2,6-Bis(tributyltin)benzo[1,2-b:5,4-b']dithiophene: a new synthon for organic semiconductors

A new tin-functionalized benzo[1,2-b:5,4-b'] dithiophene building block was synthesized that can provide access to a series of further extended pi-conjugated materials for Organic Field-Effect Transistors (OFETs) via Stille coupling protocol, as exemplified in two cases. The syn-configured benzodithiophene scaffold complements the well-established (anti) benzo[1,2-b:4,5-b'] dithiophene unit that has already been successfully employed in OFET devices. DFT-quantum theoretical calculations on a series of organic semiconductors support the selective modification of the band gap by either changing the HOMO, the LUMO, or both. The suitability of the tin-functionalized synthon to efficiently access a variety of organic semiconductor materials with different properties was also confirmed by the study of their photophysical features.