the invention is a process for preparing 1 , 4 - diazoniabicycloalkanes of formula i wherein the corresponding 1 - hydro - 4 - aza - 1 - azoniabi - cycloalkane salt of the 1 , 4 - diazabicycloalkane is fluorinated in the presence of an alkali metal salt under reaction conditions sufficient to form the desired 1 , 4 - diazoniabicycloalkane . ## str1 ## wherein n represents 0 , 1 or 2 ; each r 1 , r 2 , r 3 , r 4 and r 5 independently represents hydrogen , c 1 - c 6 alkyl , aryl , c 1 - c 6 alkyl - substituted aryl or aryl - substituted c 1 - c 6 alkyl ; and each x - represents a counterion or 2x - represents a single divalent counterion .