Bis‐isoindigos: New Electron‐Deficient Building Blocks for Constructing Conjugated Polymers with Extended Electron Delocalization

Incorporation of acceptor-acceptor (A-A) type moieties into donor-acceptor (D-A) type conjugated polymers becomes a new strategy to tune their electronic properties. In this work, we first demonstrate an efficient convergent route to prepare isoindigo-based A-A type building blocks - bis-isoindigos - via the palladium-catalyzed oxidative coupling. Bis-isoindigo-based polymers show high planarity and delocalized frontier molecular orbitals with...