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Abstract: Fast oxidations of the iron(II) N,N-dialkylcarbamato complexes [Fe(II)(O2CNR2)2] n (R=Et, n =6, 1; R= i Pr, 2) and [Fe(II)8(μ4-O)2(O2CNiPr2)12], 3, by dioxygen were carried out both in an anhydrous hydrocarbon and in the solid state affording [Fe(III)2(O)(O2CNR2)4] x , 7 and 8 for R=Et and i Pr, respectively, and [Fe(III)4(O)3(O2CNiPr2)6] y , 9. The stoichiometric O2 uptake was not accompanied by oxidation of the ligand. Recovery of unchanged starting material was observed when the manganese(II) derivatives [Mn(II)(O2CNR2)2] n (R=Et, n =6, 4; R= i Pr, 5) were treated with O2. Nevertheless, when [Mn(II)8(μ4-O)2(O2CNiPr2)12], 6, prepared in situ by reaction of 5 with water (Mn/H2O molar ratio=4), was reacted with O2, complete oxidation occurred to a product where manganese showed an average oxidation number III, [Mn(III)4(O)3(O2CN i Pr2)6] y , 10. The product [Mn(II)6Mn(III)2(μ4-O)2(μ3-O)(O2CN i Pr2)12], 11, obtained by partial oxidation of 6 by O2, has been characterised by X-ray diffraction methods. [Copyright &y& Elsevier]

The simple but rarely used heterotopic divergent ligand N-oxide-4,4′-bipyridine (bipyMO) has been exploited, for the first time, for the preparation of heterometallic derivatives, showing the ability to selectively use its two potential coordination sites in dependence of the metal ion nature. By reacting in refluxing acetonitrile ∞ 1 [Cu(hfac) 2 (bipyMO)] with ∞ 1 [Mn(hfac) 2 (bipyMO)] (herein completely characterized), the heterometallic self-assembled monodimensional coordination polymer containing the two regularly alternated moieties Cu(hfac) 2 [N] 2 and Mn(hfac) 2 [O] 2 was obtained in high yield and purity and structurally characterized. On the other hand, a molecular heterometallic compound was obtained using, as a ligand, the here prepared mononuclear complex trans -[PtCl 2 (bipyMO)(PPh 3 )], with the hypodentate bipyMO ligand coordinated to platinum through the nitrogen atom. Reaction with [Zn(hfac) 2 (DME)] afforded the heterometallic trinuclear complex trans [Zn(hfac) 2 { trans -PtCl 2 (PPh 3 )(bipyMO)} 2 ] that was structurally characterized. [ABSTRACT FROM AUTHOR]

Exhaustive hydrolysis of a mixture of [La 4 (CO 3 )(O 2 CNBu 2 ) 10 ] and [Cu(O 2 CNBu 2 )(py ∗ ) 2 ] (py ∗ = 4-dimethylamino pyridine) in molar ratio 1/2 corresponding to a La/Cu molar ratio 2/1 was carried out in toluene at room temperature. The carbamato derivatives of lanthanum and copper can be easily prepared by extraction of the metal ions from aqueous solution into heptane by the NHBu 2 /CO 2 system, according to a method previously reported. The copper precursor was selected amongst a number of derivatives in respect of its easy tractability. The tetragonal modification T′ of La 2 CuO 4 was obtained by treatment at 600 °C of the intermediate mixed carbonate. The thermal treatment of T′-La 2 CuO 4 at 850 °C, followed by cooling down to room temperature, afforded the orthorhombic modification of the mixed oxide. [ABSTRACT FROM AUTHOR]

Nanostructured ceria has been prepared in mild conditions by hydrolysis of the N , N -dibutylcarbamato complex of cerium(III), [Ce(O 2 CNBu 2 ) 3 ], obtained by lanthanide extraction from aqueous solution into heptane containing CO 2 saturated NHBu 2 . In dependence of the hydrolysis conditions, cerium(III) carbonates or hydroxocarbonate (characterized by IR, XRD and metal content) were obtained. Thermal treatment of these products at relatively low temperature (200 °C) yielded CeO 2 in the form of a light yellow powder. The structure and morphology of the samples were studied by TEM, FESEM and XRD studies. The medium crystallite dimensions, estimated by TEM, appear to be of a few nanometers. Ceria with smaller medium crystallite dimensions was obtained by increasing the amine concentration in the course of the hydrolysis process. [ABSTRACT FROM AUTHOR]