Helical Self-Assembly of Optically Active Phthalocyanine Derivatives: Effect of ZnO Coordination Bond on Morphology and Handedness of Nanostructures

• Published in: Chemphyschem 2013-11, Vol.14 (16), p.3827-3833
• Main Authors: Zhang, Congcong, Jing, Lu, Lin, Sha, Hao, Zijuan, Tian, Jing, Zhang, Xiaomei, Zhu, Peihua
• Format: Article
• Language: English
• Subjects: Chemistry; chirality; Colloidal state and disperse state; Exact sciences and technology; General and physical chemistry; nanostructures; optically activity; phthalocyanine; self-assembly
• ISSN: 1439-4235; 1439-7641
• DOI: 10.1002/cphc.201300604

Two optically active phthalocyanine derivatives with eight peripheral chiral (S)‐4′‐(2‐methylbutoxy)biphenyl moieties on the β‐position of the phthalocyanine ring are synthesized. The circular dichroism (CD) spectra show signals in the Q absorption region for both compounds 1 and 2 in chloroform solution, indicating the effective chiral‐information transfer from the peripheral chiral (S)‐4′‐(2‐methylbutoxy)biphenyl side chains to the phthalocyanine chromophore at the molecular level. Their self‐assembling properties are further investigated by using electronic absorption and Fourier transform infrared spectroscopy, transmission electronic microscopy, scanning electronic microscopy, X‐ray diffraction, and X‐ray photoelectron spectroscopy. Experimental results reveal the effect of the metal‐coordination bond on molecular packing models in these nanostructures, which in turn results in the self‐assembled nanostructures with different morphologies, from nanosheets for 1 to helical nanofibers for 2. In addition, good semiconducting properties of the nanostructures fabricated from phthalocyanine derivatives 1 and 2 are revealed by current–voltage measurements. Single‐handed: Two optically active phthalocyanine derivatives with eight peripheral chiral (S)‐4′‐(2‐methylbutoxy)biphenyl moieties on the β‐position of the phthalocyanine ring are synthesized. A comparative investigation of the self‐assembly behavior of these two compounds indicate the influence of the metal‐coordination bond on the morphology and handedness of the self‐assembled nanostructures.