Synthesis of Octabromoperylene Dianhydride and Diimides: Evidence of Halogen Bonding and Semiconducting Properties.

A facile synthesis of octabromoperylene-3,4,9,10-tetracarboxylic dianhydride (Br8-PDA) (1), its diimides (Br8-PDIs) (2a-e), and bis-, tris-, and tetra-amino substituted diimides (5a-c) with six, five, and four remaining substitutable Br atoms, respectively, is reported. Octabromination results in facile chemical/electrochemical reduction, radical anion formation, and red-shifted optical properties. For the first time, diverse halogen-bonding interactions were identified in the PDA/PDI, which along with the attractive electronic features enhance the electron-transport characteristics compared to the di-/tetra-brominated PDIs (3/4).

BODIPY-thiophene copolymers as p-channel semiconductors for organic thin-film transistors.

The synthesis and physicochemical properties of a new class of BODIPY-based donor-acceptor π-conjugated polymers are presented. Solution-processed top-gate/bottom-contact (TG-BC) thin-film transistors on flexible plastic substrates exhibit air-stable p-channel activities with charge carrier mobilities as high as 0.17 cm(2) /V·s and current on/off ratios of 10(5) -10(6) , the highest reported to date for a BODIPY-based semiconductor. The results shown here indicate a significant charge-transport improvement (>10000×) in BODIPY-based polymeric semiconductors, demonstrating its potential in future organic optoelectronic applications.