Janovsky test

Janovsky Test. Color reactions produced by treating aromatic nitro compds with hot" cold alcoholic NaOH or KOH and acetonic NaOH solns. A table of color reactions of some nitro compds is given in Ref 2. See Janovsky s Reagent under COLOR REACTIONS and COLOR REAGENTS in Vol 3 of Encycl, p C405-R... 

The reaction of 1,3-dinitrobenzene with alkaline acetone to give a purple-coloured solution was noted as early as 1886 by Janovsky and Erb and is now known as the Janovsky reaction . Since then strong colours have been observed from a variety of active methylene compounds and the reaction is used as a test for them. Much of the literature has been summarized by Canback (1949a, 1949b), who suggested the structure 42, and more recently by Pollitt and Saunders (1965). Chemical and spectroscopic evidence is in support of formula 42 and dark purple crystals have been prepared (Gitis and Kaminskii, 1963, 1964 Kimura et al., 1965). Oxidation with hydrogen peroxide in acidic... 

The Janovsky reaction became an important analytical test which could be used to detect both reagents di- or trinitro rompounds or ketones and aldehydes. The modification of the reaction consisting in the use of m-dinitrobenz-ene as a test for 17-ketosteroids is sometimes called the Zimmerman reaction [15,56). 

The pharmacopoeia test is quite unique in that a content of nitrate under the conditions given will react with nitrobenzene to give m-dinitrobenzene, which then will react with acetone to form a colored product indication a positive reaction. The methodology of this second reaction was first described in literature in 1939 by Pesez and is based on the Janovsky reaction that for many years was widely used for the colorimetric/photometric determination of substances sometimes referred to as methyl ketones. ... 

In circumstances where the m-dinitrobenzene is in excess, it will oxidize the Janovsky product to the Zimmermann product (Figure 3.25.5). There will be an alkaline environment in equilibrium between the Zimmermann form and the Janovsky form. If the ketone is in excess, as in the present test, the Janovsky product will be the predominant form. ... 

ISO/ASTM (2004) Standard practice for use of the alanine-EPR dosimetry system. ISO/ASTM standard 51607, American Society for Testing and Materials, http //www.astm.org Janovsky I (1985) High-dose dosimetry. In Proceedings of symposium, IAEA, STI/PUB/671, International Atomic Energy Agency, Vienna, p 307 Janovsky 1, Miller A (1987) Appl Radiat Isot 38 931 Janovsky I, Hansen J, Cemoch P (1988) Appl Radiat Isot 39 651... 

The following reactions were used for the industrially important benzene hexachloride with zinc or, better, magnesium, in glacial acetic acid, benzene hexachloride is dechlorinated to benzene, which can then be detected by the Janovsky or Mohler color reaction (p. 356) (18—20). Also, the test proposed for DDT, i.e., nitration and the reaction of the nitro compoimds formed with methanolic sodium hydroxide, is recommended (21). Other tests recommended are the reaction of DDT with sulfuric acid in acetic acid (22), the reaction with xanthydrol, alkali, and pyridine (23), and the reaction with benzene according to the Friedel-Crafts procedure (24). 

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