Lewis Acid Mediated Tandem Reaction of Propargylic Alcohols to Tetrazoles Involving C—O‐ and C—C‐Bond Cleavage Reactions and a C—N‐Bond Formation.

A novel and direct synthesis of 1-aryl-5-arylvinyltetrazoles from easily prepared propargylic alcohols and TMSN3 is developed in the presence of TMSCl under mild conditions (TMS=trimethylsilyl). The process involves an allenylazide intermediate, followed by a C-C-bond cleavage and C-N-bond formation to afford the desired products. Moreover, this method offers a good functional-group applicability and can be scaled-up to grams (yield up to 85 %).