Janowski reaction

It has been known for a long time that polynitroaromatic compounds produce colored products in contact with aUcafis [1]. These color reactions have been extensively used for the identification of nitroaromatic explosives. In the Janowski reaction [7], a solution of the polynitroaromatic compound (di- or trinitroaromatic) in acetone is treated with concentrated aqueous KOH solution. 1,3,5-Trinitrobenzene (TNB) and 2,4,6-trinitrotoluene (TNT), treated with 30% aqueous KOH, produced violet-red and red colors, respectively. Many variations of the Janowski reaction were reported, using KOH or NaOH in aqueous or ethanoHc solutions as reagents, and dissolving the explosives in acetone, ethanol or acetone-ethanol mixture [3,8]. The reaction was used both for spot tests and for spraying TLC plates [9]. 

A field test for the detection of TNT in contaminated soils (e.g., near ammunition plants) was based on the color reaction between TNT and alkalis (the Janowski reaction [7]) [26]. A few milligrams of the suspected soil are placed on filter paper and sprayed with 1 M NaOH acetone (1 1). A red color indicates the possible presence of TNT. Detection limits were reported to be 2-50 mg of TNT per 1 kg of soil, depending on the type of soil. The same group [55] used the oxidation of DPA in concentrated H2SO4 as the basis of a field test for nitrate esters and nitramines in soil. 

A polynitroaromatic compound such as TNT reacts with an alkali such as potassium hydroxide to give an intensely coloured Jackson-Meisenheimer reaction product. When this reaction takes place in a ketone solution such as acetone, it is known as Janowsky reaction. In this paper, we slightly modify the approach by replacing acetone with DMSO. We have chosen DMSO as the solvent in our system because the DMSO droplets would be immiscible with the surrounding silicone oil while acetone would mix with the silicone... 

Vincent GM, Janowski M, Menlove R. Protamine allergy reactions during cardiac catheterization and cardiac surgery risk in patients taking protamine-insulin preparations. Cathet Cardiovasc Diagn 1991 23(3) 164-8. 

Z. Chen, S. Duncan, K. K. Chawla, M. Koopman, and G. M. Janowski, Characterization of interfacial reaction products in alumina frber/barium zirconate coating/alumina matrix composite. Mat. Char., 48 305-314 (2002). 

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