DE236848C - - Google Patents

Description

The diaminodicarboxylic acid of the formula

COOH

has not yet been manufactured. It has now been achieved through acetylia and Oxidizing the corresponding diaminoxylene

ίο and saponifying the acetylated thus formed. Diaminodicarboxylic acid to produce this new acid. As the formula shows, this is what it is Acid in the closest relation to anthranilic acid. You could theoretically call it view double anthranilic acid.

It has now been found that this new acid is actually a valuable starting material for the production of dyes, pharmaceutical products and other valuable Carbon compounds can be used.

Example I.

Production of the 4 6-diacetaminobenzene

ι · 3 - dicarboxylic acids

. 209 parts of the hydrochloric acid salt of 4x6-diamino-ix3-xylene are mixed with 164 parts of molten sodium acetate and about 250 parts of acetic anhydride are added to this mixture. The reaction mixture is then boiled for one hour. After cooling, the mixture is dissolved in 1000 parts of warm water and the solution is boiled down to half its original volume. During the boiling and after cooling, the 4 * 6 'diacetamino-i · 3-xylene crystallizes out, which is filtered off, carefully washed with water and finally dried. Recrystallized from glacial acetic acid, the product is obtained in colorless needles which ^{melt at approximately 295 °} C. (corr.). . .

One part of this diacetaminoxylene and two parts of magnesium sulfate are made with 100 parts Water mixed. The mass is heated to boiling and to boiling liquid gradually added 3 parts of finely powdered potassium permanganate. After finished Oxidation, the hot solution is filtered and the filtrate is acidified with hydrochloric acid. As a result 5 " becomes the new 4 · 6-diacetaminobenzene-i · 3-dicarboxylic acid failed. This is filtered off, washed with water and dried. "

Example II.

Preparation of the 4 6-diaminobenzene

i · 3 - dicarboxylic acid.

To convert the diacetaminodicarboxylic acid into the diaminodicarboxylic acid, ι part of the diacetyl derivative suspended in 5 parts of concentrated hydrochloric acid and the Mixture heated to a boil. After about 10 to 15 minutes of cooking, a Obtained clear solution, from which almost immediately pale yellowish needles of the hydrochloric acid salt the diaminodicarboxylic acid crystallize out. Cooking then continues for 5 minutes. After cooling down, become. the crystals filtered off with concentrated hydrochloric acid washed and dried. If then 'ι part of this salt with 10 parts of water

Claims (1)

is added and then the liquid is made weakly alkaline with sodium hydroxide solution, a solution is obtained which, made acidic by acetic acid, contains the free 4 · 6-diamino-ι · 3-dicarboxylic acid (2 · 4-diamino-i-phthalic acid) precipitates. The precipitated powder is filtered off and can be further cleaned by redissolving it in dilute sodium hydroxide solution and again with acetic acid fails. The new dicarboxylic acid forms in pure The result is a colorless powder which gradually turns pink and ^{melts with decomposition at about 235 °} C. (corr.). The Di- IS acetyl compound is obtained after recrystallization from 95 percent alcohol in the form of long, colorless needles which melt at about 276 ° C. (corr.). The bisacetanthranil of the acid forms crystals which melt at about 283 ° C. (corr.). The condensation product of Bisacetanthranils with 2 moles. Aniline forms fine, colorless needles, melting which (corr.) At about 315 ⁰ C.. Godfather ν t- claim: Process for the preparation of 2 · 4-di- "amino-i-phthalic acid or its acidyl derivatives, consisting in that m-xylylenediamine is acidylated, then oxidized and possibly saponified.