Six centrosymmetric D-(p-A) 3 structural triphenylamine derivatives that can be used as two-photon photopolymerization and optical data storage chromophores, tris[4-(4-pyridylethenyl)phenyl]amine (1), tris [4-(2-pyridylethenyl)phenyl]amine (2), tris(4-cyanoethenylphenyl)amine (3), tris[4-butylacrylatephenyl]amine (4), tris[4-methylacrylatephenyl]amine (5) and tris[4-acrylicethenylphenyl]amine (6), have been successfully synthesized via a triple palladium-catalyzed Heck coupling reaction, and the novel chromophores were fully characterized by elemental analysis, IR, 1 H-NMR and ESIMS. The structure for 3 was determined by single crystal X-ray diffraction study. One-and two-photon absorption and fluorescence in various solvents were experimentally investigated. Two-photon initiated polymerization microfabrication and optical data recording experiments were carried out under 780 nm laser radiation, and the possible polymerization mechanism is discussed based on theoretical calculations. All the six chromophores have relatively large two-photon absorption crosssections, and exhibit optical memory and highly efficient two-photon initiated polymerization abilities.

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The reduction of complex precursor cobalt bis(4-pyridine carboxylate) tetrahydrate under a magnetic field was investigated. Particular cobalt potato-like hierarchical structures (10−50 μm) composed of nanoflakes (10−20 nm in thickness) were obtained without a magnetic field applied due to spherical clusters consisting of cobalt complexes formed before reduction. When a 0.35 T external magnetic field was applied, one-dimensional microchains comprising potato-like cobalt microspheres were formed via the same route, which has a length of hundreds of microns, while the assembly of nanoflakes induced by the magnetic field was not observed. The experiment results indicate that the interactions among the complex molecules (or nanoflakes) are stronger than the magnetic interaction between the magnetic dipolar and the applied magnetic field. As a result, the spherical clusters of cobalt complex and the potato-like spheres are stable under the applied magnetic field. The applied field determines the assembly of potato-like spheres to form one-dimensional microchains only.

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