CONTENTS

A novel α-butyloxy-substituted tribenzotetraazachlorin-fullerene (TBTAC-C₆₀) conjugate has been synthesized by a mixed condensation of 1,2-dicyanofullerene and 3,6-dibutyloxyphthalonitrile in the presence of nickel chloride, and its spectroscopic properties have been compared with those of the β-butyloxy substituted is omer.

Absorption and magnetic circular dichroism (MCD) spectra, together with electrospray ionization mass spectral (ESI-MS) data are reported for the first two proteins, IsdH-NEAT domain 3 (IsdH-N3) and IsdB-NEAT domain 2 (IsdBN2), which are considered to be involved in heme transport following heme scavenging from the hemoglobin of the host in Staphylococcus aureus.

The roles of porphyrin/phthalocyanine in the photosensitized electron transfer processes in the supramolecular hybrids composed of nanocarbon materials such as fullerenes, single-walled carbon nanotubes, and carbon nanohorns are revealed with time-resolved fluorescence and absorption spectral methods. Porphyrin/phthalocyanine act as electron donors while the nanocarbon materials act as electron acceptors in the supramolecular hybrids.

In this manuscript, we are highlighting approaches to employ fullerenes and phthalocyanines, which are ideally suited for devising integrated, multi-component model systems to transmit and process solar energy. Specifically, we describe how the specific composition of phthalocyanines chromophores associated with C₆₀ – yielding artificial light harvesting antenna and reaction center mimics – have been elegantly utilized to tune the electronic couplings between donor and acceptor sites.

Using UV-visible absorption and resonance Raman (RR) scattering methods, electronic and vibrational data have been obtained for a high-valent molybdenum(V) oxo complex of 5,10,15-triphenylcorrole in a wide range of aprotic organic solvents. Optical absorption spectra exhibit a strong bathochromic effect of the corrole π-π* electronic transitions upon increasing solvent polarizability. The key vibrational mode, n(Mo^VO) stretch, is identified by ¹⁸O-isotope labeling of the terminal oxo ligand. This stretching vibration is strongly enhanced in resonance with the Soret electronic transition and its frequency is sensitive to solute-solvent interactions that weaken the Mo^VO triple bond by inhibiting O^2- → Mo⁵⁺ electron donation.

The impact of peripheral substitution with a strongly withdrawing fused ring group on the optical spectroscopy of metal phthalocyanines is analyzed based on a detailed study of the UV-visible absorption and MCD spectra of [9 (or 10), 16 (or 17), 23 (or 24)-tri-tert-butylimidophthalcyaninato]zinc(II) (ZnttbIPc) and the results of time dependent density functional theory (TD-DFT) calculations.

Organization of porphyrins on semiconducting electrodes plays an important role in solar energy conversion. Porphyrin/fullerene and porphyrin/carbon nanotube composites as well as asymmetrically π-extended porphyrin carboxylic acids have been as sembled onto semiconducting electrodes to develop efficient photoelectrochemical devices and solar cells.

Non-covalent porphyrin assemblies, in which singlet-singlet energy-transfer processes were characterized, are reviewed from the viewpoint of the mechanisms. Porphyrin dyads constructed through amidinium-carboxylate interactions are unique in that the through-bond mechanism may operate across the hydrogen bonding bridge.

The replacement of the heme cofactor with a synthetic one has been recognized as "chemical mutation" of hemoproteins. The synthetic cofactors include protoheme IXs equipped with a binding site or a function group at the terminal of heme propionates (I and II) and porphyrin derivatives with the different arrangements of pyrrole rings (III). This review will focus on the modification of hemoproteins using these synthetic cofactors.

Photoinduced electron transfer reactions of pheophytin-, phthalocyanine-, and porphyrin-fullerene dyads, in which donor and acceptor moieties are covalently linked to each other, are studied. The molecules form an intramolecular exciplex as a transient state before the formation of the charge separation state. The mechanism is discussed in frames of the Marcus electron transfer and the radiationless quantum transition theories.

Access to synthetic bromo-chlorins and bromo-bacteriochlorins requires scalable syntheses of the critical bromo-substituted hydrodipyrrin precursors. Refined syntheses of such precursors via a common intermediate, 4-bromo-2-(2-nitroethyl)-1-N-tosylpyrrole, have been achieved. The syntheses are efficient (with limited use of chromatography, chlorinated solvents, and excess materials), employ high concentrations, rely on crystallization, and afford improved yields of most steps. Supplementary Material

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