Meta-B-entacenes: new polycyclic aromatics incorporating two fused borepin rings

The synthesis of new boron-containing acenes (meta-B-entacenes) is reported. These compounds exhibit slightly non-planar core geometries with blue-shifted spectral properties and more negative electrochemical reduction potentials relative to known para isomers. Polarizable pi-extended architectures were realized via cross-coupling procedures with chloro-functionalized precursors.