Vinylene-Linked Helical Covalent Organic Frameworks
Lu-Yao Wang1, Jie Feng1, Rui-Lei Wang1
1State Key Laboratory of Natural Product Chemistry, College of Chemistry and Chemical Engineering, Lanzhou Magnetic Resonance Center, Lanzhou University, Lanzhou, Gansu 730000, China.
Journal of the American Chemical Society
|June 2, 2026
Summary
Researchers synthesized single-handed helical covalent organic frameworks (V-heliCOFs) using a novel Siegrist olefination. These materials show strong circularly polarized luminescence, advancing chiral materials science.
Area of Science:
- Materials Science
- Organic Chemistry
- Supramolecular Chemistry
Background:
- Chirality is crucial for molecular recognition and optical properties.
- Synthesizing macroscopic chiral structures like helices in covalent organic frameworks (COFs) is challenging.
- Existing methods often rely on reversible imine chemistry, limiting stability and uniformity.
Purpose of the Study:
- To develop a new synthetic strategy for creating single-handed helical COFs.
- To investigate the chiroptical properties of these novel helical COFs.
- To establish a link between hierarchical structure and material performance.
Main Methods:
- Utilized an unprecedented Siegrist olefination strategy for COF synthesis.
- Formed highly uniform, single-handed macroscopic COF helices with micrometer dimensions.
- Characterized the resulting vinylene-linked helical COFs (V-heliCOFs) for structural and optical properties.
Main Results:
- Achieved the first synthesis of vinylene-linked helical COFs (V-heliCOFs).
- Observed emergent circularly polarized luminescence (CPL) with a record dissymmetric factor (|g_lum|) of 1.1 × 10⁻¹.
- Attained a high solid-state photoluminescence quantum yield (PLQY) of up to 45.7%.
Conclusions:
- The Siegrist olefination provides a robust pathway for crystalline COF helices.
- Hierarchical covalent assembly is effective for designing high-performance chiroptical materials.
- Synergistic coupling of emissive frameworks and helical architecture enhances chiroptical activity.
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