SYNTHESIS AND PROPERTIES OF OSMIUM(II) PORPHYRIN OLIGOMERS LINKED BY 3-PYRIDYLPORPHYRINS

Two kinds of new osmium(II) porphyrin oligomers having tetraarylporphy rins with 3-pyridyl and phenyl groups as axial or a bridging ligands, Dimer-Oblique and cis-Trimer-Oblique were synthesized and characterize d by spectral methods. In cis-Trimer-Oblique. atropisomerization cause d by the rotation of pyridyl groups was observed by H-1 NMR spectral m easurements at room temperature. [GRAPHICS] clear organoaluminum compo und {[AlMe2](3)[CH3C(CH2NH)(2)(CH2O)](2)Al} (1) and a trinuclear compo und (AlMe2)(2)AlMe[CH3C(CH2NH)(CH2O)(CH2SPh)] (2), respectively. Both compounds were characterized by H-1 and C-13 NMR data, IR, and mass an d elemental analysis. Compound 1 was also characterized by single-crys tal X-ray diffraction analysis. Compound 1 crystallized in a tetragona l space group P4(1)2(1)2 (No. 92), with cell parameters a = 10.238(2) Angstrom, c = 24.470(2) Angstrom, V = 2565(1) Angstrom(3), Z = 4, and R = 0.060. It appears that the central aluminum atom is surrounded by two tripodal ligands in an octahedral geometry, whereas the other thre e aluminum atoms act to bridge the two ligands. Compound 2 has a penta coordinated aluminum center surrounded by two tripodal ligands and one methyl group. The sulfur atoms on the tripodal ligand were not coordi nated to the central aluminum atom.