DE208343C - - Google Patents

Description

IMPERIAL

PATENT OFFICE.

PATENT LETTERING

- JVl 208343 CLASS 22 e. GROUP

Process for the preparation of vat dyes,

Patented in the German Empire on September 20, 1907.

It has been found that when treating the in alkaline solution by chlorine liquor obtained oxidation products of arylthioglycolic acids with a free ortho position with sulfuric acid chlorohydrin, monohydrate, concentrated sulfuric acid, etc. (without or with the addition of agents which promote condensation) to vat dyes. These oxidation products of the arylthioglycolic acids have the constitution

R-SO-CH ₂ -COOH;

they are to be understood as sulfoxyacetic acids and, in the case of condensation, go with those mentioned above Agents directly into vat dyes of the thioindigo series. Depending on the selection of the aryl radical, the yields are different: Phenylsulfoxyacetic acid gives only very low yields, whereas substitution products are essential from case to case give better, sometimes very good yields, e.g. B. the halogen substitution products, such as p-chloro-δ-tolylsulfoxyacetic acid, p-dichlorosulf oxyacetic acid, ψ-cumylsulfoxyacetic acid etc. A condition for the formation of a vat dye is that an ortho position free is.

Example:

For the representation of p-chloro-o-tolylsulfoxyacetic acid

CTJ / / ^ TJ ι r * \

Λ S O CH ₂ - COO Η (ι)

44 g of the corresponding p-chloro-otolylthioglycolic acid are dissolved in about 25 g sodium hydroxide solution (40 ⁰ Be.) (just alkaline) and the necessary amount of water, nitrated and diluted with ice so that the temperature drops to 50 to ⁰ ° . At this temperature, the solution is mixed with 318 ecm of chlorine liquor, which contains 45 g of effective chlorine per liter, and left to stand for 12 to 24 hours. It is filtered and the filtrate is acidified with hydrochloric acid while cooling. After standing for a while, it is suctioned off and possibly recrystallized from hot water. White needles, soluble in hot water, cold fuel. Soluble in cold, concentrated sulfuric acid with a violet-blue color (the corresponding thioglycolic acid dissolves in it from yellow to brown).

Cl

Ήζ sr CH ₃

^x SO-CH ₉

Analysis: C ₆

COOH.

Found: Calculated:

C 46.83 percent 46.4 percent,

H 4.07 - 3.9 -

Cl 14.76 - 15.4 -

S 13.71-12.9

ι part of p-chloro-o-tolylsülfoxyessigsäure is now introduced into 2 parts by volume of chlorosulfonic acid with cooling, after the evolution of hydrochloric acid has ended is poured onto ice, suctioned off and washed with hot, dilute alkali, then with hot, diluted fuel. The dye obtained, which is identical to that obtainable from p-chloro-o-tolylthioglycolic acid is, stains cotton in the alkaline hydrosulfite vat with red-violet tones. If you apply ·. in the above example, 49 g instead of 44 g of p-chloro-o-tolylthioglycolic acid

55

60

70

m-chloroanisylthioglycolic acid or 40 g assym. rri-xylyl thioglycolic acid or 40.6 g of o-chlorophenylthioglycolic acid and if the rest of the procedure is as indicated above, the corresponding sulfoxyacetic acids are obtained. The same make white needles that are soluble in hot water, benzene, gasoline, wood spirit or glacial acetic acid Are the bodies in a similar way as given in the example above, with , Treated chlorosulfonic acid, one obtains from the m - chlorine - ο - anisyl and the assym. m-xylylsulfoxyacetic acid violet coloring vat dyes, from o-chlorophenylsulfoxyacetic acid a red coloring vat dye.

The same dyes as with chlorosulfonic acid are usually obtained in poorer yield also by means of concentrated sulfuric acid or monohydrate, etc. The condensation promoting agents, such as boric acid, exert a favorable influence on a case-by-case basis the yields.

Claims (1)

Patent claim: Process for the preparation of vat dyes, which consists in using arylsulfoxyacetic acids with a free ortho position with sulfuric acid chlorohydrin or concentrated sulfuric acid with or without Treated addition of the condensation promoting agents.