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An efficient electrosynthetic pathway was developed for the synthesis of a fully substituted zinc octaethylporphyrin as a precursor, permitting the synthesis of pentaporphyrin in an independent second step. This technique has the primary advantage of allowing the preparation of a porphyrin block involving a central subunit whose electronic characteristics are very much different from those of the four peripheral chromophores.

The electrochemical characteristics of covalent derivatives of the higher fullerenes C70, C76, C2v-C78, and D3-C78, with bis(alkoxycarbonyl)methano addends, were studied by cyclic voltammetry and/or steady-state voltammetry. Several characteristics were found to be common to lower adducts (mono- to tetrakisadducts) of all the fullerenes examined including C60. All derivatives underwent several electrochemical reduction and one or two oxidation steps.

Electrochemical analysis and ab initio calculations were done to examine the structure of donor- and/or acceptor-substituted tetraethynylethenes (TEEs) and to assess the ability of their conjugated carbon core to induce electronic communication between pendant functionality. The results revealed that the presence of one redox center on the TEE core exerts negligible effect on the redox characteristics of the other centers. It was also found that the alkyne moieties are responsible for the delocalization of charges into the carbon framework after electrochemical reduction. Such charge delocalization, in turn, leads to cis-trans isomerization.

Trinuclear copper(II/I) complexes of hexakis(bipyridyl)cyclotriveratrylene, (CTV) ligand exhibit redox controled conformational isomerism. Electrochemical method, along with 1H-NMR and mass spectroscopy, characterize these complexes. The ligand catechol gives only one bistable complex with Cu(II), which helps to identify the conformations observed for CTV complexes. The variable temperature cyclic voltametry gives thermodynamic data and equilibrium constant. The effect of noncoordinating and coordinating solvents is also discussed.

The electrochemical and spectroscopic characteristics of three iron corroles were examined. Benzonitrile, dichloromethane and pyridine containing 0.1M tetra-n-butylammoniun perchlorate or tetra-n-ethylammonium hexafluorophosphate were used as supporting electrolyte. An iron(IV) tetrapyrrole pi cation radical has been isolated and characterized as a perchlorate. The strong antiferromagnetic coupling between the iron(IV) center and the singly oxidized corrole macrocycle has been confirmed by Mossbauer, X-ray crystallographic and magnetic susceptibility studies.

Synthetic procedures enable the preparation of (OEC)Fe(III)(NO), the first neutral iron(III) nitrosyl tetrapyrrole, with OEC being the trianion of 2,3,7,8,12,13,17,18-octaethylcorrole. The complex undergoes up to three oxidations, and the first two reversible oxidations occur stepwise at the corrole macrocycle producing a stable iron(III)pi-cation radical and dication. Both oxidation products have a coordinated NO axial ligand, and cyclic voltammetric studies reveal the occurrence of two one-electron reductions of the complex.