Directly meso meso linked subporphyrin dimer 5 and 7 were synthesized by Ni-mediated reductive coupling of the corresponding meso-bromosubporphyrins. Dimer 5 exhibited a largely perturbed absorption spectrum, a redshifted and enhanced fluorescence spectrum, higher oxidation potentials with a large potential difference between the first and second oxidation waves, and a long-lived large anisotropy of S1 state. Directly meso meso linked ZnII diporphyrin was prepared by AgI- promoted oxidative dimerization of ZnII porphyrin. The absorption spectrum shows a split Soret band, which can be interpreted in terms of simple exciton coupling of the two ZnII porphyrins without significant conjugative interaction. The high-resolution electrospray ionization time-of-flight (HR ESI-TOF) mass spectrum revealed an intense borenium cation peak at m/z 817.3095. These properties have been interpreted in terms of the effective conjugative interactions of the two subporphyrin units due to the small rotational barrier of the meso meso bond.
All Science Journal Classification (ASJC) codes
- Organic Chemistry