Design, Synthesis, Self-assembly And Functional Properties Of Optically Active Phthalocyanine Derivatives

Porphyrin is very important participants in many life activities due to its typical macrocyclic conjugate electronic structure. As porphyrin analogues, phthalocyanine also owns optical, electrical and magnetic properties, which is the synthetic products. Furthermore, molecular structure of phthalocyanine is easier to modified as well as unique properties, which makes phthalocyanine widely used building blocks in supramolecular chemistry. Biological processes are simulated that porphyrin involves in by phthalocyanine to develop more applications. In recent years, the research of ordered supramolecular assembly with porphyrin and phthalocyanine as units has flourished. However, how to obtain supramolecular materials with ideal performance by adjusting the intermolecular forces resulting from precisely design and synthesize molecular remains a challenge. In the paper, two kinds of phthalocyanine with the same substiruents in different positions were synthesized. The effect of the substituents position on the functional properties of self-assembly supramolecular structure is investigated. This will provide a meaningful reference value for new type of functional materials of higher performance. In details, our reseach work has been focused on the following respects:(1) Helical self-assembly of optically active phthalocyanine derivatives in Mesophase and the effect of the position of chiral substituents on the liquid crystal propertiesDisc-like liquid crystals have received increasing attention inrecent years due to their one-dimensional columnar mesophaseand unique structural and electronic properties caused by theirstrong intermolecular π-π interaction. As porphyrin derivative, phthalocyanine has larger conjugated electronicmolecular structure, and often exhibits higher valuesfor the intrinsic charge carrier mobility for mesogens, which makethem becoming one of promising liquid crystal materials for opticaland electronic devices. In this chapter, two phthalocyanine derivatives with peripheral chiral (S)-2-methylbutanol moieties on the α-or β-positionof the phthalocyanine ring, namely{(1,8,15,22-tetra[(S)-2-methylbutoxy]} phthalocyaninatocopper complex (S)-CuPc(α-OC5H11)4(1)and{(2,3,9,10,16,17,23,24-octa[(S)-2-methylbutoxy]}Phthalo cyaninatocopper complex (S)-CuPc(β-OC5H11)g (2) were synthesized. Their helical self-assemblybehavior in mesophase were comparatively investigated byelectronic absorption and circular dichroismspectroscopy, differential scanningcalorimeter, polarized optical microscope and X-ray diffractiontechnique. In mesophase, (S)-CuPc(a-OCsH11)4(1) self-assembled into rectangular columnar liquidcrystals with left-handed fan texture. However, hexagonal columnar liquid crystals with well-ordered,rare, right-handed spherulites were formed from (S)-CuPc(β-OC2H11)8 (2). These results clearly indicatedthe effect of the position of chiral substituents on the handedness and mesophase textures of selfassembledliquid crystals and will be helpful towards rational design and preparation of chiral liquidcrystal materials.(2) Helical self-assembled of optically active phthalocyanine derivatives and the effect of the position of chiral substituents on the self-assembly propertiesThere are 16 positions available to substitute in the benzene ring of phthalocyanine ring around. Two types of positions can be divided, α-and β-. If the substituent is on the β-which is farther to the phthalocyanine ring, the effect on conjugated system deformation is rather small. But if the substituent is on the α-, the conjugated system deformation is often bigger. What is more, when eight-is linked to a-, saddle-shaped, distorted molecular structures is obtained. The optically active phthalocyanine derivatives whose substituent is on β- has been reported, while none is found with the substituent on the position of α-. In the chapter, An optically active phthalocyanine derivative with substitutions of eight a was originally synthesized. Its chiral transfer, expression and self-assembly property were compared with the analogous phthalocyanine derivative with substitutions of eight at molecular and supra-molecular level.