Indenoindenodi(benzothiophene)s (IIDBT)

Case ID:
Web Published:

University of Oregon researchers have developed novel indenofluorene and diindenothiophene molecules ideal for OLED, semiconductor, or solar applications

Polyaromatic hydrocarbon compounds, such as pentacene, are a class of compounds that have been explored as conducting organic materials for use in device applications, such as organic light-emitting diodes (OLEDs), field-effect transistors (OFETs), and solar cells. However, such materials are difficult to make and pentacene, in particular, readily oxidizes to its respective quinone in aerobic conditions and reacts with itself to afford a butterfly dimer. The driving force for both reactions is the formation of two aromatic naphthalene units, which ultimately disrupts overall conjugation and thus leads to poor device performance. While degradation can be slowed in such compounds, these processes are not completely suppressed. As such, efficient electron transfer can be disrupted. There exists a need in the art for different organic compounds that can be used in various electronic and electrooptical devices.

Our scientists have created novel indenofluorene (IF) molecules that are excellent alternatives to degradation-prone pentacenes for organic light emitting diode (OLED), organic field-effect transistor (OFET) and semiconductor research and applications. Compared to pentacene and fullerene, indenofluorenes offer more efficient electron transfer. Unlike pentacenes, which can degrade quickly and significantly when exposed to light and air, some indenofluorenes have been exposed to light for more than three months without significant degradation.

Our scientists were the first to synthesize fully conjugated indenofluorenes; they have produced a variety of fully conjugated IF derivatives and have shown that IFs can be prepared in 10 gram quantities with good yields and excellent purity using methods that are can be adapted to large-scale production. Unlike other solutions which are silicon-based, indenofluorenes work when laid on plastics and other materials, which means products developed with IFs can be flexible, stretchable and bendable. This paves the way for a whole new type of foldable or rollable screen, and other novel devices and applications.

This lab is also developing and synthesizing new Diindenothiophene molecules, which have fantastic properties for organic semiconductor development, research and applications.


  • Unlike pentacenes, indenofluorenes are non-emissive
  • Starting materials are cheap and plentiful
  • Can be produced in 10 gram quantities
  • Indenofluorenes possess absorption levels and HOMO-LUMO energy levels and gaps similar to pentacenes
  • Indenofluorenes are stable and anti-aromatic
  • Unlike pentacenes, indenofluorenes do not readily degrade
  • Excellent semiconducting polymers for high performance, air-stable transistors
  • Somewhat uniquely, indenofluorenes move both positive and negative charges
  • Low driving voltages


  • OLED research and development
  • Thin film transistor research and development
  • Optical research and development
  • Electronic device research and development
  • Solar and photovoltaic research and development
  • OFET research and development
  • Semiconductor research and development

US Patents # 11,021,489,  9,773,988,  8,921,578

Patent Information:
For Information, Contact:
Christine Gramer
Senior Technology Development Associate
University of Oregon
Michael Haley
Justin Dressler
Joshua Barker
© 2024. All Rights Reserved. Powered by Inteum