β-substituted donor-acceptor porphyrins: Synthesis, energy transfer and electrochemical redox properties

A series of β-functionalized D-A porphyrins have been synthesized via Suzuki coupling reaction. Synthesized free base porphyrins exhibited very high protonation constants (logβ2 = 9.59-10.45). An efficient Förster resonance through bond energy transfer (78-88%) from β-substituents to macrocyclic core was supported by steady state and time resolved fluorescence measurements. Free base β-trisubstituted porphyrins exhibited highest protonation constants so far known in the literature.329