N,O versus O,O coordination in β-imino diketonato complexes: Role of the metal center and of the imino substituent
摘要:
beta-Imino carbonyl enolato metal(II) complexes of general formula [M((RCO)(R'CO)CC(R '') NH)(2)] (M = Mn, Fe, Co, Ni, Cu, Zn, Pd, R = R' = Me, R '' = CCl(3); M = Cu, Pd, R = R' = Me, R '' = PhCO; R = Me, R' = Ph, R '' = PhCO; R = R' = Ph, R '' = PhCO) are easily synthesized by the reaction of metal(II) acetates with the proper beta-enaminodiones in 1/2 molar ratio in ethanol at room temperature. In all the cases the trifunctional NOO beta-imino carbonyl enolate ligand acts as bidentate to give ML(2) complexes, whose structure depends on the metal center and on the nature of the substituent R '' at the imino carbon. With R '' = CCl(3) an O,O coordination is observed for all the metal centers but one, in fact palladium(II) exhibits an N,O coordination through the imino nitrogen and one keto oxygen. By contrast with R '' = PhCO the ligand is always coordinated through the imino nitrogen and one keto oxygen atom. (C) 2008 Elsevier B. V. All rights reserved.
Veronese, Augusto C.; Callegari, Rosella; Basato, Marino, Journal of the Chemical Society. Perkin transactions I, 1994, # 13, p. 1779 - 1786
作者:Veronese, Augusto C.、Callegari, Rosella、Basato, Marino、Valle, Giovanni
DOI:——
日期:——
Carbon-carbon bond formation in the reaction of benzoyl cyanide with nickel(<scp>II</scp>)β-diketonates
作者:Marino Basato、Umberto Casellato、Rodolfo Graziani、Augusto C. Veronese
DOI:10.1039/dt9920001193
日期:——
Nickel beta-diketonates react with benzoyl cyanide to give C-C bond formation between the methine and the cyano carbon atoms. The resulting reddish compounds are square-planar iminodiketonato complexes, which are likely catalytic intermediates in the synthesis of beta-enaminodiones from beta-diketones and PhCOCN. The acetylacetonato derivative [Ni(acac.PhCOCN)2] can be obtained in the solid state in two stable forms; an X-ray single-crystal analysis of form II indicates that the unit cell [monoclinic, space group P2(1)/c, a = 11.408(5) angstrom, b = 15.109(4) angstrom, c = 14.515(5) angstrom, beta = 108.93(3)-degrees] contains two couples of independent, structurally very similar, molecules of the complex. The nickel atom is always centrosymmetrically co-ordinated to the ligand in a N,O bonding configuration, which is preferred to the alternative O,O one.
BASATO, M.;CORAIN, B.;COFLER, M.;VERONESE, A. C.;ZANOTTI, G., J. CHEM. SOC. CHEM. COMMUN., 1984, N 23, 1593-1594
作者:BASATO, M.、CORAIN, B.、COFLER, M.、VERONESE, A. C.、ZANOTTI, G.