Synthesis and Study of Triazenes and 2-Iminoimidazolines Christopher W. Bielawski, Department of Chemistry & Biochemistry University of Texas at Austin, Austin, TX 78712 We discovered that N-heterocyclic carbenes react with organic azides to form 1,3-disubstituted triazenes; at elevated temperatures, 2-iminoimidazolines are formed: With an overarching goal of developing efficient synthetic routes to functional materials containing N-heterocycles, we have shown that the carbene / azide coupling reaction has tremendous promise in polymer synthesis (left) and in preparing substrates with useful electronic properties (right). UV-Vis absorption maxima were dependent on the complementarity of the triazene’s pendant donor and acceptor groups. Reflecting the high fidelity of the coupling reaction, azide-containing polymer molecular weight increased linearly with the quantity of N-heterocyclic carbene (NHC) added.