas ensuring unlimited quantities of toluene. Purification techniques were improved for TNT. Composites mixtures of TNT-PETN, TNT-RDX, TNT-tetryl, TNT-ammonium picrate, TNT aluminium, etc., were prepared. 

Picramic acid, red needles, m. p. 169°, may be prepared by evaporating ammonium picrate in alcohol solution with ammonium sulfide. 

Ammonium picrate is soluble in water, alcohol and acetone, and is practically insoluble in ether. It is prepared by saturating an aqueous solution of picric acid with ammonia a red form is formed first which passes into the stable yellow form in the presence of water vapor, on prolonged storage or by recrystallization from water. Ammonium picrate has been employed as an explosive in military charges. 

Guanidine picrate is sparingly soluble in water and alcohol. It is prepared by mixing solutions of guanidine nitrate and ammonium picrate. 

Summary Ammonium picrate is prepared by treating picric acid with ammonia in benzene solution. The ammonium picrate precipitates and is collected by filtration. Commercial Industrial note Part or parts of this laboratory process may be protected by international, and/or commercial/industrial processes. Before using this process to legally manufacture the mentioned explosive, with intent to sell, consult any protected commercial or industrial processes related to, similar to, or additional to, the process discussed in this procedure. This process may be used to legally prepare the mentioned explosive for laboratory, educational, or research purposes. 

Sodium and potassium picrate were prepared from picric acid and the alkali carbonate. They were purified by recrystallizing from water. Tetraethyl ammonium picrate was prepared by mixing equivalent quantities of tetraethyl anunonium iodide and sodium picrate solution and recrystallizing from water. 

TNT lelryl, TN T ammonium picrate. TNT aluminium, cfc. . wore prepared. ... 

Guanidine gives a positive biuret reaction (p. 271), the reaction with sodium pentacyanoammoferroate (p. 361) (13) similar to urea, the reaction with thymol and hypochlorite (14), and the reaction with sodium 1,2-naphthoqui-none-4-sulfonate (p. 320) (15). It is also precipitated with Nessler s reagent (p. 211). Guanidine gives a weakly soluble picrate, which can be prepared by precipitation of a neutral aqueous guanidine solution with an aqueous 1% ammonium picrate solution. 

Picrates, Many aromatic hydrocarbons (and other classes of organic compounds) form molecular compounds with picric acid, for example, naphthalene picrate CioHg.CgH2(N02)30H. Some picrates, e.g., anthracene picrate, are so unstable as to be decomposed by many, particularly hydroxylic, solvents they therefore cannot be easily recrystaUised. Their preparation may be accomplished in such non-hydroxylic solvents as chloroform, benzene or ether. The picrates of hydrocarbons can be readily separated into their constituents by warming with dilute ammonia solution and filtering (if the hydrocarbon is a solid) through a moist filter paper. The filtrate contains the picric acid as the ammonium salt, and the hydrocarbon is left on the filter paper. 

Several explosive salts including the acetylide, azide, borate, bromate, chlorate, chromate, iodate (and ammonium iodate double salt), nitrite, perchlorate (and ammonium perchlorate double salt), periodate, permanganate, picrate and trinitrobenzoate were prepared. The 3 latter salts and the acetylide, azide and bromate are impact-sensitive detonators [1], It appears probable that many of the explosively unstable compounds [2], formed in various ways from interaction of mercury or its compounds with ammonia or its salts, may have the common polymeric structure now recognised for Millon s base [3], This is a silica-like network of N+ and Hg in 4- and 2-coordination, respectively, with OH and water in the interstitial spaces. Individually indexed compounds are Poly(dimercuryimmonium acetylide)... 

Trinitrophenetol or ethyl picrate, m.p. 78°, is prepared by the same methods as trinitroanisol. The explosive properties of the two substances have been studied by Desparmets and Calinaud, and by Desvergnes,72 who has reported the results of the earlier workers together with data of his own and discussions of methods of manufacture and of the explosive properties of mixtures with picric acid, ammonium nitrate, etc. Drop test with a 5-kilogram weight were as follows ... 

Excellent examples of this reaction are found in the preparations of acetamidine (91%) and nicotinamidine (60%). The conversion is accomplished by treatment of the imino ester hydrochloride with alcoholic ammonia or by the action of ammonium chloride on the free imino ester. The amidines are frequently isolated as salts such as the sulfates or picrates. N-Substituted amidines result when amines are used in place of ammonia. ... 

Ciystallise it from MeOH/EtOH (1 1). Separation from normal a//o-isomer can be achieved by crystallisation of the copper salts [see Levine Biochemical Preparations 8 114 1961]. Separation from proline is achieved via the ciystalline picrate, CdCl2, or acid ammonium rhodanate salts [see Greenstein Winitz The Chemistry of the Amino Acids J. Wiley, Vol 3 p 2182 1961, Kapfhammer Mohn Z Physiol Chem 306 76 1956], [Beilstein 22/5 V 7.]... 

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