N-Oxide-bridged complexes of cobalt(II) and nickel(II) with 2-acetylpyridine 1-oxide oxime (pro). X-ray crystal structure of the dimeric complex [Co(pxo)(CH3OH)Cl2]2
作者:Godfrey C. Chiumia、David J. Phillips、A. David Rae
DOI:10.1016/0020-1693(95)04707-g
日期:1995.10
The X-ray structure is reported for the dimeric complex [Co(pxo)(CH3OH)Cl-2](2) involving the bidentate N-oxide ligand 2-acetylpyridine 1-oxide oxime (pxo). The complex is monoclinic, C2/c, a=19.328(6), b=9.810(4), c=15.561(6) Angstrom, beta=126.94(2)degrees, Z=4. The centrosymmetric dimer is N-oxide-bridged. Each cobalt has a six-coordinate NO3Cl2 environment, produced by O,N coordination from one pxo, bridging N-oxide bonding from a second pro, terminal chlorides, and coordinated CH3OH. Attempted preparations of other 1:1 pro complexes, using a range of solvents, generally yielded some previously reported 2:1 complexes of the type M(pxo)(2)X(2). However, the complexes Ni(pxo)Cl-2 . H2O and Co(pxo)Cl-2 were also obtained, and, on the basis of magnetic, spectroscopic and X-ray powder diffraction measurements, the complexes appear to have six-coordinate structures, involving chloride-bridged chains of N-oxide-bridged dimer molecules.