Straightforward access to fluoroalkyl tetrazoles from fluoroalkyl N-sulfonylhydrazones

Herein we reported a metal-free cycloaddition reaction of fluoroalkyl N-sulfonylhydrazones with arene-diazonium salts to form the corresponding fluoroalkylated tetrazole products. This transformation represents the first general and operationally safe procedure to access mono-, di- and perfluoroalkyl tetrazole products. A total of 77 previously inaccessible fluoroalkyl tetrazoles were reported in good-to-excellent yields, with excellent tolerance of diverse functional groups. Moreover, monofluoroalkyl N-triftosylhydrazone (MFHZ-Tfs) was synthesised for the first time, and was applied as a mono-fluoromethyldiazo reagent.

Automated summary

A metal-free cycloaddition reaction of fluoroalkyl N-sulfonylhydrazones with arene-diazonium salts to form fluoroalkylated tetrazole products was reported. This procedure provides a general and safe method for accessing mono-, di-, and perfluoroalkyl tetrazoles with excellent yields and tolerance of diverse functional groups.