1. Development and Applications of a New Triazene Forming Reaction
Christopher W. Bielawski, Department of Chemistry & Biochemistry
University of Texas at Austin, Austin, TX 78712
UV-Vis absorption maxima were dependent on the complementarity of the respective triazene’s pendant donor and acceptor groups (structures above are color coded with spectra shown to the left).
N-heterocyclic carbenes were found to react quantitatively with a range of organic azides to form 1,3-disubstituted triazenes. This novel reactivity enabled the development of: (1) new classes of donor-acceptor organic molecules (upper right), (2) a new method for precisely modifying azide containing polymers (lower left), and (3) the realization of a new class of highly processible, conjugated polymers that can be rendered conductive (lower right).
Combining a bis(NHC) with a bis(azide) afforded a new class of highly soluble polytriazenes (top). Thin films of these polymers (bottom) were found to be electrically-conductive ( = 10-3 S/cm) upon doping with iodine.
Reflecting the high fidelity of the coupling reaction, azide-containing polymer molecular weight increased linearly with the quantity of N-heterocyclic carbene added.