2- Naphthalenediazonium chloride

The direct method 2-Naphthalenediazonium chloride solution 252 2-Naphthylamine (143 g, 1 mole) is added to a mixture of concentrated hydrochloric acid (450 ml) and water (500 ml). The resulting suspension of amine hydrochloride is cooled to 5° by addition of ice (500 g). Then solid sodium nitrite (ca. 69 g) is added, with vigorous stirring, until presence of a slight excess is indicated by a color on starch-iodide paper. Additional ice (ca. 600 g) is added gradually during the preceding reaction so that the temperature does not exceed 5°. At the end of the reaction small amounts of insoluble matter are filtered off. 

In 1902 Mai discovered that aniline, p-toluidine, and benzidine could be deaminated by reducing their diazonium chlorides with 10% aqueous hypophosphorous acid. Benzene, toluene, and biphenyl were obtained in 40, 67, and 60% yields, respectively. From a-naphthalenediazonium chloride, naphthalene was produced very slowly and in unstated yield.8 The reaction was not investigated further, and the encouraging results that had been obtained did not give rise to widespread use of hypophos-... 

Various aromatic amines, phenols, and compounds containing active methylene groups can be titrated with arenediazonium salts, from which 4-bromo-l-naphthale-nediazonium chloride seems to be the most widely applicable titrant. Compounds that react slowly with arenediazonium salts can be determined by back-titration when the excess of arenediazonium salt is back-titrated with either sodium tetraphenylborate or 2,4-diaminotoluene. Indirect determination is useful for secondary amines, which react with arenediazonium ions to form triazenes. The determination of diazonium salts of ampholytic character is based on the reaction of these salts with l-phenyl-3-methyl-5-pyrazolone, the excess of which is titrated with 4-bromo-l-naphthalenediazonium chloride solution. 

An H, C and spectral investigation of four 1-naphthylazo compounds 39-42, which were prepared by coupling 1-naphthalenediazonium chloride with the appropriate passive components, was reported . 

Naphthalene, 10,14 16, 68 jS-Naphthalenediazonium chloride, mercuric chloride compound, 12, 46, S5il )9°... 

Hydroxy-2-nitrobenzaldehyde, 2688 4-Hydroxy-3-nitrobenzenesulfonyl chloride, 2139 2-Hydroxy-6-nitro-1 -naphthalenediazonium-4-sulfonate, 3234 2-Hydroxy-2-phenylacetophenone, Benzoin, see 2-Hydroxy-1,2-diphenyletha-... 

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