Tin‐Catalyzed Synthesis of 5‐Substituted 1 H ‐Tetrazoles from Nitriles: Homogeneous and Heterogeneous Procedures

The preparation of 5‐substituted 1H‐tetrazoles was efficiently achieved by reaction of trimethylsilylazide with nitriles using a triorganotin alkoxide precatalyst. The reaction mechanism was first investigated using a homogeneous tributyltin derivative and was explored through experimental investigations and DFT calculations. A heterogeneous version was then developed using a polymer‐supported organotin alkoxide and afforded an efficient method for the preparation of tetrazoles in high yields with an easy work‐up and a residual tin concentration in the desired products compatible for pharmaceutical applications (less than 10 ppm).