Tetrazole Compounds. 1. 1‐Aryl‐5‐(2‐dialkylamino‐vinyl)‐1H‐tetrazoles from 3‐Chloropropeniminium Salts
3‐Chloropropeniminium salts 1 react with excess sodium azide in refluxing alcohols to give mainly 1‐aryl‐5‐(2‐dialkylamino‐vinyl)‐1H‐tetrazoles 3; in minor quantities isomeric 5‐aryl‐1‐(2‐dialkylamino‐vinyl)‐1H‐tetrazoles 4 are formed. The reaction involves splitting off N2 and C → N migration of the aryl and dialkylaminovinyl group, respectively. A cross‐over experiment indicated that the rearrangement step proceeds intramolecularly. — The i.r., u.v., and n.m.r. spectroscopic data of the novel 1H‐tetrazoles 3 as well as the u.v. spectra of some new starting products 1k—v are reported.