Maleic acid diamide

Maleamide Maleic acid diamide, malein-amide)... 

The reaction partner of maleic acid anhydride can be changed. Instead of a hydroxyl group a primary or secondary amine can be used. Either monoamides or diamides can be obtained. Simple sulfation as mentioned above closes the reaction series. The variety of sulfosuccinamates (monoamides) and sulfosuccinamides (diamides) is smaller than that of sulfosuccinates. An important use lies in the field of technical applications (Fig. 2). 

Compound 38 is obtained, for example, by condensing 2-amino-4-methylphe-nol with maleic acid to yield the diamide. Ring closure and the formation of the ethylene bridge occur on heating in a mixture of diphenyl ether and diphenyl at 135-155 °C in the presence of boric acid [68],... 

Oxonium salts alkylate diamides of dicarboxylic acids twice, provided the amide groups are separated by at least two carbon atoms,thus the bis(dimethylamides) of maleic acid or terephthalic acid have been converted to dications (69 Scheme 4) by means of oxonium salts. ... 

For the synthesis of sulfosuccinamates, maleic anhydride is reacted with the particular amine needed to give the required maleic acid monoamide, which can then be transformed to the sulfosuccinamate by sulfonation with sodium bisulfate in aqueous solution. The preparation of diamides is similar to that used for preparing diesters. 

Amidation. Reaction of maleic anhydride or its isomeric acids with ammonia [7664-41-7] (qv), primary amines (qv), and secondary amines produces mono- or diamides. The monoamide derivative from the reaction of ammonia and maleic anhydride is called maleamic acid [557-24-4] (8). Another monoamide derivative formed from the reaction of aniline [62-53-3] and maleic anhydride is maleanilic acid [555-59-9] (9). 

Maleic hydrazide (149), produced on a large scale as a herbicide, can be obtained, according to a patent, from a simple diaziridine, which on an industrial scale could be less expensive than hydrazine hydrate. In the proposed manufacture of diamide (150) from a diaziridine and urea it must be taken into account that the reaction of urea is preceded by solvolytic hydrazine formation, which probably proceeds under the reported conditions (several hours, 70-80 °C, acidic media) (79AHC(24)63). 

An alternative mechanism may include first an O-inserhon step, followed by the transformation of the oxidized compound into the cyano-containing compound. An example might be the oxidation of butadiene to maleic anhydride followed by hydrolysis to the acid, the formation of the diamide and the oxydehydrogenation to the dinitrile. 

Recently, thiocarboxylic acids and their salts have been reported by Tokashima etal to add to MA. Thus, 2-iminocyclopentanedithiocarboxylic acid 35a and 2-cyclohexyliminocyclopentanedithiocarboxylic acid 35b gave 75% and 83% yields, respectively, of the adducts 36. Maleimide, maleic diamide, and esters were all shown to undergo the reaction under very mild conditions. 

MA Diels-Alder reactions, 130 MA-epoxide reaction, 508 maleimide-amide reaction catalysts, 512 MA polymerization initiators, 256 2-Iminocyclopentanedithiocarboxylic acid MA reaction, 51 maleic diamide adduct, 51 maleimide adduct, 51... 

Related to the sulfosuccinic diesters are the sulfosuccinamides, succinimides, and succinamates, which may show some advantage in stability but usually require more harsh conditions for formation. The sulfosuccinic diamide materials are prepared in a manner similar to that for the diesters from maleic anhydride or the free acid and a primary or secondary amine, followed by the addition of sodium bisulfite across the double bond to give materials of the general structure... 

---