Stereospecific Synthesis and Photophysical Properties of Propeller-Shaped C90 H48 PAH
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Updated: Jan 3, 2026

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
Fangyuan Zhang1, Evripidis Michail1, Fridolin Saal1
1Institute of Organic Chemistry, University of Würzburg, Am Hubland, 97074, Würzburg, Germany.
Abstract:
Herein, we have synthesized an enantiomerically pure propeller-shaped PAH, C90 H48 , possessing three [7]helicene and three [5]helicene subunits. This compound can be obtained in gram quantities in a straightforward manner. The photophysical and chiroptical properties were investigated using UV/Vis absorption and emission, optical rotation and circular dichroism spectroscopy, supported by DFT calculations. The nonlinear optical properties were investigated by two-photon absorption measurements using linearly and circularly polarized light. The extremely twisted structure and packing of the homochiral compound were investigated by single-crystal X-ray diffraction analysis.
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