Benzeneazo-«-naphthol

Required Benzeneazo-naphthol from above experiment methylated spirit, 100 ml. stannous chloride, 22 g. hydrochloric acid, 60 ml. 

C) Preparation of Sudani (Benzeneazo- -Naphthol). Dissolve 2.2 g of /3-naphthol by heating in 5 ml 6 iV sodium hydroxide solution and 5 ml of water when dissolved add 10 ml of water and cool to about 5°. Add 15 ml (0.015 moles) of benzenediazonium chloride slowly while stirring. Allow to stand in the cold later, filter the dye, wash repeatedly with water, press with a cork, and remove to a paper to dry. The sdeld is about 3 g. 

The only practical method of preparing 1,4-aminonaphthol is from a-naphthol through an azo dye, the nitroso compound not being readily available. The majority of investigators have reduced technical Orange I with stannous chloride Mi.is.is.ir.is by the procedures discussed above, and benzeneazo-a-naphthol has been reduced by the same reagent. In order to make possible the use of crude, technical a-naphthol a method has been developed for the preparation of the benzeneazo compound, its separation from the isomeric dye coming from the d-naphthol present as well as from any disazo compound by extraction with alkali, and the reduction of the azo compound in alkaline solution with sodium hydrosulfite. The process, however, is tedious and yields an impure product. 

The moist benzeneazo-a-naphthol is next transferred to a 5-1. wide-mouth bottle or a 2-gal. crock equipped with a mechanical stirrer and containing 3 1. of 10 per cent sodium hydroxide solution. The mixture is stirred for ten minutes to insure solution of the dye, and then filtered. The insoluble solid is stirred up with 500 cc. of xo per cent sodium hydroxide, filtered again and washed with water. The solid, which weighs 10-90 g, consists mainly of the 2,4-disazo derivative (m. p. 197-198°), together with any benzeneazo-/3-naphthol that may be present. 

Azobenzene. o-Azotoluene. m-Azotoluene p-Azotoluene o-Azophenetole p-Azophenetole Benzeneazo-o-cresol a-Benzeneazo- P-naphthol P-Benzeneazo-a-naphthol 4-Benzeneazo- a-naphthol Benzeneazodiphenylamine a-Benzeneazo- P-naphthylamme 4-Benzeneazo- a-naphthylamme p-Aminoazobenzene p-Dimethylaminoazobenzene. p-Hydroxyazobenzene. ... 

The phenomenon of azo—hydrazone tautomerism is firmly established75 in the benzeneazo-phenol, -naphthol, and -anthranol series, the azo form predominating in the first of these (65), the hydrazone form in the second (66), whilst the third exists exclusively in the hydrazone form (67). The situation is less clear in the analogous o-aminodiarylazo series. Thus, whilst it is known that o-aminoazobenzene (68) exists exclusively in the azo form, it has not been established whether... 

Nitrazine yellow (0-1 %). Dissolve 0-1 g of nitrazine yellow (2,4-dinitro-benzeneazo)-l-naphthol-4,8-disulphonic acid, disodium salt, (Colour Index 14890) in 100 ml water. 

BENZENEAZODIMETHYKANILINE see DOT300 BENZENE-1-AZO-2-NAPHTHOL see PEJ500 BENZENEAZO-p-NAPHTHOL see PEJ500 l-BENZENEAZO-2-NAPHTHYLAiMlNE see FAG130 1-BENZENE-AZO-P-NAPHTHYLAMINE see FAG130 p-BENZENEAZOPHENOL see HJFOOO BENZENE, l,3-BIS(ISOCYANATOMETHYL)-(9CI) see XIJOOO... 

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