Acetylacetone coordination complexes with

The horon difluoride coordination complex is decomposed by heating under reflux with an aqueous solution of 2 mols of sodium acetate per mol of anhydride, whereupon the p diketone (acetylacetone) is liberated. 

Gallium (I). Hahdes of Ga(I) ate known only in the vapor phase. Coordination complexes of GaCl and GaBt have been obtained with dioxane, morpholine, and acetylacetone. 

The chloride ligand in OsHCl(CO)(P,Pr3)2 can be also replaced by acetate, acetylacetonate, or iodide (Scheme 49). The reactions with the O-donor ligands lead to six-coordinate complexes OsH(K2-02CMe)(CO)(P, Pr3)2 and OsH(acac) (CO)(P Pr3)2,12 respectively, whereas the treatment of OsHCl(CO)(FPr3)2 with Lil affords the five-coordinate derivative Osffl(CO)(P, Pr3)2.67 Complex OsH... 

ATdc values for the lanthanide acetylacetonates are the reverse from that expected for the size effect. The explanation is hkely that the neutral complex with the formula LnAs is coordinatively unsaturated, which means that a hydrated complex exists in the aqueous phase (possibly also in the organic phase). The more coordinatively unsaturated lanthanide complexes (of the larger ions) can accommodate more water and thus are more hydrophilic. The result is a A dc several orders of magnimde lower for the lightest. La, than for the heaviest, Lu. 

Several polydentate SBs may act as binucleating ligands see Section 33.5.12.1. Only a few miscellaneous polydentate SBs will be included here. A complex with the SB obtained in the reaction of two moles of benzoyl hydrazide with acetylacetone had v(V=0) = 995 cm 1, Pea =1.7BM and was monomeric square pyramidal (117).792 A few complexes with the ethylenediamine derivatives of 2,2 -dihydroxychalcones (118) were prepared in ethanol.793 The stoichiometry is 1 1 and the atoms involved in the coordination were two deprotonated oxygens and two nitrogen atoms. v(V—O) (970-985 cm-1) and f4 (1.73-1.83 BM) suggest a monomer however, molecular weights in nitrobenzene suggest a dimer. 

The methine proton in the keto form and the hydroxyl proton in the enol form of jS-diketones are acidic and their removal generates 1,3-diketonate anions (2), which are the source of an extremely broad class of coordination compounds referred to generically as diketonates or acetylacetonates. The synthesis, structure and properties of these compounds form the focus of this chapter. Di-ketonate anions are powerful chelating species and form complexes with virtually every transition and main group element. The scope of this chemistry is very large and it has been assessed earlier in several excellent reviews.9-14... 

Hydrolysis of Pd(MeCOCHMe)2 in aqueous methanol is considered to involve Pd(0,0-MeCOCHCOMe)(0-MeCOCHCOMe)(MeOH) as an intermediate from which the monodentate acetylacetonate ligand is then solvolyzed.221 Subsequent studies on Lewis base complexes of palladium bis(diketonate) complexes provide ample support for the proposed intermediate. A pulse radiolysis study of the kinetics of aquation of M(MeCOCHCOMe) " (M = Cr, Co) indicates that an 17,-172 equilibrium involving one or more of the acetylacetonate ligands occurs, associated with an acid-catalyzed removal of the monodentate ligand.222 Treatment of Cu(MeCOCHCOMe)2 with picric acid in moist dichloromethane affords a partially hydrolyzed material, Cu(MeCOCHC-0Me)(H20)2[C6H2(N02)30], proposed to contain square pyramidal five-coordinate copper with the oxygen atom from the picrate moiety at the apex.223... 

Molybdenum trioxide, intercalation into, 12, 823 Molybdocenes, as anticancer agents, 1, 892 MOMNs, see Metal-organometallic coordination networks Monisocyanides, with silver(I) complexes, 2, 223 Monitoring methods, kinetic studies, 1, 513 Mono(acetylacetonate) complexes, with Ru and Os halfsandwich rf-arenes, 6, 523 tj2-Monoalkene monodentate ligands, with platinum divalent derivatives, 8, 617 tetravalent derivatives, 8, 625 theoretical studies, 8, 625 zerovalent derivatives, 8, 612... 

Unlike Si and Ge acetylacetonates (acac), in which the central M atom is hexacoordinated, the coordination number of the Sn atom in RSn(acac)3 is 7173. Hexacoordinated Si, Ge, Sn, Pb complexes with tropolone (Tp) are known. Tp4M molecules, where the metal atom is octacoordinated for M = Sn, Pb or hexacoordinated for M = Si, Ge, are of particular interest. The latter compounds correspond to the structure Tp3M+Tp- and exist as salts or ion pairs174. 

Both di- and trimerization of butadiene with soluble nickel catalysts are well-established homogeneous catalytic reactions. The precatalyst having nickel in the zero oxidation state may be generated in many ways. Reduction of a Ni2+ salt or a coordination complex such as Ni(acac)2 (acac = acetylacetonate) with alkyl aluminum reagent in the presence of butadiene and a suitable tertiary phosphine is the preferred method. The nature of the phosphine ligand plays an important role in determining both the activity and selectivity of the catalytic... 

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