With support from the Organic Dynamics Program, Dr. Rudolph A. Abramovitch will study the synthesis and chemistry of five-membered heterocyclic nitrenium ions. These species are highly reactive intermediates whose chemical reactivity is of interest to physical organic chemists and to theoretical chemists. In addition to their inherent theoretical interest, these species are of potential importance as a new class of electrophilic primary aminating agents that are of interest to synthetic organic chemists as well. Of particular interest is the potential ability of these species to undergo isomerization to other cationic systems. The generation and trapping of these heterocyclic sigma-cations by nucleophiles will be studied via ion cyclotron resonance mass spectrometry in an effort to obtain information concerning the operation of pi-to-sigma "electronic isomerizations" in the nitrenium ions. Trapping experiments will also be performed in solution with the same objective in mind. Detailed analysis of the various reaction products thereby obtained is expected to afford insight into the nature of the reactive intermediate(s) present in each case.
