DE2559520C3 - Ethylene-l ^ -bis-phenyM ^ '- carboxylic acid-bis-N-chloramide and naphthalene-2,6-dicarboxylic acid-bis-N-chloramide and processes for their preparation - Google Patents

Description

Bis-N-chloramides are valuable intermediate compounds that are used, among other things, for the production of diurethanes, Diureas, diamines and diisocyanates can be used. From DT-PS 9 09 455 and one Publication by Eckert et al. in Reyon + Synthetica + Viscose wool 29, pages 43-5J (1951) are the only aliphatic representatives of this class of substances Adipic, pimeline, cork and sebacic acid-bis-N-chlorainide known. These compounds can be reduced to 37 to 95% strength according to the seduction described there Establish yield. On the other hand, there has not yet been any for the production of aromatic bis-N-chloramides suitable method known. Only in US-PS Jl 05 848 is the production of isophthalic acid-bis-N-chloramide described by chlorinating isophthalic acid camide. When reworking this well-known The process gives isophthalic acid-bis-N-chloramide but in a yield of only 3.5% of theory. Th. The isomeric terephihalic acid-bis-N-chloramide! Ate do not manufacture by this process at all.

Most recently it succeeded after one in the BE-PS 8 12 357, both terephthalic acid and also synthesize isophthalic acid-bis-N-chloramide in high yield / u. Further aromatic bis-N-chloramides have not yet become known.

Because of the importance of bis-N-chloramides as precursors of technically important diisocyanates, there was a need to create more connections in this class of sloffs.

The present invention relates to ethylene-l ^ -bis-phenyl ^ / l'-dicarboxylic acid-bis-N-chloramide and naphtha lin-1, b-dicarboxylic acid-bis-N-chloramide and the process for the preparation of these compounds, which is characterized in that Äthylen-1,2-bis-pheny I-4,4'diearbonsäurea mid or naphthalene-l.ö-dicarbonsäurediamid in a mixture of glacial acetic acid and an alkali acetate, preferably sodium acetate, at temperatures of 10 to 30 ⁰ C chlorinated.

The chlorination of the acid amides is exothermic. The process according to the invention is carried out at temperatures carried out from 10 to 30 "C. The use of higher temperatures is disadvantageous insofar as below Under these conditions, considerable amounts of the corresponding dicarboxylic acid are produced by hydrolysis. the end For economic reasons, the chlorination is preferably carried out at 5 to 25 ° C, with the heat of reaction can be removed by water cooling.

The process according to the invention can be carried out either under normal pressure or under increased pressure will. With increasing pressure, the required reaction time decreases, the preferred pressure range however, for economic reasons it is between 1 and 6 ata.

Since the chlorination takes place in the heterogeneous phase in the process according to the invention, it is good Ensure mixing of the suspension. The dilution of the reaction mixture should be at least so be measured so that the same can be stirred or otherwise mixed without difficulty can.

If the process conditions mentioned are observed, the chlorination is complete after about 0.25 to 2 hours. The amide is practically quantitatively converted into the bis-N-chloramide without a solution in the meantime. The suspension present after the chlorination is complete contains only the N-chloramide as a solid. The products can be used in the simplest manner, for. B. by filtering off or spinning off. After washing z. B. with cold water and drying at z. B. 50 ⁰ C in a vacuum you get them in the highest purity.

The substances do not have sharp melting points. They split from about 100 ° C gradually chlorine and show from about 200 ⁰ C significantly discolored.

As already mentioned, the substances according to the invention can be technically more important for the production Diisocyanates are used. An example of this is the procedure of DT-AS 25 02 428, according to which the Bis-N-chloramides are first converted to bis-sulfonylureas, their subsequent fragmentation leads to the corresponding diisocyanates. The bis-N-chloramides according to the invention are used as starting materials for the synthesis of bis-sulfonylureas the starting materials previously used for this purpose think:

Bis-sulfonylureas, whose urea groups are replaced by an aliphatic or a cycloaliphatic radical are connected to each other, according to the information of US-PS 29 62 530 by reaction of a sulfonyl isocyanate, a sulfonylcarbamic acid chloride, carbamic acid ester, urea, acylurea or one substituted nitrourea can be obtained with a diamine. Furthermore, from the above USA patent known bis-sulfonylureas from a sulfonic acid amide and a diisocyanate or a correspondingly reactive compound, such as. B. a urea, nitrourea, bis-carbamic acid ester, Bis-carboxamide or bis-carboxamide-Ν, Ν'-halide, to synthesize. Furthermore, there is still the possibility of the synthesis from a Sulfonic acid chloride and a bis-isourea alkyl ether pointed out. So far, however, only one has been used for the technical synthesis of bis-sulfonic ureas Synthesis from sulfonyl diisocyanate and sulfonic acid amide into consideration, the other syntheses because of their low selectivity or, because of the poor accessibility of the starting materials, no input in found the technology. However, sulfonylureas are relatively expensive compounds. In contrast, the Bis-N-chloramides according to the invention are compounds that are more readily available and simple can be further processed into technical diisocyanates.

example 1

17 g (= 63.5 mmol) of ethylene-1,2-bis-phenyl-4,4'-carboxamide were in a solution of 500 ml of glacial acetic acid and 10.4 g (0.127 mol) of nairium acetate vigorous stirring. After six hours of chlorination, the slurry became yellow suctioned off and washed twice with 30 ml of glacial acetic acid each and then twice with 50 ml of water each time. A total of 18.5 g (= 86% of the theory)

Ethylene-l ^ -bis-phenyM ^ '-carboxylic acid-bis-N-chloramide can be isolated as a colorless, fine-grained powder.

Ben: C 56.98, H 4.18, N 8.31, Cl 21.03;
Found: C 57.5, H 4.0, N 8.1, Cl 21.5.

IR stretching oscillation C = O
NH

1640-1645 cm- ',
3150-3130Cm- ¹ .

Example 2

21.4 g (0.1 mole) of 2,6-naphthalenedicarboxylic acid diamide were analogous to Example 1 in a solution of 500 ml of glacial acetic acid and 18 g (0.22 mol) of sodium acetate entered vigorous stirring. In the well-stirred suspension was in the course of 5 hours at A finely divided stream of chlorine was initiated at room temperature. When the reaction was over, it became white The precipitate is filtered off with suction through a glass frit and washed three times with 20 ml of cold water each time. To left after drying 28.1 g (= 99% of theory) of naphthalene ^ i-dicarboxylic acid-bis-N-chloramide as a fine, colorless powder.

Ben: C 50.90, H 2.85, N 9.90, Cl 25.05;
Found: C 51.5, 112.6, N 10.4. Cl 24.2.

IR stretching oscillation C = O 1640-1650cm '.
NH 3120-100 cm ■ '.

Claims (2)

Patent claims: 1. Ethylene-l ^ -bis-phenyl-M'-dicarboxylic acid-bis-N-chloramide and naphthalene-1,6-dicarboxylic acid-bis-N-chloramide. 2. Process for the preparation of the compounds according to claim 1, characterized in that ethylene-1 ^ -bis-phenyl - ^ '- dicarboxylic acid diamide or naphthalene-1,6-dicarboxylic acid diamide in a mixture of glacial acetic acid and an alkali acetate at temperatures of 10 Chlorinated up to JO ^{0 C.} J. The method according to claim 2, characterized in that that sodium acetate is used as the alkali acetate.