An efficient method for the synthesis of C-C connected phthalocyanine-porphyrin oligomers

An efficient one-step method for the synthesis of covalently linked phthalocyanine-porphyrin (Pc-Por) hetero-dyads and Pc-Por-Pc hetero-triads, connected directly through C-C bonds, is presented. The procedure utilizes a Pd-mediated Suzuki cross-coupling reaction of a Pc-boronate synthon and a halogenated porphyrin. The two chromophores are directly linked, without spacer, through the β-pyrrolic-, meso-, and para-position of the meso-phenyl group of the porphyrins. The electronic absorption spectrum of the Pc-Por-Pc triad shows red-shifted, split Q-bands reflecting energy transfer.