The first synthesis of alkyl disulfonimide oligomers is presented. In the process of synthesizing these oligomers, previously unreported reactivity of the N-substituted disulfonimide functional group was discovered. Under basic conditions, unexpected lengthening of the oligomers occurs through a "transdisulfonimidation" reaction, whereby new disulfonimides are synthesized from existing ones by reaction with sulfonamide anion. This process appears to proceed via formation of a sulfene intermediate. Support for the ElcB(Rev) mechanism includes isotope scrambling, substituent effects, and sulfene trapping.