The 4-(dipyridylamino)benzoylpyridine ligand as a supramolecular synthon. Solid state organization of a bis(bipyridyl)ruthenium(II) complex
作者:Daniel L. Reger、James R. Gardinier、Mark D. Smith
DOI:10.1016/s0020-1693(03)00135-x
日期:2003.8
The bis(2,2'-bipyridyl)ruthenium(II) derivative [Ru(bPY)(2)(p-py(2)N(C6H4)C(O)PY)][PF6](2) was prepared by reaction between '[Ru(bpy)(2)(EtOH)(2)][PF6](2)' and an excess of p-py(2)N(C6H4)C(O)(py). X-ray analysis shows that the ruthenium is coordinated via the N,O ligand set rather than the via the N,N'-dipyridylamino fragment. The cations are arranged in dimeric units as a result of (C)H...N weak hydrogen bonding interactions. The dimeric units are further organized into a supramolecular chain structure of cations by pi-pi stackina interactions involving bipyridyl ligands and by weak CH...O interactions. The complicated H-1 and C-13 NMR spectra were completely assigned by using two-dimensional methods. The optical spectra in CH3CN show two high-energy ligand-based absorption maxima that show a small bathochromic shift when compared to the spectral data of the free arylpyridylmethanone ligand and two long-wavelength absorption maxima centered near 440 and 574 nm that are assigned to Ru(dpi)-pi*(py) and Ru(dpi)-pi*[ArC(O)(py)] MLCT transitions, respectively. The cyclic voltammogram shows an irreversible oxidation wave for the Ru(II)/(III) couple at + 1.31 V versus SCE. (C) 2003 Elsevier B.V. All rights reserved.