Synthesis And Properties Of Porphyrins And Their Derivatives

Porphyrin compounds are a kind of large ring compounds with conjugate structure which widely exist in nature and biological and plays an important role in the process of life.Due to the highly conjugated porphyrin system,it is highly susceptible to electronic of methyl and pyrrole ring. If change the substituent, introduce metal ions, or change of different axial ligands, the porphyrin show different optical properties and functions.In this paper,we design porphyrin as chromophores, ethoxy chain as binding site, introduced amino in the end of the ethoxy chain to coordinate with the center ion of porphyrin. Controlling the molecular configuration by the length of ethoxy chain,study the selective effects of porphyrin on heavy metals, designed and synthesized four sensing molecule(6a, 6b, 6c, 6d).Porphyrin ring was synthesized by hydroxyl benzaldehyde,benzaldehyde and pyrrole refluxed in propionic acid. As glycol, sulfoxide chloride and potassium phthalimide chloridized and replaced to single chloride, target molecules was synthesized after two fragment condensation. Using analytical means such as 1H NMR, MS, HSQC and COSY on the characterization of part of the intermediates and the target molecule structure. Due to the chemical shift of hydrogen atoms on amino and ethoxy chain has different degrees of high field displacement which means amino coordinate with the center ion and affected by the porphyrin ring current. Meanwhile, combined with coupling signal of two-dimensional two-dimensional nuclear magnetic and the relative abundance of the mass spectrometry for target molecules, we judge the target molecules were mainly existed in the form of monomer, and the content of dimer is negligible.Researching for how the Na+, K+, Mg2+, Ca2+, Cu2+, Zn2+, Hg2+, Cd2+, Pb2+ and Ni2+ metal ions effect with target molecular through nuclear magnetic titration and uv titration experiment.The experimental results show that Hg2+ and Pb2+ have strong combining capacity with the target molecular, and the binding constant increases with the increase of ethoxy chain;the binding constant of Ca2+ is decreased with the increase of ethoxy chain. In addition, Cd2+, Mg2+, Na+, Zn2+ had little effect.May be it is result in matching of the molecule configuration of target molecular and metal ion in shape, and the result of the hard and sof nature of t acid-base.As described in the end, four ethoxy chain modification of porphyrin compounds(6a,6b,6c,6d), and comfirm its chemical structure and molecular conformation was designed and synthesized, preliminary explore its effect on the combination of heavy metal ions, providing a theoretical basis and data reference for heavy metal detection.