Dipicrylamine hexanitrodiphenylamine

Potassium is selectively precipitated by nitrated aromatic amines36). The use of dipicrylamine (hexanitrodiphenylamine) as a precipitant for potassium in sea water has been extensively studied. In comparison to others this salt is only slightly soluble in aqueous solutions (0.898 g/1 at 21 °C). The magnesium, calcium, and sodium salts have a much higher solubility. The involved reaction is... 

Hexanitrodiphenylamine (m. p. 243-245°C) was first mentioned in the chemical literature in 1876 and as long ago as 1891 Haussermann [21] drew attention to its explosive properties. The product is known under the names of Dipicrylamine, Hexyl, Heksyl, Hexamite, Hexamin, etc. 

SYNS AURANTIA BIS(2,4,6-TRINITRO-PHENYL)-AMIN (GERMAN) C.1.10360 DIPHENYLAMINE, HEXANITRO- DIPICRYLAMINE DIPICRYLAMINE (DOT) DIPIKRYLAMIN DPA ESANITRO-DIFENILAMINA (ITALIAN) 2,2, 4,4, 6,6 -HEXANITRO-DIFENYLAMIN HEXANITRODIFENYLAMINE (DUTCH) HEXANITRODIPHENYLAMINE HEXANITRODIPHENYLAMINE (FRENCH) 2,2, 4,4, 6,6 -HEXANTTRODIPHENYLAMINE 2,4,6,2, 4, 6 -HEXANTTRODIPHENYLAMINE HEXYL (GERMAN, DUTCH)... 

In contrast to its parent substance, (weakly basic colorless diphenyl-amine), hexanitrodiphenylamine (I) is an acid which dissolves in sodium hydroxide or carbonate to produce orange-red solutions. This color change is due to a change in structure. Hydroxyl ions convert the baso-form of dipicrylamine (I) into the aci-form (II), in which a continuous chain of conjugated double bonds effects the deepening of color. ions convert the orange-red aci-form to the bright yellow water-insoluble baso-form ... 

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