Optical properties and electronic structures of axially-ligated group 9 porphyrins

Abstract

A series of group 9 metal tetra-(p-tolyl)-porphyrin ( M(ttp) , M = Co(II) , Rh(III) , Ir(III)) complexes with axial phenyl substituents have been synthesized and characterized. An aryl bromide cleavage reaction of transition metal complexes was used to prepare the complexes from Co(ttp) , Rh(ttp) Cl and Ir(ttp)COCl , respectively. Magnetic circular dichroism (MCD) spectroscopy and TD-DFT calculations have been used to study trends in the optical spectra and electronic structures. The effect of introducing different para-substituents on the phenyl substituents was examined. During fluorescence emission studies, phosphorescence was observed for the Ir(III) complexes in the near infrared (NIR) region.