Helical Self‐Assembly of Optically Active Phthalocyanine Derivatives Bearing Four Optically Active (S)‐2‐Methylbutoxy Moieties at the α Position of the Phthalocyanine Ring

Abstract

AbstractThree phthalocyanine derivatives with four peripheral chiral (S)‐2‐methylbutoxy moieties at the α or β positions of the phthalocyanine ring have been synthesized. The CD spectra of compounds 1 and 2, each containing four peripheral chiral (S)‐2‐methylbutoxy moieties at the α positions of the phthalocyanine ring, show CD signals in the Q‐absorption region of the phthalocyanine chromophores. However, no CD signal was observed in the whole absorption region for compound 3, which contains four peripheral chiral (S)‐2‐methylbutoxy moieties at the β positions of the phthalocyanine ring. These results indicate the influence of the position of the chiral substituents on the chiral transfer and expression at a molecular level. Further investigation of the self‐assembly behavior of compounds 1 and 2 revealed that the metal‐free phthalocyanine 1 self‐assembles into a nanocube whereas its zinc congener, [(S)‐ZnPc(α‐OC5H11)4] (2), self‐assembles into helical nanobelts, which implies an effect of metal coordination on the morphology and handedness of the self‐assembled nanostructures.