Self-Assembly and Liquid-Crystalline Properties of 5-Fluoroalkylporphyrins

✍ Scribed by Li-Mei Jin; Juan-Juan Yin; Liang Chen; Jin-Ming Zhou; Ji-Chang Xiao; Can-Cheng Guo; Qing-Yun Chen

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 684 KB
• Volume: 12
• Category: Article
• ISSN: 0947-6539
• DOI: 10.1002/chem.200600487

✦ Synopsis

Abstract

We report three crystal structures of a synthetic 5‐fluoroalkylporphyrin molecule that was programmed for self‐assembly. All the X‐ray structures of zincated and free‐base porphyrins Zn2 b, Zn5 a, and 2 b revealed rigorous π–π stacking and extremely hydrophobic interactions. Other the other hand, the strong aggregation of 5‐fluoroalkylporphyrins in solution was also found. Interestingly, the regular nanopore formation of the 5‐fluoroalkylporphyrin was visualized by atomic force microscopy (AFM). Importantly, the 5‐fluoroalkylporphyrins possess liquid‐crystalline properties that were confirmed by using a combination of differential scanning calorimetry (DSC) and polarizing optical microscopy (POM) techniques. By comparison, the self‐assembly of non‐fluorine‐containing porphyrins with similar structure showed much lower aggregation ability, as investigated by NMR techniques. Additionally, no birefringent mesophase was observed for the non‐fluorine‐containing porphyrin.