DE423090C - Process for the preparation of aminoazo compounds - Google Patents

Description

Process for the preparation of aminoazo compounds. It was found, that by the action of m-diazobenzaldehydes on aromatic amines capable of coupling in z. B. acidic or neutral aqueous solution or suspension, the previously unknown 3-Aldehydhenzolazoarylamine or the corresponding Diazoaminoverbindungen, which pass into the former by rearrangement, arise. This course of the reaction was in With regard to the great reactivity of the aldehyde group, especially in the presence of aromatic bases and the well-known rapid conversion of m-diazo-lenzaldehyde salts even at low temperatures in in-oxybenzal, dehyd (cf. e.g. Journal f. pr. Ch.56. Pages 97 and 117) cannot be foreseen and must be described as surprising will.

The new; -Aldehydebenzolazoarylamine are either already usable Dyes that have significant advantages over the corresponding aldehyde-free Bring dyes, or important building blocks for different classes of dyes special technical effects.

The described reaction is very expandable in accordance with the known formation of aminoazo compounds and allows all benzaldehyde azoarvlamines with a free aldehyde group y in the 1M position to the azo group to be represented according to the following general scheme: - R - CHO indicates the use of m-aminobenzaldehyde, its derivatives and substitution products R1 - NHZ or the use of aromatic amines capable of coupling mono- and diamino compounds) and their derivatives and substitution products, such as. B. in addition to aniline, the toluidines, aminocresyl ethers, m-phenylenediamine, m-tolylenediamine, acetyl-m-phenylenediamine, a-naphthylamine and others

The implementation essentially follows that of the benzene azoarvlamines at. When using certain bases, such as. B. aniline or o-toluidine first the so-called diazoamino compounds, which in a known manner can be rearranged to the aminoazo compounds.

Examples. r. 11.2 g of m-aminobenzaldehyde (anhydro compound) will be diazotized with 6.9 g of Natriu.mnitrite in hydrochloric acid solution under good cooling and with a strong hydrochloric acid Solution of 10.7 g of m-toluidine below o ° slowly united; the solution first turns light yellow '- and contains the diazoamino compound, which can be isolated in a known way as yellow crystal powder. By After stirring at 10 to 15 °, the color of the solution changes to red-orange, and it Partly the corresponding aminoazo compound already separates as hydrochloric acid Salt out. The deposition can be completed by blunting the acid. The 3 Aldehydbenzolazo-d .'-amino-2'-methylbenzene is a red-orange colored body, fairly easily soluble in hot diluted alcohol, from which it turns into red-brown needles crystallized. Melting point 167 ° with decomposition. It is produced by sulfating a real orange-yellow wool dye.

2. 12.1 g of m-aminobenzaldehyde in the form of dough are, as usual, under good cooling and dianotized at 0 to 5 ° with 14 g of 2-aminoq.-cresol methyl ether in hydrochloric acid solution coupled. After the acid is blunted with soda, the dye falls the end; it is then filtered and washed neutral with water. The new aminoazo body (3-Aldehydbenzolazo-2-methyl- [-amino-5-methoxybenzene) is an orange-yellow, in Water-insoluble powder, which is in concentrated sulfuric acid with dissolves deep yellow-red color. Sulfation gives a wool that is really orange-red coloring acidic wool dye.

3. I 1.2 g of m-aminobenzaldehyde (anhydrous compound) are dianotized with 6. g of sodium nitrite, as previously described. Then the filtered solution is stirred into a solution of 10.8 g of m-phenylenediamine in 175 cc of hydrochloric acid (10%) at 0 to 5 °, after the red-orange solution has been stirred for another quarter of an hour, sodium acetate slowly becomes binding the excess hydrochloric acid added. After stirring for 1 to 2 hours, the formation of the dyestuff is complete, the dyestuff, which has already partially precipitated out as a hydrochloric acid salt, is salted out, dissolved in water, the base is precipitated with alkali, washed and dried. It is a yellow-brown crystal powder and stains cotton stained with tannin and pretzel tartar yellow-brown; the dyeings, like those of the dye made from m-aminobenzaldehyde and n-toluylenediamine (1, 2, q.), in contrast to the known chrysoidine (aniline m-tolylenediamine), show excellent washfastness.

q .. If in example e the m-phenylenediamine is replaced by 12.2 g 2 # 6-Diaminotoluene, sc gives a similar coloring of very good color Washfastness.

5. 11.2 g of m-aminobenzaldehyde (anhydro compound) are under the described precautionary measures, dianotized and at 0 to 5 ° with a solution of 14.3 a-naphthylamine in 100 cc water and 140 cc hydrochloric acid (3%) unified. The dye formation is soon complete by stirring at 20 to 25 °. The precipitated dye is filtered and, after removal of the acid, with water washed neutral. It is a brown powder that is insoluble in water dissolves in concentrated sulfuric acid with purple color by diazotizing and coupling of the diazo compound with ß-oxynaphthoic anilide results in a water-insoluble one black-violet dye, which after sulphonation of wool from an acid bath in alkaline, Dyes water and washfast purple tones. With o = oxycarboxylic acids he can easily to Leuke compounds of oxytriarylmethanazo dyes in concentrated sulfuric acid condense. By dianotation and coupling with ß-oxynaphthoic acid-ß-naphthalide the result is a black dye that is insoluble in water.

Claims (1)

PATENT CLAIMS Process for the preparation of aminoazo compounds, characterized by the action of m-diazobenzaldehydes on aromatic compounds capable of coupling Mono- or diamines.