A practical multigram-scale method for the green synthesis of 5-substituted-1H-tetrazoles in deep eutectic solvent.

Graphical abstract Highlights • Practical one-pot reaction for preparation of 5-substituted-1 H -tetrazoles. • Without using high boiling point or volatile organic solvents in the reaction. • Easy reaction set-up and multigram scale. Abstract A series of 5-substituted-1 H -tetrazoles have been efficiently synthesized in moderate to excellent yields (68–90%) under mild reaction conditions by combining aryl aldehydes, hydroxylamine hydrochloride with sodium azide in the presence of catalytic amount of Cu(OAc) 2 in deep eutectic solvent (DES). The new synthetic method has many advantages, such as high conversion, green reaction medium, easy work-up, low cost, and environment friendly. [ABSTRACT FROM AUTHOR]