Abstract
Three isomers of meso-tetrapyridylporphins, i. e. tetra (2-pyridyl)-(2), (3-pyridyl)-(3), and (4-pyridyl)-(4), porphin have been synthesized. They were soluble in acetic acid, chloroform and acidic aqueous solvents. Solubilities in chloroform, dimethylformamide and pyridine were in the order 3>2>4. Comparison of the visible spectra indicated that the intensities of the bands due to 0-0 transitions decreased (3>4>2) with an increase of the electron-withdrawing character of the pyridyl substituent. The copper (II) and zinc (II) complexes of 2 and 3 have been prepared. Infrared and nuclear magnetic resonance spectra and their assignments of the porphins and/or the metal complexes were described.
