Three new di-metallorganic cobalt complexes of the type trans-(Bz)(2)Co(chel), where Bz is a benzyl group sigma-bonded to cobalt atom and chel is an equatorial chelating system constituted by an amino-oximic ligand and its conjugated base, were synthesised. The protonated and the unprotonated ligands interact through an O-(HO)-O-... bridge stabilising the entire structure. The complexes differ in the equatorial moiety which is derived from the following ligands: HLN-py = 3-[2-pyridyl)ethylimino]-butan-2-one oxime), HLN-Ph = 3-[(2-phenyl)ethylimino]-butan-2-one oxime and the analogous HLN-PhCl = 3-[2-chlorophenyl)ethylimino]-butan-2-one oxime. Two of these compounds, namely those derived from HLN-py and HLN-PhCl were structurally characterised by means X-ray diffractometry. Data reveal that each complex is characterised by the presence of two unusually long cobalt-carbon bonds which are 2.120(4) Angstrom (mean value) in complex with HLN-py ligand and 2.119(4) Angstrom (mean value) in complex with HLN-PhCl. These data are consistent with a strong mutual trans-influence exerted by one ligand on the other. (C) 2003 Elsevier B.V. All rights reserved.
Three new di-metallorganic cobalt complexes of the type trans-(Bz)(2)Co(chel), where Bz is a benzyl group sigma-bonded to cobalt atom and chel is an equatorial chelating system constituted by an amino-oximic ligand and its conjugated base, were synthesised. The protonated and the unprotonated ligands interact through an O-(HO)-O-... bridge stabilising the entire structure. The complexes differ in the equatorial moiety which is derived from the following ligands: HLN-py = 3-[2-pyridyl)ethylimino]-butan-2-one oxime), HLN-Ph = 3-[(2-phenyl)ethylimino]-butan-2-one oxime and the analogous HLN-PhCl = 3-[2-chlorophenyl)ethylimino]-butan-2-one oxime. Two of these compounds, namely those derived from HLN-py and HLN-PhCl were structurally characterised by means X-ray diffractometry. Data reveal that each complex is characterised by the presence of two unusually long cobalt-carbon bonds which are 2.120(4) Angstrom (mean value) in complex with HLN-py ligand and 2.119(4) Angstrom (mean value) in complex with HLN-PhCl. These data are consistent with a strong mutual trans-influence exerted by one ligand on the other. (C) 2003 Elsevier B.V. All rights reserved.