Synthesis of new bis 1-substituted 5H-tetrazoles via efficient heterocyclizations from symmetric dianilines, methyl orthoester and sodium azide

Then, we herein describe the synthesis and characterization of three new bis 1-substituted-5H-tetrazoles. Two were synthesized in a single step via a heterocyclization involving primary amines, an orthoester and sodium azide in 30 to 91% yield. Besides, one was prepared via a three-step-based synthetic methodology: S_NAr (32%), nitro group reduction (66%) and primary amine heterocyclization (83%) for an overall yield of 18%. It is noteworthy that those ligands neither have been synthesized nor isolated before. The aim of these syntheses is the use of new tetrazole-based ligands for the construction of novel MOF structures to evaluate their gas capture properties, such as CO₂ under relative humidity conditions.