Exploration of Syntheses and Functions of Higher Ladder-type pi-Conjugated Heteroacenes

Ladder-type heteroacenes with well-defined structures and highly planar and delocalized pi-electrons are an important class of materials for potential applications in organic electronics. The incorporation of heteroatoms into the ladder backbone allows for tuning optical-electronic properties and crystal structures in the solid state. Significant progress in synthesis and physical studies of a number of fascinating ladder molecules has been achieved. This review discusses progression in synthetic methods, structural characterization, and applications of ladder-type heteroacenes.