A Heteromeric Carboxylic Acid Based Single-Crystalline Crosslinked Organic Framework
Rongran Liang1, Jayanta Samanta1, Baihao Shao1
1Department of Chemistry, Dartmouth College, 6128 Burke Laboratory, Hanover, NH, 03755, USA.
Angewandte Chemie (International Ed. in English)
|August 11, 2021
Summary
Researchers developed a novel large-pore single-crystalline framework (HCOF-101) using photo-crosslinked hydrogen-bonded molecular crystals. This framework successfully hosts and enables reversible isomerization of a photoswitch, demonstrating potential for optical data storage.
Area of Science:
- Materials Science
- Crystallography
- Supramolecular Chemistry
Background:
- Large-pore single-crystalline frameworks are crucial for understanding structure-property relationships.
- Photo-crosslinking hydrogen-bonded molecular crystals is an emerging strategy for framework construction.
- Carboxylic acid building blocks can form large-pore networks but often lead to interpenetrated or non-porous structures.
Purpose of the Study:
- To construct a non-interpenetrated, large-pore single-crystalline framework using heteromeric carboxylic acid dimers.
- To investigate the framework's ability to host and interact with guest molecules, specifically a photoswitch.
- To explore the potential of the developed framework for applications such as optical information storage.
Main Methods:
- Synthesis of a non-interpenetrated molecular crystal precursor using heteromeric carboxylic acid dimers.
- Photo-crosslinking of the crystal precursor with dithiols to form the hydrogen-bonded crosslinked organic framework (HCOF-101).
- X-ray diffraction analysis to determine the crystal structure and network topology of HCOF-101.
- Inclusion of a hydrazone photoswitch within the framework's porous channels.
Main Results:
- Successful construction of a large-pore single-crystalline hydrogen-bonded crosslinked organic framework, HCOF-101.
- X-ray diffraction revealed HCOF-101 as an interlayer-connected hexagonal network with flexible linkages and large porous channels.
- Multicycle reversible Z/E-isomerization of the hosted hydrazone photoswitch was observed within the framework.
Conclusions:
- Heteromeric carboxylic acid dimers enable the construction of non-interpenetrated, large-pore single-crystalline frameworks.
- HCOF-101 exhibits flexible porous channels suitable for hosting guest molecules like photoswitches.
- The reversible isomerization within HCOF-101 highlights its potential for optical information storage applications.
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