Wayne M. Campbell

The synthesis of dimeric porphyrins linked by a ferrocene

Abstract The synthesis and characterisation of dimeric porphyrins linked via a ferrocene are reported. The porphyrins are prepared using a Wittig reaction of a tetraphenylporphyrin-derived phosphonium salt and 1,1′-diformylferrocene. The reaction can be carried out in a stepwise manner to enable the preparation of heterobimetallic complexes.

The design and synthesis of porphyrin/oligiothiophene hybrid monomers

In an effort to build effective photovoltaic cells based on porphyrin-functionalised polythiophenes we have focused on synthetic routes to three monomer types. By controlling the geometric structure of the monomer, oxidation of these materials should produce polymers with different architectural structures, and as a result, different opto-electronic properties. Employing Wittig protocols allowed access to monomers in which the porphyrin moiety is connected to the beta-position of the thiophene via an alkene linkage. In addition, monomers were constructed using porphyrin condensation methods to afford alpha-thiophene meso-substituted porphryins. Another set of monomers was also prepared via porphyrin condensation routes, but instead utilising beta-formylthiophenes. By utilising different formyloligothiophenes we were able to generate a series of monomers that can be used to control the loading of the porphyrin in the polythiophene matrix.

A convenient synthesis of trimeric porphyrins with systematically variable geometry

Abstract A facile synthesis of trimeric porphyrins is reported. The geometry of the terminal porphyrins relative to the central macrocycle can be varied without significant changes to the synthetic procedure. This procedure also enables systematic control over the metallation states of the trimeric porphyrins.

Synthesis, reactivity and spectroscopy of ferrocene-functionalised porphyrins, with a conjugated connection between the ferrocene and the porphyrin core

Several new ferrocene-functionalised porphyrins and a ruthenocene-functionalised porphyrin have been synthesized and studied using electrochemistry, electronic absorbance and resonance Raman spectroelectrochemical techniques. The porphyrin and ferrocene are observed to have limited effect on each other with the properties of the porphyrin dominating the spectroscopy of these molecules.

Bis(ferrocenyl)porphyrins. Compounds with strong long-range metal–metal coupling†

The condensation of a dipyrromethane with ferrocene aldehyde leads to a single atropisomer of α,α-5,15-bis(ferrocenyl)-2,8,12,18-tetrabutyl-3,7,13,17-tetramethylporphyrin 1; electrochemistry of 1 and Ni-1 reveals two consecutive ferrocene-based one-electron oxidation waves, which are separated by 0.19 and 0.41 V, respectively.