Towards triptycene functionalization and triptycene-linked porphyrin arrays

Area of Science:

• Organic Chemistry
• Materials Science
• Supramolecular Chemistry

Background:

• Triptycene derivatives are explored for their rigid, three-dimensional structures.
• Multichromophoric arrays are crucial for applications in molecular electronics and light harvesting.
• Rigid linkers are essential for controlling the distance and orientation between chromophores.

Purpose of the Study:

• To investigate 9,10-diethynyltriptycene as a rigid isolating unit in synthesizing multichromophoric arrays.
• To synthesize and characterize novel porphyrin-triptycene and boron dipyrromethene (BODIPY)-triptycene conjugates.
• To report the first linearly connected porphyrin dimer linked via the bridgehead carbons of a triptycene scaffold.

Main Methods:

• Sonogashira cross-coupling reactions were employed to functionalize the triptycene scaffold.
• Synthesis of symmetric and unsymmetric porphyrin-triptycene complexes.
• Single crystal X-ray diffraction analysis was used to confirm the molecular structure and linearity.
• UV-Vis absorption and fluorescence spectroscopy were utilized for initial photophysical studies.

Main Results:

• Successful synthesis of multichromophoric arrays using 9,10-diethynyltriptycene as a rigid linker.
• Demonstration of the first linearly connected porphyrin dimer through triptycene bridgehead carbons.
• X-ray crystallography confirmed the linear arrangement and rigidity of the triptycene-linked porphyrin dimer.
• Preliminary photophysical studies indicated the potential of triptycene as an isolating linker for electron transfer.

Conclusions:

• 9,10-diethynyltriptycene serves as an effective rigid isolating unit for constructing multichromophoric systems.
• The synthesized linearly connected porphyrin dimers represent a new class of supramolecular architectures.
• Triptycene-based linkers show promise for applications in studying electron transfer phenomena in molecular systems.