Picrates inorganic

Pikratol. Ger for Ag Picrate. See in this Vol under Picrates, Inorganic... 

Nonaqueous titrimetry has been applied to detn the purity of inorganic stearates, nitrates, RDX, Aram Picrate, Tetryl, Haleite, TNG, K nitrate in M-8 propint and NGu (See Vol 1, A165-R Vol 3, D102-L C625-R to C626-L Vol 6, G154-L G161 Refs 30, 30a, 30b, 30c, 30d, 30c, 30f, 30g, 36, 59 61)... 

The salts and additive compds of Picric Acid (PA) are usually included under picrates. For convenience, inorganic and organic picrates will be described separately... 

Plastomenites. Propints, patented in Ger by Guttler in 1889—90, consisting of NC, Nitro-lignine, Nitrosugar, Nitrostarch, etc, gelatinized by the addition of nitrated aromatic compds such as benz, toluene, phenol, naphthalene, etc. Inorganic nitrates, chlorates, chromates, picrates, etc, could be added to the mixt... 

During the traditional qualitative inorganic analytical procedure, samples containing the lead and salicylate radicals can lead to the formation and possible detonation of lead picrate. This arises dining evaporation of the filtrate with nitric acid, after precipitation of the copper-tin group metals with hydrogen sulfide. Salicylic acid is converted under these conditions to picric acid, which in presence of lead gives explosive lead picrate. An alternative (MAQA) scheme is described which avoids this possibility. 

Metal salicylates are occasionally incorporated into mixtures of unknowns for qualitative inorganic analysis. During the conventional group separation, organic radicals are removed by evaporation with nitric acid. When salicylates are present, this can lead to formation of trinitrophenol through nitration and decarboxylation. This may react with any heavy metal ions present to form unstable or explosive picrates, if the evaporation is taken to dryness. The MAQA alternative scheme of analysis obviates this danger. 

Nitrated cresols form a number of salts, by interaction with inorganic compds. These salts are called Cresylates. They possess props similar to those of Picrates, except that they are less powerful less sensitive expls than Picrates. Colver (Ref 4) gives a fairly complete list of these compds, and Kast (Ref 3) describes their props. Some of the more important Cresylates are Aluminum Trinitrocresylate (Basic), HO.A1-(C H4N30 )2+ 5H20 pale reddish ndls, mp defgr above 100° sol in w ale resembles the corresponding picrate in other props (Refs 1 4). 

Complexation of inorganic cations such as alkaline or alkaline earth metals by macrocyclic polyethers produces large, lipophilic cationic metal-macrocycle complexes that are readily soluble in nonpolar solvents such as benzene, toluene and haloalkanes. In order to maintain charge balance, the cationic complex has an associated counter anion. In an immiscible two-phase liquid system, such as a mixture of chloroform and water, the anion is necessarily pulled into the organic phase as the cationic complex crosses the phase boundary. A simple illustration of this principle is obtained by addition of a chloroform solution of [18]crown-6 to an aqueous solution of potassium picrate (potassium 2,4,6-trinitrophenolate). The yellow colour of the picrate anion is transported rapidly into the contiguous (physically in contact) chloroform phase upon agitation (Figure 3.43). 

Qualitative inorganic analysis of compounds containing lead and salicylate radicals can lead to the formation of explosive lead picrate. This occurs due to conversion of salicylic acid to picric acid during evaporation with nitric acid.21... 

Generally the use of lead as a material for construction of a picric acid plant is avoided, except in Great Britain and in the U.S.A. where it is used for the parts of installation which are also in contact with inorganic acids. The latter, being strong acids, are assumed to inhibit the formation of lead picrate. 

Compounds are not always formula-indexed under their own formulas. This is a departure from the ideal, but is reasonable. The interest in a salt of a complex organic acid is likely to be mainly in the acid.. It is more valuable to have the record of the salt under the formula of the acid for the use of searchers looking up the acid. In Chemical Abstracts entries under their own formulas are made for all strictly inorganic and strictly organic compounds, both addition compounds and true reaction derivatives (esters, acetals, hydrazones, oximes, picrates, semi-carbazones, etc.) the diethyl ester of malonic acid is found under C7H]204. 

Straight-phase ion-pair HPLC has been applied for the analysis of alkylamines (see Chapter 15) using a stationary phase loaded with an aqueous picrate or naphtalenesulfonate solution. These counter-ions also improve the detection limit of poorly UV-absorbing compounds. Also inorganic counter-ions, such as bromide and perchlorate, have been used in straight phase ion-pair chromatography (see Chapter 15). 

Salts and organic esters of some inorganic acids. In addition to the dangers of perchlorate salts, other salts such as nitrates, azides, diazo salts, organic nitrates, organic azides and picrates (see above) can be hazardous, and due care should be taken when these are dried. Large quantities should never be prepared or stored for long periods. 

Experimental studies of ions association became feasible with the advent of relaxation techniques, picosecond spectroscopy, and ESR spectroscopy. Pioneering work in this field was done by Eigen, e.g.298), who studied the association of inorganic ions in aqueous solutions. Recent development of field-modulation technique335) allows for detailed investigations of ions association in low polarity media. This technique requires very low concentrations of ions in the investigated systems - a condition met by solutions involving low polarity solvents. Its application to systems such as tetrabutyl ammonium picrate in... 

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