FSO 2 N 3 -Enabled Synthesis of Tetrazoles from Amidines and Guanidines.

Herein we report the facile syntheses of tetrazoles enabled by FSO 2 N 3 under mild conditions. FSO 2 N 3 has been shown as the most powerful diazotizing reagent, which converts thousands of primary amines to azides fast and orthogonally. As the follow-up studies of the diazo transfer reaction using FSO 2 N 3 , we discover that amidines and guanidines are rapidly transformed into tetrazole derivatives when reacting with FSO 2 N 3 under an aqueous environment, which is unprecedented for tetrazole synthesis.