Organocatalyzed Green Synthesis of 2,3-dihydropyrazines en Route to Medicinally Privileged Novel Polyheterocyclic Systems

A straightforward green synthesis of 2,3-dihydropyrazines was accomplished under the catalytic influence of (±)-Camphor-10-sulfonic acid at room temperature by condensation of aliphatic 1,2-diamines with αβ-dicarbonyl compounds in aqueous medium. Remarkable aspects of this newly reported method are high yields, use of non-toxic solvents, mild conditions, simple workup and synthesis of complex molecules using an ecofriendly inexpensive organocatalyst. The present method is atom-economical, environmentally benign, and affords synthetically useful and challenging products very rapidly.