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Updated: Apr 27, 2026
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Controlling the Size, Shape and Stability of Supramolecular Polymers in Water
Published on: August 2, 2012
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Axial chiral bisbenzophenazines: solid-state self-assembly via halide hydrogen bonds triggered by linear alkanes
Alison E Metz1, Erin E Podlesny, Patrick J Carroll
1Department of Chemistry, University of Pennsylvania , Philadelphia, Pennsylvania 19104, United States.
Journal of the American Chemical Society
|July 15, 2014
Summary
A novel axial chiral tetrachlorinated bisbenzo[a]phenazine exhibits reversible solid-state phase transitions triggered by alkanes. This discovery offers potential for new responsive materials and sensors.
Area of Science:
- Materials Science
- Supramolecular Chemistry
- Solid-State Chemistry
Background:
- Chiral organic molecules are crucial in various scientific fields.
- Phase transitions in solid-state materials can be triggered by external stimuli.
- Bisbenzo[a]phenazine derivatives are known for their unique electronic and structural properties.
Purpose of the Study:
- To discover and characterize a new axial chiral tetrachlorinated bisbenzo[a]phenazine.
- To investigate the solid-state phase transition behavior induced by alkanes.
- To elucidate the structural basis and reversibility of the observed phase transition.
Main Methods:
- Synthesis and characterization of the axial chiral tetrachlorinated bisbenzo[a]phenazine.
- Differential scanning calorimetry (DSC) to study phase transitions and guest-host interactions.
- Single crystal X-ray diffraction to determine the solid-state structure.
- Mechanical perturbation and photoimage processing for reversibility and colorimetric analysis.
Main Results:
- Discovery of an axial chiral tetrachlorinated bisbenzo[a]phenazine.
- Observation of an alkane-induced reversible solid-state phase transition from amorphous to polycrystalline form.
- Identification of phenolic OH···Cl hydrogen bonds as key determinants of pore structure.
- Correlation between alkane type and the degree of colorimetric change upon phase transition.
Conclusions:
- The discovered bisbenzo[a]phenazine exhibits tunable solid-state properties driven by guest inclusion.
- Weak hydrogen bonding plays a critical role in forming guest-responsive pores.
- The reversible, colorimetric phase transition suggests potential applications in sensing and data storage.
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