Stabilization by Benzannulation: Butterfly Azaacenes

Abstract

Soluble butterfly-shaped tetraazapentacenes and tetraazaheptacenes were prepared by condensation or Stille coupling with a stannafluorene. The stability of the benzo-winged tetraazaheptacene is dramatically increased through the fourfold benzannulation, yet its acene character is retained to a significant extent.

Keywords: X-ray diffraction; benzannulation; condensation; heptacenes; heteroacenes.