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A series of the new monophthalocyaninato lanthanide complexes, [Ln(Pc)(cyclen)]Cl (Ln = Y, Tb, Dy, Ho, Er, Tm, and Yb; Pc = phthalocyaninato; cyclen = 1,4,7,10-tetraazacyclododecane) was synthesized and characterized. The crystallographic study of monophthalocyaninato complexes with a capping macrocyclic ligand having no π-conjugation while keeping the 4-fold symmetry is presented for the first time. All the six complexes were crystallized in a tetragonal structure of the I4mm space group. In addition to this, the Tb complex exhibited a triclinic crystal structure of the P1 space group. All of the complexes are isostructural, where both Pc and cyclen are coordinated to an Ln3+ ion giving an eight-coordinate square-antiprismatic geometry. The skew angle between the Pc and cyclen ligands was 45° in the tetragonal crystals and 41.5° in the triclinic crystal. The metal–nitrogen bond lengths were shorter on the Pc ligand side than cyclen side, presumably due to the difference in the charges of the ligands and...

Mixed condensation of tetramethylsuccinonitrile and either 2,3-dicyano-5,6-diethylpyrazine, 2,3-dicyanopyridine, or 3,4-pyridinedicarboximide in the presence of nickel chloride forms novel pyrazine-, 2,3-pyridine-, or 3,4-pyridine-ring-fused tetraazachlorin (TAC), tetraazabacteriochlorin (TABC), and tetraazaisobacteriochlorin (TAiBC) derivatives. All possible structural isomers were separated using repeated thin-layer chromatography and have been investigated by absorption and magnetic circular dichroism spectroscopy. Similarly to previously reported TAC analogues, the TAC and TABC derivatives show large splitting of the Q band, while a single, intense absorption band is observed for the TAiBC derivatives. Although the absorption spectra are practically identical in shape for the separated structural isomers of TACs and TABCs, the Q-band maxima of the TAiBCs depend significantly on their structures. The observed spectroscopic properties were interpreted on the basis of electrochemical data and the results of (time-dependent) DFT calculations.

The reaction of a double-decker phthalocyanine (Pc) complex, bis(phthalocyaninato)lutetium ([LuPc(2)](-)), with cadmium acetate at 400 degrees C for 30 min under argon provided the first example of a discrete quadruple-decker Pc complex, 1. The structure of 1 was unambiguously determined through the use of high-resolution mass spectrometry, elemental analysis, and NMR techniques such as (1)H-(1)H COSY, (13)C-(1)H COSY, and NOE experiments. The absorption and magnetic circular dichroism spectra of 1 resembled those of [LuPc(2)](-) and [Lu(2)Pc(3)] rather than those of the neutral double-decker species [LuPc(2)](0), since the formal charge on each Pc moiety is 2-. Electrochemical measurements exhibited a stacking effect based on the delocalization of the holes or electrons introduced by oxidation or reduction, respectively, over the entire complex.