Sila-annulated terrylene diimides for balanced ambipolar transporting

The key building blocks,tetrachlorinated terrylene diimides and the targeted sila-annulated terrylene diimides(Si-TDIs and 2Si-TDIs)were synthesized for the first time.Single-crystal analysis verified the almost planar molecular configurations of both Si-TDIs and 2Si-TDIs.They exhibited intriguing optical properties including red-shifted absorption and near-infrared emission properties with excellent fluorescence quantum yields,as well as precisely controlled HOMO/LUMO energy levels by Si-heteroannulation.The single-crystal organic field-effect transistors based on 2Si-TDI 5a featuring long and branched alkyl chains demonstrated well-balanced ambipolar transporting properties with electron/hole mobilities of 0.10/0.18 cm2 V^(−1)s^(−1).