Azo-p-nitrobenzene

Fig. 3.127. Representative coupling reaction between PNBD and the sodium salt of 2-naphtol-6-sul-phonic acid to yield the 6-sulphonate-2-naphtol-l-azo-p-nitrobenzene azo dye. Reprinted with permission from C. Bravo-Diaz et al. [177],...

Diazo violet o-p-Dihydroxy-azo-p-nitrobenzene 10.1-12.0 yellow - violet Kolthoff... 

The first measurement of clay acidity was reported by Walling (72), who found that an acid-washed bentonite clay of the montmorillonite group imparted the acid color to p-nitrobenzene-azo(p -nitro) diphenyla-mine, which has a pKa of 0.43. At least part of this acidity, however, was thought to result from residual acid from the acid wash. 

Alternative names are p-nitrobenzene-azo-1 8-dihydroxynaphthalene-3 6-disulphonic acid and Chromotrope 2B (the latter is the sodium salt). 

The reagent consists of a 0 025 per cent solution of p-nitrobenzene-azo-resorcinol in m sodium hydroxide. 

Among the azo dyes we may include o-methyl red, naphthol orange, curcumin, o-p-dioxyazo-p-nitrobenzene, and tropeolin 0 (sodium sal) of resorcin-azo-benzenesulfonic acid). 

Diethylamine acetate Pyridiniiim salt T etramethylammonium acetate, Tetraethyl-ammonium-Piperidinium acetate Isoxazolium salts Trialky loxonium salt Amidinium salts Ketenimines Diazo compounds Diazomethane, Phenyl-diazomethane K-methy Idiazotate Hexamethylenetetramine Azo compounds Azodicarboxamide ROOC-N N-COOR A zodiisobuty ronitrile T riazenes Azidinium salts p-Nitrobenzene-diazonium sulfate Sulfanilic acid, diazotized... 

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