Benzo[1,2-b:6,5-b′]dithiophene(dithiazole)-4,5-dione derivatives: Synthesis, electronic properties, crystal packing and charge transport

Yulia A. Getmanenko, Marina Fonari, Chad Risko, Bhupinder Sandhu, Elena Galán, Lingyun Zhu, Paul Tongwa, Do Kyung Hwang, Sanjeev Singh, He Wang, Shree Prakash Tiwari, Yueh Lin Loo, Jean Luc Brédas, Bernard Kippelen, Tatiana Timofeeva, Seth R. Marder*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

22 Scopus citations


A series of dihalo- and bis-aroyl-substituted benzo[1,2-b:6,5-b′] dithiophene-4,5-diones were synthesized, and their electronic, electrochemical, and electrical properties investigated. Synthetic strategies to increase (i) the conjugation length of the base molecular structure-through introduction of thiophene units bearing electronically neutral substituents (hydrogen or alkyl groups) or strong electron-withdrawing pentafluorobenzoyl group(s)-and (ii) the electron affinity-by moving to a benzo[1,2-d:4,3-d′]bis(thiazole)-4,5- dione structure-were developed. Molecular packing in the single crystal was studied by single-crystal X-ray structural analysis, and this information was subsequently used in the determination of the electronic band structures, densities of states (DOS), effective transfer integrals, and effective charge-carrier masses via density functional theory (DFT) methods. The charge-carrier transport properties of the benzo[1,2-b:6,5-b′]dithiophene- 4,5-dione and benzo[1,2-d:4,3-d′]bis(thiazole)-4,5-dione derivatives were investigated through the fabrication and characterization of organic field-effect transistors (OFETs) via both solution-processed and vacuum-deposited films. 2,7-Bis-pentafluorobenzoyl-benzo[1,2-b:6,5-b′] dithiophene-4,5-dione (10a) exhibited field-effect behavior with an average electron mobility μe = 4.4 (±1.7) × 10-4 cm2 V-1 s-1 when the active layer was vacuum-deposited, and a larger μe= 6.9 × 10-3 cm2 V-1 s-1 when the active layer was solution-processed. These results are in stark contrast with the DFT-determined electronic band structure and effective mass, which indicate that the material possesses good intrinsic charge-carrier transport characteristics. The combined results reveal the importance of thin-film processing and that further processing refinements could lead to improved device performance. Only one material with benzo[1,2-d:4,3-d′]bis(thiazole)-4,5-dione core, 2,7-bis-(4-n-hexyl-thiophene-2-yl)-benzo[1,2-d:4,3-d′]bis(thiazole)-4, 5-dione (19d), showed average μe = 8.2 × 10-5 cm2 V-1 s-1 in OFET with solution-processed active layer. Unexpectedly, measurable hole transport was observed for 2,7-bis-(5-n-nonyl-thiophen-2-yl)-benzo[1,2-b:6,5-b′]dithiophene-4, 5-dione (19b) (μh = 8.5 × 10-5 cm2 V-1 s-1) and 2,6-bis-(thiophen-2-yl)-3,5-di-n-hexyl-4H- cyclopenta[1,2-b:5,4-b′]dithiophen-4-one (30a) (μh = 3.7 × 10-4 cm2 V-1 s-1).

Original languageEnglish (US)
Pages (from-to)1467-1481
Number of pages15
Issue number7
StatePublished - Feb 21 2013
Externally publishedYes

ASJC Scopus subject areas

  • General Chemistry
  • Materials Chemistry


Dive into the research topics of 'Benzo[1,2-b:6,5-b′]dithiophene(dithiazole)-4,5-dione derivatives: Synthesis, electronic properties, crystal packing and charge transport'. Together they form a unique fingerprint.

Cite this