The reaction of 2-alkylideneadamantanes with nitrosyl chloride afforded the corresponding dimeric 1,2-bis[1-(2-chloroadamantan-2-yl)alkyl]diazene 1,2-dioxides, while monomeric α-chloro oximes were obtained from 2-(chloromethylidene)adamantane and 2-benzylideneadamantane.