Dithieno[2,3-d;2′,3′-d]benzo[2,1-b;3,4-b‘]dithiophene: a novel building-block for a planar copolymer

A planar heteroacene building block, dithieno[2,3-d;2′,3′-d′]benzo[1,2-b;3,4-b′]dithiophene (DTmBDT), is reported via a facile synthetic procedure. Single-crystal X-ray diffraction of Br₂-DTmBDT reveals that dodecyl chains interdigitate, still enabling close π-stacking of 3.42 Å. A very high molecular weight quasi-planar copolymer PDTmBDT-DPP exhibited a high hole mobility of 0.36 cm² V⁻¹ s⁻¹ in preliminary studies of organic field-effect transistors.