| Recently, more and more people have paid attention to the multiporphyrin and metal-multiporphyrins because they can be studied in modeling the natural photosynthetic reaction machinery and mimicking the biological light-harvesting, electron- and energy-transfer processes. They have been reseached in the areas of biology simulation, solar cells, homogeneous gas or out-phase active small molecules, gas sensor, LB film, crystalline material, nonlinear optical material today. They have also been used in the area of medicine by DNA cleavage, boronnuclear capture therapy and photodynamic therapy. Many scientists try to synthesize multiporphyrin with some special structure and function such as diporphyrin, triporphyrin, tetraporphyrin and multiporphyrin, especially diporphyrin since Anton et al. first synthesized multiporphyrin in 1972. However, they are reported about the triporphyrin rarely. In this paper, a series of esterphenylporphyrin trimer ligands and their transition metal Zn esterphenylporphyrin trimer complexes were synthesized and characterized by ways of IR, UV-Vis, elemental analysis, 1HNMR and MS, moreover, we have investigated these compounds by fluorescence spectroscopy, Resonance Raman spectra, cyclic voltammetry, and thermal studies. Our basical experiments will provide some helpful work for others in the area of the materials. The following contents are included in our work.1. Three porphyrin trimer ligands with different substituent group and their corresponding transition-metal complexes (Scheme 1) were synthesized by ourselves. We have investigated and analyzied their character in the means of UV-Vis, IR,1HNMR, and elemental analysis, MS and so on. Their properties about photochemistry, photophysic, electrochemistry and thermodynamic have been studied. The different substituent group influencing on their properties have also been studied. 1,4,7,10, R=CI 2,5,8,11,R=H 3,6,9,12, R=OCH3 Scheme 1 The synthesis routes of the porphyrin trimers(1) Fluorescence emission spectra: Comparing to the corresponding monomer, the fluorescence intensity increased and the shining range widened for both the porphyrin trimer ligands and their complexes with Zn. Because of different substitutented groups, the peak position red-shifted among three porphyrin trimer ligands. However, the quantum yield changed rulely because of the electron effect. This result is the same to the report before.(2)Electrochemical properties:The reductive reaction happened on the macrocycle of the porphyrin trimer ligands comparing to the corresponding monomer easily.(3)Raman spectra:The skeleton vibration bands of the porphyrin trimer ligands with different substitutented groups were similar. Therefore, there was an inapparent transformation about the Raman spectra of the porphyrin trimer ligands and Zn-porphyrin complexes.(4)The surface photovoltage properties:We have investigated their photophysical properties by the ways of SPS. The results indicated that porphyrin trimer ligands are very weaker and their complexes with Zn can be obtained with their corresponding UV-Vis spectrum. The much stronger in Fluorescence intensity, the weaker in the surface photovoltage.(5)Thermal property:Porphyrin trimers are verry stable under 200℃, and it will be a continuous process for the decomposition of the compound in the range of 300-600℃. They were decomposed completely at about 600℃. The connected group first was lost and the long chains on the benzene ring decomposed and the whole skeleton of the porphyrin collapsed at last.2. Six porphyrin trimer ligands with side chains of different length (Scheme 2) were synthesized, involving the preparation of aldehyde precursors by some multisteps by Williamson reaction. We have investigated and analyzied their structure character in the means of 1HNMR, UV-Vis, IR, and MS, elemental analysis and so on. Their properties about photochemistry, photophysic, electrochemistry and thermodynamic have been studied by fluorescence spectra, Raman spectra, SPS and TGA or DTA. It is weak about the length of alkoxy chain influencing their properties. Scheme 2. The synthesis routes of the porphyrin trimers with different alkoxyl chain length3. We have designed and synthesized our functionalporphyrin compound (P) and its metalloporphyrins which were based on porphyrin and 1-Hydroxy-2-naphthoic acid (Scheme 3). Synthesis of functional material based onporphyrin and 1-Hydroxy-2-naphthoic acid involves the preparation of acyl chloride by some multisteps by Williamson reaction. The compound and complexes were characterized by UV-vis and 1HNMR spectra, IR, 1HNMR, elemental analysis and MS. The photochemical have been studied by fluorescence spectra. Scheme 3. The synthesis routes of the different porphyrin P4. In this paper, a new color reagent (Scheme 4), tetra (4-hydroxy-3-ethoxyphenal) porphyrin (H2THEOPP) was synthesized and characterized by Uv spectra, infrared spectra, 1HNMR. Its characteristics with Pb was studied. In a medium of pH=11 with Triton-80, the complex of this reagent with Pb was formed. The apparent molar absorptance of the complex was 4 *105 L·mol·cm-1 [λ=473nm). Beer s law was obeyed in the range of 0～15μg/25mL for Pb. The reagent can be applied to the determination of Pb in the human hair. Scheme 4. The synthesis route of H2THEOPP...
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