Phenyldiazonium solution

Sulfophenylmethylpyrazolone, equivalent to 26 grams (0.1 mole) of 100 per cent material, is dissolved in 120 cc. water containing 6 grams of soda ash, and 30 grams of sodium acetate is added to the solution. The solution is cooled to 0°C. and mixed with a phenyldiazonium solution prepared from 9.3 grams of aniline. The mixture is stirred until a... 

A solution of 0.01 mole (1.44 grams) of jS-naphthol in 2 cc. 30 per cent sodium hydroxide is diluted to 400 cc., and 25 cc. 10 per cent soda ash is added. Ice-cold 0.1 N phenyldiazonium solution is added from a graduated cylinder or a cooled burette until a drop of the re-... 

Phenyldiazonium chloride and other similar diazonium compounds are very soluble in water, are completely insoluble in ether and other organic solvents, and are completely dissociated in aqueous solution to organic cations and inorganic anions (e.g., chloride ions) a convenient formulation is therefore, for example, CjHjNj+CP. 

When an aqueous solution of phenyldiazonium chloride or of p-tolyl-diazonium hydrogen sulphate is treated with an equivalent of potassium iodide and warmed on a water bath, iodobenzene or />-iodotoluene is formed in good 3deld ... 

Chlorobenzene. Prepare a solution of phenyldiazonium chloride from 31 g. (30 -5 ml.) of aniUne, 85 ml. of concentrated hydrochloric acid, 85 ml, of water, and a solution of 24 g. of sodium nitrite in 50 ml. of water (for experimental details, see Section IV,60). Prepare cuprous chloride from 105 g. of crystallised copper sulphate (Section 11,50,1), and dissolve it in 170 ml. of concentrated hydrochloric acid. Add the cold phenyl diazonium chloride solution with shaking or stirring to the cold cuprous chloride solution allow the mixture to warm up to room temperature. Follow the experimental details given above for p-chlorotoluene. Wash the chlorobenzene separated from the steam distillate with 40 ml. of 10 per cent, sodium hydroxide solution (to remove phenol), then with water, dry with anhydrous calcium chloride or magnesium sulphate, and distil. Collect the chlorobenzene (a colourless liquid) at 131-133° (mainly 133°), The yield is 29 g. 

Assemble the apparatus shown in Fig. 1 V, 67, 1 this is self-explanatory. The distilling flask has a capacity of 250 ml. and the beaker contains 150 ml. of 10 per cent, sodium hydroxide solution. All corks must fit well and should be coated with paraflSn wax (by dipping into molten wax, and allowing to drain). Place half of the yield of the dry phenyldiazonium fluoborate in the distilling flask. Heat the solid gently with a small luminous flame at one point near its surface until decomposition begins withdraw the flame and allow the reaction to continue... 

Concurrently with the preparation of the phenyldiazonium chloride solution, prepare a cold suspension of sodium arsenite. Place 250 ml. of water in a 3-htre round-bottomed flask equipped with a mechanical stirrer. Heat the water to boding, add 125 g. of anhydrous sodium carbonate, and, as soon as the carbonate has dissolved, introduce 62 5 g. of pure arsenious oxide and 3 g. of crystallised copper sulphate with stirring. When all the solids have dissolved, cool the solution with stirring under a stream of tap water until the temperature has fallen to 15°. 

Attention has previously (see Diazonium Sails) been drawn to the fact that unless an excess of hydrochloric (or mineral) acid is used in the diazotisation process, coupling occurs between the diazonium salt and the amine to give diazoamino compounds. Thus phenyldiazonium chloride and aniline yield diazoaminobenzene. This substance may be conveniently prepared by dissolving two equivalents of aniline in three equivalents of hydrochloric acid, and adding one equivalent of sodium nitrite in aqueous solution followed by two equivalents of sodium acetate ... 

Phenylhydrazine may be prepared by reducing phenyldiazonium chloride solution with excess of warm sodium sulphite solution, followed by acidification with hydrochloric acid, when the hydrochloride crystallises out on cooling. Treatment of the latter with excess of sodium hydroxide solution liberates the free base. The reaction is believed to proceed through the following stages —... 

It may also be prepared by the reduction of phenyldiazonium chloride with the calculated amount of a solution of stannous chloride in hydrochloric acid, but the yield is not so high as that obtained by the above sulphite method ... 

Phenyldiazonium Perbromide.—To a fresh ice-cold solution of one of the solid diazonium salts, prepared as described above, or to the diazo-solution from 2 g. of aniline, there is added the solution of 1-5 c.c. of bromine in 15 c.c. of potassium bromide solution (25 per cent), with ice cooling, until precipitation of dark-coloured oil ceases. The aqueous solution is then decanted when the residual perbromide is washed a few times with ice-water it crystallises. 

Phenyldiazonium mtroformate. Nitroform derivative (XIII) is of particular interest among derivative diazonium salts. It was prepared by Ponzio [21] who reacted the potassium salt of trinitromethane (nitroform) with an aqueous solution of phenyldiazonium acetate ... 

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