| Abstract
| - The present paper reports uniqueness of a simple, programmed design of disk-shaped homochiral nickelphthalocyanine (Pc) molecules bearing four enantiomerically pure 1-(p-tolyl)ethylaminocarbonyl groupsat their peripheral positions, (Pc-(R) and Pc-(S)), and their controlled self-organization into mesoscopicsupramolecular helical fibers with a preferential handedness in solution and onto solid surfaces. Acombination of four fundamental intermolecular interactions, including quadruple hydrogen bonding,π−π stacking, homochiral interactions of the enantiopure bulky aralkyl entities, and noncoordinatingnature of nickel ion of the Pc molecules afforded a high thermal stability of the Pc self-assembly in chloroform(CHCl3), tetrahydrofuran, and o-dichlorobenzene and onto hydrophilic mica and hydrophobic HOPG surfaces.A higher-ordered helical self-assembly of Pc disks was observed in these solutions (∼200 Pc molecules),while the self-assembly was completely dissociated into monomeric species in N,N-dimethylformamidedue to a loss of hydrogen-bonding interactions between Pc molecules. Supramolecular chirality in thehierarchical self-assembly of Pc molecules originated from the presence of (R)- or (S)-chiral centers in theperipheral tails, which rotate noncovalently linked molecular building blocks to effectively form the helicalarchitectures. The helical Pc nanofibers dissolved in CHCl3, estimated to be ca. 70 nm from peak molecularweight obtained by SEC analysis, acts as a building block for higher-order helical fibers (ca. 1 μm) at singlemolecular level on the solid surfaces, as demonstrated by the dynamic force mode atomic force microscopy.Regardless of hydrophilic and hydrophobic substrates, the interaction between these Pc molecules and thesolid surfaces could not affect the morphology of helical assemblies, indicating a unique robustness of theseassemblies.
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