B04 • B,E-Doped Acene- and Rylene-Based PAHs, Dyads, and Ladder Polymers
The replacement of selected sp2-hybridized C atoms in p-conjugated organic compounds, especially polycyclic aromatic hydrocarbons (PAHs), with B and E atoms (E = N, O, or S) frequently furnishes heteroatom-doped hybrid compounds with enhanced optoelectronic properties compared to those of their carbonaceous counterparts. Moreover, the symmetry breaking induced by B,E-incorporation can significantly improve the selectivity in late-stage derivatizations.
Our laboratories have developed several efficient synthesis strategies for a broad variety of B,E-PAHs and polymers, including: (I) cyclization reactions via Au(I)-catalyzed addition of BO‒H or BN‒H bonds from borinic acids or aminoboranes, respectively, across strategically positioned alkynyl substituents, (II) targeted hydrolysis or aminolysis of arylene-bridged diborane(6) derivatives, (III) ring-expansion reactions of strained boron-containing heterocycles, (IV) nucleophilic aromatic substitution (SNAr) reactions on C-fluorinated B-doped PAHs, (V) (catalytic) silicon/boron exchange (poly)condensation reactions, and (VI) anionic cyclodehydrogenation processes.
This toolbox will be further extended and applied to the synthesis of acene- and rylene-based PAHs, donor‒acceptor dyads, and (macro)molecular materials with a special focus on applications as narrow-band emitters, strong electron acceptors, and smallmolecule sensors.
