Abstract Tetrazoles are prepared in good yields from alkyl and aryl nitriles by treatment with equimolar trimethylaluminum and trimethylsilylazide. Yields, substrate compatibility, and reaction temperature are comparable with the use of other metal azides such as Al (N 3) 3 and n-Bu 3 SnN 3. The reactions are run in toluene or with added THF at 80 C.