Diaminomaleonitrile reagent

Methods of imidazole synthesis based on the use of diaminomaleonitrile (DAMN (13), R = II) have proliferated in recent years. The reagent is now readily available from chemical distributors at a price which makes its use reasonably economical. Some of these methods of synthesis fall under the present heading others involve 1,5 bond formation (see Section 2.2), or 1,2 and 2,3 bond formation (see Section 3.1.1). 

Bredereck and Schmotzer (1044), from diaminomaleonitrile (DAMN hydrogen cyanide tetramer) and oxalyl chloride, prepared 2,3-dicyano-5,6-dihydroxy-pyrazine but Stetten and Fox (1049) could not prepare 23-diamino-5-hydroxy-pyrazine from glycine amide and oxamide. Section 11.3 lists preparations from a, -diamino or a, -diimino compounds and reagents other than a,0-dicarbonyl compounds (384) with additional data (1050) and oxidation of 23-dichloro-quinoxaline with hot aqueous potassium permanganate gave 23-dicarboxy-5,6-dihydroxypyrazine (1051). 

Cyanoimidazoles as a class are synthesized conveniently from diaminomaleonitrile (DAMN, 1)—a tetramer of hydrogen cyanide—and electrophilic carbon reagents. Reaction of DAMN with cyanogen chloride affords 2-amino-4,5-dicyanoimidazole (2) in moderate yield [1]. 

Given that tetrachlorocyclohexanedione 539 (Guirado et al. 1997) can be used as a synthetic equivalent of unavailable 3,6-dichloro-l,2-benzoquinone, it was reacted with diaminomaleonitrile 468 to provide successfiiUy, 5,8-dichloro-2,3-dicyanoquinoxaline 540 in quantitative yield (Scheme 2.129) (Guirado et al. 2011). On exploring the reactions between nucleophilic reagents and the latter, a... 

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