Synthesis of 1,4,5-trisubstituted-1,2,3-triazoles via coupling reaction of diaminomaleonitrile with aromatic diazonium salts

2,3-Diaminomaleonitrile: A Multifaceted Synthon in Organic Synthesis

2,3-Diaminomaleonitrile (DAMN), a tetramer of hydrogen cyanide, displays weakly basic properties and has reactivity comparable to o-phenylenediamine. It has emerged as a versatile, cheap as well as a readily accessible building block towards the synthesis of a variety of organic compounds. The present review focuses on the applications of 2,3-diaminomaleonitrile for the synthesis of Schiff's base, imidazoles, pyrazines, quinoxolines, benzodiazocines, 1,4-diazepines, purines, pyrimidines, pyrazine-tetrazole hybrids, triazoles, thiadiazole, thiazolidines, porphyrazines, formamidines, 1,3,5-triazepines, pyrrolo[3,4-b][1,4]diazepin-6(3H)-ones, triaza[22]annulenes, pyrrolo[3,4-f][1,3,5]triazepines, spiro compounds, pyrazoles and 2,3-dicyano-5,7-bismethylthieno[3,4-b]pyrazine.

N–H⋯O hydrogen bonding to the alkoxy oxygen of a carboxylic ester group: crystal structures of methyl 2,6-diaminobenzoate and its derivatives

Molecules with hydrogen bonds from amino groups to both oxygens of a carboxylic ester are described, and other examples of hydrogen bonding to an ester's alkoxy oxygen atom are highlighted.

Diaminomaleonitrile as a versatile building block for the synthesis of 4,4′-biimidazolidinylidenes and 4,4′-bithiazolidinylidenes

Ring closure reactions of diaminomaleonitrile (DAMN) with electrophilic aryl isocyanates and aryl isothiocyanates lead to the formation of the target 5,5′-diimino-1,1′-diaryl-4,4′-biimidazolidinylidene-2,2′-diones 2a,b and 2,2′-diarylimino-4,4′-bithiazolidinylidenes 4a–e, respectively. The protocol provides a new strategy for the synthesis of a wide range of alkenes with two electron-donating and two withdrawing substituents of DAMN in moderate to good yields.

Dimethyl Sulfoxide-Accelerated Reductive Deamination of Aromatic Amines with T-BuONO in Tetrahydrofuran

An efficient method for the conversion of aryl amines into arenes by a one-pot reductive deamination has been achieved. It was found the reductive deamination using t-BuONO in tetrahydrofuran could be accelerated by dimethyl sulfoxide and provided the deamination products with good yields under mild conditions. A plausible mechanism is discussed.

Energetic derivatives of 5-(5-amino-2H-1,2,3-triazol-4-yl)-1H-tetrazole

This study presents the preparation of the novel nitrogen-rich compound 5-(5-amino-2H-1,2,3-triazol-4-yl)-1H-tetrazole (5) in a five step synthesis, and additionally its more energetic derivatives with azido (6) and nitro (7) groups, as well as a diazene bridge (8).