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Ordered carbonaceous frameworks (OCFs) are a new class of carbon materials with a three-dimensional ordered structure synthesized by simple carbonization of metalloporphyrin crystals with polymerizable moieties. Carbonization

While the functions of carbon materials with precisely controlled nanostructures have been reported in many studies, their chiral discriminating abilities have not been reported yet. Herein, chiral discrimination is achieved using helical carbon materials devoid of chiral attachments. A Fe

Carbon materials with 3D-ordered nanopores doped with metals and nitrogen were synthesized from strategically designed phthalocyanines via the self-assembly of Fe3O4 nanoparticles. Their catalytic activity was determined by the doped metals.

A reaction of Ni(ClO4)2·6H2O with a tripodal ligand having two di(tert-butyl)phenol moieties, H2tbuL, and 1 equivalent of triethylamine in CH2Cl2/CH3OH (1 : 1, v/v) under N2 gave a NiII-(phenol)(phenolate) complex, [Ni(HtbuL)(CH3OH)2]ClO4. The formation of the NiII-phenoxyl radical complex by O2 was observed in the reaction of this complex in the solid state. On the other hand, the NiII-phenoxyl radical complex [Ni(Me2NL)(CH3OH)2]ClO4 was obtained by the reaction of H2Me2NL having a p-(dimethylamino)phenol moiety with Ni(ClO4)2·6H2O in a similar procedure under O2, through the oxidation of the NiII-(phenol)(phenolate) complex. However, a direct redox reaction of the NiII ion could not be detected in the phenoxyl radical formation. The results of the reaction kinetics, XAS and X-ray structure analyses suggested that the O2 oxidation from the NiII-(phenol)(phenolate) complex to the NiII-phenoxyl radical complex occurs via the proton transfer–electron transfer (PT–ET) type mechanism of the phenol moiety weakly coordinated to the nickel ion.

Dibenzo[n]phenacenes (DBnP, n = 5–7) were applied to the active layers of p-channel FETs and their effective mobilities were evaluated to demonstrate that C2h-symmetrical DB6P showed superior performance to the C2v-symmetrical homologues.

To gain insight into the singlet oxygen (1O2) generation properties of supramolecular complexes of cyclic free-base porphyrin dimer with fullerene C60, we evaluated the 1O2 quantum yield (ΦΔ) and rate constant (Kobs) of 1O2 generation for a cyclic free-base porphyrin dimer (CPD) linked by butadiyne bearing four 4-pyridyl groups and its inclusion complex (C60⊂CPD) with C60. We demonstrate that CPD and C60⊂CPD possess the ability to generate 1O2 under visible light irradiation. Moreover, it was found that the ΦΔ value of C60⊂CPD is lower than that of CPD. Based on the kinetic and thermodynamic consideration concerning the electron transfer processes between the porphyrin dimer and C60, this work revealed that the lower ΦΔ value of the C60 inclusion complex would be attributed to the formation of the charge-separated state C60·−-CPD·+, leading to a low intersystem crossing (ISC) efficiency for the formation of the triplet excited state 3(CPD)*.

Cyclic free-base porphyrin dimers (H4-C4-CPDPy(TEO) and H4-Ptz-CPDPy(TEO)) linked by butadiyne or phenothiazine bearing four 4-pyridyl groups and their inclusion complexes (C60⊂H4-C4-CPDPy(TEO) and C60⊂H4-Ptz-CPDPy(TEO)) with fullerene C60 have been applied to dye-sensitized solar cells (DSSCs) as a new class of porphyrin dye sensitizers with pyridyl anchoring groups for attachment on a TiO2 electrode. The FTIR spectra of the porphyrin dimers adsorbed on TiO2 nanoparticles demonstrated that these porphyrin dimers are adsorbed on the TiO2 surface through the formation of hydrogen bonding of pyridyl groups and/or pyridinium ions at Bronsted acid sites on the TiO2 surface. The adsorption amount of the porphyrin dimers adsorbed on the TiO2 electrode is 2.0 × 1017 molecules per cm2, that is, the adsorption amount of the porphyrin unit is 4.0 × 1017 cm−2, which is higher than that of dye sensitizers with pyridyl groups reported so far. The photovoltaic performance of DSSCs based on phenothiazine-bridged cyclic porphyrin dimer H4-Ptz-CPDPy(TEO) is higher than that of DSSCs based on butadiyne-linked cyclic porphyrin dimer H4-C4-CPDPy(TEO). Moreover, the photovoltaic performances of DSSCs based on cyclic free-base porphyrin dimers are higher than those of DSSCs based on their C60 inclusion complexes C60⊂H4-C4-CPDPy(TEO) and C60⊂H4-Ptz-CPDPy(TEO). On the basis of the electrochemical measurements (voltammetry and electrochemical impedance spectroscopy) and the transient absorption spectroscopy, the differences in the photovoltaic performances among these cyclic free-base porphyrin dimers are discussed from kinetic and thermodynamic considerations concerning the electron transfer processes in DSSCs.

Compounds 1a and 1b which have a 1,10-phenanthroline moiety, were synthesized in order to form a helical structure in the presence of Cu(I), and a boronic acid moiety with which to bind a saccharide at the chain end. When saccharides were added, the Cu(I) complexes (as 1a2·Cu(I) and 1b2·Cu(I)) gave the CD-active species reflecting the absolute configurational structure of saccharides. Thus, the P versus M helicity of the complexes can be controlled by the boronic acid–saccharide interaction. The results show that the terminal boronic acid group is useful to create the chiral helical structure and the total helicity is governed by the chirality of the boronic acid-bound saccharide.

Iron porphyrins that are modified on both faces by chiral binaphthalenes catalysed asymmetric oxidation of sulphides in fair to good enantiomeric excesses and excellent turnover numbers of the catalysts in the presence of 1-methylimidazole.

Lithium ion encapsulated [60]fullerene (Li+@C60) is included within a free base and nickel complex of a cyclic porphyrin dimer (M-CPDPy, M = H4 and Ni2) to afford supramolecules (Li+@C60⊂M-CPDPy) in a polar solvent (benzonitrile) with the association constants of 2.6 × 105 M−1 and 3.5 × 105 M−1, respectively. From the electrochemical analysis, the energies of the charge-separated (CS) states are estimated to be 1.07 eV for Li+@C60⊂H4-CPDPy and 1.20 eV for Li+@C60⊂Ni2-CPDPy. Both values are lower than the triplet excited energies of the fullerene and porphyrin. Upon the photoexcitation at the Q-band of the porphyrin chromophore of Li+@C60⊂H4-CPDPy, electron transfer from the triplet excited state of the free base porphyrin to Li+@C60 occurs to produce the CS state. Li+@C60⊂Ni2-CPDPy also undergoes photoinduced electron transfer to produce the CS state. The lifetimes of the resulting CS states are 0.50 ms for Li+@C60⊂H4-CPDPy and 0.67 ms for Li+@C60⊂Ni2-CPDPy. These remarkably long CS lifetimes are the best values ever reported for non-covalent porphyrin-fullerene supramolecules in solution and are attributable to the lower CS energies than the triplet energy of each chromophore.

As an active site model of cytochrome c oxidase, a new covalently-linked binuclear complex with three imidazole ligands for copper, heme–tris(imidazolyl)methane copper, was prepared and spectroscopically characterized.