Synthesis, structure and spectroscopic behaviors of a five- and six-coordinated tri-cobalt(II) cluster: [(CoL)2(OAc)2Co].2C2H5OH.
A tri-nuclear cobalt(II) cluster, [(CoL)2(OAc)2Co].2C2H5OH, has been synthesized by the reaction of cobalt(II) acetate tetrahydrate with a novel Salen-type bisoxime chelating ligand, 3,3'-dimethoxy-2,2'-[ethylenedioxybis(nitrilomethylidyne)]diphenol (H2L), and characterized by elemental analyses, IR spectra, TG-DTA and molar conductances. UV-vis spectroscopic titration in methanol solution clearly indicated the exclusive formation of the 3:2 [Co3L2]2+ cluster. The single-crystal X-ray diffraction determination of the Co(II) cluster shows that there are two acetate ions coordinate to three cobalt(II) ions through Co-O-C-O-Co bridges, and quadruple mu-phenoxo oxygen atoms from two [CoL] chelates also coordinate to cobalt(II) ions. Interestingly, different conformational central ions: five- and six-coordinated geometries were found in the cluster.
Dong
Wen-Kui
WK
School of Chemical and Biological Engineering, Lanzhou Jiaotong University, Anning West Road 88, Lanzhou 730070, Gansu, China. dongwk@mail.lzjtu.cn
Li
Li
L
Li
Cong-Fen
CF
Xu
Li
L
Duan
Jin-Gui
JG
D000096:Acetone / Q000737:chemistry*; D003035:Cobalt / Q000737:chemistry*; D018360:Crystallography, X-Ray; D000431:Ethanol / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D013053:Spectrophotometry; D013696:Temperature; D017186:Titrimetry
D000096:Acetone; D003035:Cobalt; D000431:Ethanol