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The synthesis of new metal-free and zinc(II), cobalt(II) phthalocyanines substituted with four 4-(2-N'-cyanoethyl)aminoethylsulfanyl groups is described. The new compounds have been characterized by elemental analysis and IR, ¹H NMR and UV-vis spectroscopy.

A simple glass capillary-microreactor for studying the epoxidation of cyclohexene is described in this paper. Reaction conditions were optimized to achieve high reaction yield. The microreactor is easy to fabricate, fast and easy way for reliable catalyst screening in studying homogeneous oxidation reactions. Four different catalysts (i.e. manganese(II) and copper(II) metal complexes of Schiff and reduced Schiff base ligands) were synthesized and used. The reaction products were monitored by gas chromatography/mass spectrometry. The reaction performance was compared with conventional (batch scale) reaction. In both cases, catalytic activities and the product yields were found to be relatively higher for the copper(II) complexes when compared with the conventional route.

In this paper, electronic structures and third-order nonlinear optical (NLO) properties of a series of Pt–Pt bond-containing metal complexes have been calculated by using the density functional theory (DFT) combining with the sum-over-states (SOS) method. In order to check the reliability of this method, the electron correlations and basis sets have been compared. Our calculated results show that introduction of electron donor, thiophene ring and lengthing of organic conjugated ligand can enhance third-order NLO responses. The electronic structure analysis shows that the [Pt–Pt(H₂P(CH₂)PH₂)₂] fragment displays strong electron-withdrawing character in these systems. Meanwhile, the third-order NLO response of Pt–Pt bond also has been estimated by using TDDFT–SOS method. An enhancement of third-order NLO response has been observed because of the introduction of the Pt–Pt bond. This is mainly due to the intense and low-lying metal-to-ligand charge transfer (MLCT) and intraligand (IL) CT transitions.

When long alkylthio-substituted phthalocyaninato copper(II) complexes, (C_nS)₈PcCu, were rapidly prepared in an α-diol by using our developed see-through microwave reactor and/or a conventional hot stirrer, novel purple intermediates were selectively obtained instead of the expected green complex, (C_nS)₈PcCu, for some specific combinations of the reaction solvent and metal salt. The reaction conditions to obtain the purple intermediates were established and the unique molecular structure was clarified for a buthylthio-substituted intermediate by X-ray single crystal structure analysis.

Phthalocyanine (Pc)-based discotic liquid crystals could be prepared very rapidly by using our developed novel microwave-heating apparatus. It took only 10-20 min to synthesize these Pc metal complexes and metal-free Pc derivatives in an organic solvent (glycerin) by microwave irradiation, whereas it took 24-48 h to synthesize them by the conventional oil bath method. To our knowledge, it is the first example of metal-free Pc derivatives synthesized by microwave methods in an organic solvent. In the vast examples of Pc syntheses by conventional oil bath methods, the Pc metal complexes can be obtained in higher yields by “Template Effect” of the metal than the corresponding metal-free Pc derivatives. Therefore, we expected that the present Pc metal complexes (C_nS)₈PcCu (2) could be also prepared by microwave methods in higher yields than the metal-free Pc derivatives (C_nS)₈PcH₂ (1). Contrary to our expectation, the yields of the metal complexes (C_nS)₈PcCu (2) were lower than those of the metal-free derivatives (C_nS)₈PcH₂ (1). It is very interesting that this result by the microwave method is quite opposite to the results by conventional oil bath method. Hence, in this work we have focused our interest on the “Template Effect” in the syntheses of Pc derivatives by the microwave method in order to investigate the relationship between microwave heating and template effect. It is the first attempt in Pc syntheses by the microwave method.

Dipyrrins are valuable precursors to dyes [dipyrrinatoboron difluoride, bis(dipyrrinato)-zinc(II) complexes] and serve as ligands in a variety of self-assembled materials. Six new dipyrrin-containing architectures have been synthesized. The architectures include bis(dipyrrinato) complexes containing copper(II) or palladium(II), a dipyrrin bearing a protected phosphonic acid unit, a porphyrin bearing two dipyrrins in a trans configuration, a linear diphenylethyne-linked dipyrromethane-dipyrrin building block, and a triad composed of two zinc porphyrins joined via an intervening bis(dipyrrinato)copper(II) complex. Two porphodimethenatozinc complexes were prepared and found to have Φ_f ≤ 0.002 (in toluene at room temperature), which is substantially less than the analogous bis(dipyrrinato)zinc complexes. Taken together, the syntheses described herein should broaden access to dipyrrins for use as complexation motifs in supramolecular chemistry and as pigments in light-harvesting applications.

This account summarizes how the binding properties of a regular porphyrin macrocycle for large cations can be significantly modified and even tuned when the surrounding skeleton delivers at least one carboxylic acid group close to the N-core. While kinetics of metal insertion are drastically improved, unique dinuclear species can be obtained with a possible control of the nuclearity. The first incorporation of an α-core emitter radioisotope of particular interest for cancer therapy was recently demonstrated. All in all, this overhanging carboxylic acid strategy can be regarded as an alternative to either expanded porphyrins for the coordination of large cations from groups 14–15 (Pb^II, Bi^III) or contracted and isomeric porphyrins for the coordination of smaller cations from group 12 (Hg^II)

New series of iron, ruthenium, and osmium octabutoxynaphthalocyanines were synthesized by inserting corresponding metals into the metal-free octabutoxynaphthalocyanine. Although preparation of axial ligand-free iron octabutoxynaphthalocyanines was reported before, we could not reproduce the synthesis by following the reported method. We attributed the failure to the instability of the iron octabutoxynaphthalocyanines. Bis-ligation increased the stability of the iron complex but only sufficiently for characterization. The application of iron complexes will be limited by their instability. However, ruthenium and osmium formed stable complexes with this macrocycle ring but with significantly lower reaction yields. These new complexes were characterized by NMR, UV-vis, and mass spectrometry.

We have synthesized 34 novel homologous discotic liquid crystals, octakis(m-alkoxyphenoxy)phthalocyaninato metal(II) {abbreviated as (m-C_nOPhO)₈PcM (M = Co(1), Ni(2), Cu(3), Zn(4) and H₂(5); n = 8(a), 10(b), 12(c), 14(d), 16(e), 18(f) and 20(g))}, and investigated parity effect of the number of d-electrons on the stacking distances in their columnar mesophases. It was revealed from temperature-dependent wide angle X-ray diffraction studies that each of the cobalt(II) (d⁷) complexes (1a–1g) and the copper(II) (d⁹) complexes (3b–3g) showed a single hexagonal ordered columnar (Col_ho) mesophase with a very short stacking distance at 3.3 Å, and that the nickel(II) (d⁸) complexes (2a–2g) and the metal-free (d⁰) derivatives (5a–5g) showed a single pseudo-hexagonal ordered columnar (Col_rho) mesophase with a little bit longer stacking distances at 3.4 Å. Very interestingly, the nickel complex (2a) and metal-free derivatives (5a–5c) gave an extremely big (001) reflection peak with the second (002) reflection peak. Furthermore, the zinc(II) (d¹⁰) complexes (4a–4g) showed two different rectangular ordered columnar mesophases, Col_ro(P2/m) and Col_ro(P2₁/a), with a little bit longer stacking distance at 3.4 Å. Thus, the shorter stacking distance, 3.3 Å, appeared for the odd number of d-electrons, whereas the longer stacking distance, 3.4 Å, appeared for the even number of d-electrons. Hence, the stacking distances depend on parity of the number of d-electrons in the central metal(II). To our best knowledge, it is the first example of parity effect on the stacking distances in columnar mesophases.

Co(III) and Ga(III) complexes of 5,10-bis(pentafluorophenyl)corrole and 5,15-bis(pentafluorophenyl)corrole were synthesized by metalations with Co(OAc)₂ •4H₂O and GaCl₃, respectively. The structures of these complexes have been all unambiguously revealed by X-ray diffraction analysis. Their optical and electrochemical properties have been studied, which reveals small but distinctly different substituent effects depending upon the substitution positions.

A general design of a meso-aryl porphyrin for the formation of a 1D columnar stacking structure in the single crystal state is proposed. We found that 5,10-diphenyl- and 5,10-bis(pentafluorophenyl)porphyrin metal complexes (M = Zn, Ni) can stack in a complementary manner to form a 1D columnar stacking structure in the single crystals, while the corresponding freebase porphyrins displayed herringbone or dimeric orthogonal packing forms. The structural details of the obtained 1D columnar packing structures are discussed in comparison with precedented examples including 5,10-diphenylporphyrin Cu(II) and Ag(II) complexes, 5,10-diphenyl $N$-confused porphyrin Ag(III) complex and 5,10-bis(pentafluorophenyl)corrole.

The preparation and assessment of carbonic anhydrase and paraoxonase enzyme inhibition properties of 3-(2-(5-amino-4-(4-bromophenyl)-3-methyl-1H-pyrazol-1-yl)ethoxy)phthalonitrile (2) and its nitrogen-containing non-peripheral phthalocyanine derivatives (3 and 4) are reported for the first time. The new phthalonitrile and its phthalocyanine derivatives have been elucidated by FT-IR spectroscopy, ¹H-NMR, ${}^{13}$C-NMR, mass and UV-vis spectroscopy. The results demonstrated that all synthesized compounds moderately inhibited carbonic anhydrase and paraoxonase enzymes. Among the compounds, the most active ones were found to be compound 4 for PON (Ki : 0.14 $\mu$M), compound 3 for hCA I (Ki : 22.52 $\mu$M) and compound 1 for hCA II (Ki : 13.62 $\mu$M).

Inner- and peripheral-metal complexation behaviors of 5,10,15-tris(pentafluorophenyl)-20-pyrrolyl N-confused porphyrin (5) and its meso-pyrrolyl-bridged dimers (6-Ni and 7-Ni) were studied in this work. The resulting inner-Ag and peripheral-BF₂ complex (5-AgBF${}_2)$ exhibited the bathochromically shifted absorption feature ($\sim$772 nm), which was attributed to the BF₂ complexation. Furthermore, the bis-Ag/Ni complexes of dimer (6-Ag${}_2$Ni and 7-Ag${}_2$Ni) revealed remarkably lower energy bands in the deeper near-infrared ($i.e.$ NIR-II) region (${\lambda }_{\mathrm{\text{max}}}$ = 1226 and 1042 nm, respectively) through strong interchromophore interactions.

Corrole is a tetrapyrrolic ring-contracted porphyrin analog with one direct pyrrole-pyrrole link. The corrole macrocycle is electron-rich and easily stabilized in its one electron oxidized radical state, especially when coordinated to some specific metal ions. The corrole radicals and their complexes have demonstrated excellent air stability, amphoteric redox properties, and diversified spin configurations. Herein, we summarize the recent developments in the synthesis and properties of various corrole radicals, including $\pi$-monoradicals, antiferromagnetically and ferromagnetically coupled metal radicals, and $\pi$-diradicals. The regulation of spin, redox, and optical properties of corrole radicals by modifications to their periphery substituents, coordinated metals, and axial ligands is highlighted, which demonstrates their promising application prospects in spintronics, electronics, and energy-conversion materials.