@misc{oai:niigata-u.repo.nii.ac.jp:00005302,
 author = {Kobayashi, Midori},
 month = {Mar},
 note = {Phthalocyanines (Pcs) of functional dye have peculiar optical, magnetic and electronic properties. Pcs have been widely used for dyes, pigments, liquid crystals, sensors, optical limiters, solar cells, and photosensitizer for photodynamic therapy of cancer. Pcs form aggregates in solution by stacking of Pc rings due to the π-π interaction between planar rings. The formation of higher aggregates results in lowering the solubility of Pcs. Thus, these are poorly-soluble or insoluble in most solvents. The substituted Pcs are synthesized to improve their solubility. It has been reported that these Pcs form aggregates which are dependent on concentrations, solvents and central metal ions of Pc ring. The understanding of aggregation equilibria of Pcs is very important because the properties of Pcs are significantly changed by the aggregation. The solvent effect on aggregation equilibria of Pcs by using one given Pc have scarecely been studied because of the limit owing to their solubility. In this research, amphiphilic phthalocyanine derivatives having linear polyethyleneoxide (-O-(CH_2CH_2)_n-C_mH_<2m+1>) (Fig. 1) were synthesized and solvent effect on their aggregation equilibria and structure of the aggregates were elucidated. Complex formation of Pc ring and polyethyleneoxide side chains with alkali metal ions and structures of these complexes were also elucidated. Fig. 1. Structure of amphiphilic phthalocyanine derivatives substituted by polyethyleneoxide. (M=2H^+ or Cu^<2+>, R=-C_<12>H_<25> or -CH_3) The Pcs form aggregates successively as given by the following equation. The aggregates are stacked face to face between the Pc rings and their slippage between the Pcs in very small. Pc+Pc_n⇔Pc_<n+1> In the coordinating solvents, the aggregation of Pcs is promoted by the increase in DN of solvent. DN is the indication of coordination ability of the solvent molecule to cationic moiety of solute such as the metal ion. Thus, if the coordination of solvent to the central cation of Pcs, Cu^<2+> or 2H^+, is the dominant factor of the solvation of Pcs, the solvent of lager DN must promote the cleavage of aggregate to monomer. But the opposite tendency of the experimental results is explained by the decreases in accepting property of solvent by the increase in DN. In the non-coordinating solvents, the monomerization of Pcs is promoted by the increase in E_T(30) value of solvent. This parameter is an indicator of the interaction of the solvent molecule to an anionic or electron donating part of solute, i.e., the index of the electron pair accepting property of the solvent. Thus, the increase in E_T(30) value of solvent results in the strengthening of the salvation to the ethylene oxide moiety, and enhances the cleavage of the aggregates. The Pc ring moiety and ethylene oxide chain moiety of Pc derivatives form different structures of complexes depending on the ionic radii of alkali metal ions (Li^+, Na^+ and K^+). The ethylene oxide chain coordinates the alkali metal ion by surrounding it (Fig. 2). Complexation ability of ethylene oxide chain increases in the following order, Li^+ < Na^+ < K^+, because of the size fitting of ionic radius of metal ion with the cavity size of helical ethylene oxide chain. On the other hand, Pc ring coordinates alkali metal ion and the structures of them are different depending on the suitability of cavity size of Pc ring and ionic radius. In case of the smaller Li^+ ion, Pc forms a monolithiumphthalocyanine. Li^+ ion coordinates into the Pc ring cavity because ionic radius of Li^+ ion fits to the cavity size of Pc ring (Fig. 3(a)). In the case of larger Na^+ and K^+ ions, Pc form disodium and dipotassium phthalocyanines and these ions are located on the top and bottom of the Pc ring, i.e., so called sitting a top (SAT) complex., 新潟大学大学院自然科学研究科, 平成24年3月23日, 新大院博（理）甲第342号, 新大院博（理）甲第342号},
 title = {Synthesis and Properties of Amphiphilic Phthalocyanine Derivatives Substituted by Polyethyleneoxide},
 year = {2012}
}