Double Helical OligoTolans: Models for soluble OLED Polymers

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Double Helical Oligo-TolansModels for soluble
OLED Polymers

• Florian KrausJay S. Siegel

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2
1 University of Regensburg, Germany
2 University of California, San Diego
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Conducting Polymers

• Can provide electromagnetic shielding of
  electronic circuits
• Can be used as antistatic coating material to
  prevent electrical discharge exposure on
  photographic emulsions
• Can be used as hole injecting electrodes for
  OLEDS
• Usage in electroluminescent displays (mobile
  telephones)
• In use as emissive layer in full-color video
  matrix displays
• Some are promising for field-effect transistors
  (Usage in supermarket checkouts)
• Some absorb microwaves stealth technique

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OLEDs
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OLEDs - when electrons and holes meet
Jablonski Diagram
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OLEDs
The principle Through the recombination of holes
and electrons energy is gained and emitted as
visible light. Advantages over liquid
crystals Large surfaces can be covered in
unlimited visual angles.
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Non-linear Optics
What it is and why we need it

• The refractive index of an NLO-material can be
  changed drastically by light of high intensity
  (LASER), making it a high speed switch and also a
  high density optical data storage medium.
• Information storage and transmission goes away
  from the electrical to the optical regime.
  NLO-materials can be cast in any shape, circuits
  can be much smaller (one molecule instead of 200
  nm pattern size in silicon wafers).
• It is estimated that NLO-computers would have a
  speed and dynamic memory increase of a factor of
  108, corresponding to 40 years of computer
  technology development.

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Known Structures
Poly(phenyleneethynylene)

• Advantages
• Conjugated polymer
• Organic Light Emitting Device (OLED)
• Suitable for non-linear optics
• Disadvantages
• Practically insoluble
• Fluorescence is self quenching because of
  p-stacking
• Air and moisture sensitive

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Target Polymer

• Advantages and putative advantages
• Conjugated polymer
• OLED, no self quenching alkyl double helix will
  prevent p-stacking
• Increased solubility
• Increased air stability
• Suitable for non-linear optics

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Models based on Target Polymer
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I
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Retrosynthetic Analysis of I
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Retrosynthetic Analysis of II
II
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Project Status I
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Project Status I
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Project Status I
Other approaches
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Project Status II
II
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Acknowledgements
F.K. thanks the Siegel group for useful
discussions and Kim Baldridge for ab initio
calculations.
References

• Heeger, MacDiarmid, Shirakawa, Angewandte Chemie
  Int. Ed., 40, 14, 2001
• Ziener et al., J. Org. Chem. 1997, 62, 6137-6143
• Wautelet et al., Macromolecules 1996, 29, 446-455
• Lee et al., J. Org. Chem. 2001, 66, 7155-7158