Synthesis of new triazolo[1,5-a]pyrimidine using ketene dithioacetals

Triazole and its derivatives as highly significant nitrogen-containing heterocycles are attracted considerable attention in fields, such as medicinal and agrochemical research as well as in the material sciences due to their unique structure, hydrogen-bonding and dipole interactions.1 Many substituted triazole compounds continue to be of scientific and engineering interest. The scaffolds containing triazole are promising candidates to inhibit acidic corrosion of steel. The interesting biological activities of triazole are versatile such as anticancer, anti-human immunodeficiency virus, antilieshmanial, antitrypanosomal, and antibiotic.2 In the view of above-mentioned points, an interesting one-pot four-component reaction developed for the synthesis of N-methyl-6-nitro-5-phenyl-[1,2,4]triazolo[1,5-a]pyrimidine-7-amine 5 via reaction of primary aliphatic or aromatic amines 1, nitroketene dithioacetals 2 followed by the subsequent condensation with aliphatic or aromatic aldehydes 3 and 3-amino-1,2,4-triazole 4 in the presence of trichloroacetic acid (TCAA) as a Brønsted-Lowry acidic catalyst (Scheme 1). The direction of heterocyclization and the structure of final products identified spectroscopically.

Keywords:

3-Amino-1 , 2 , 4-triazole , Nitroketene dithioacetals , Triazolo pyrimidine , Multicomponent reactions.