Synthesis and Raman, Electrochemical, Fluorescence Studies of Free-Base and Transition Metal Porphyrin-Nicacid Dyads With Different Substituent Groups

A series of free-base porphyrin-nicacid dyads with different meso-substituents and some transition metal complexes were synthesized and characterized by means of UV–vis, IR, and 1H NMR spectroscopies, and elemental analysis. The properties of nicacid linked with porphyrin dyads were studied as a new intramolecular electron transfer system. The effects of different metal ions and different substituent groups on the properties of the porphyrin-nicacid dyads have been investigated. The studies on the electrochemical and fluorescence spectra, and Raman spectra, showed that different substituents and metal ions affect the properties of the compounds in different ways.