A. P. Klyagina

On the nature of the chemical bond in heterobimetallic palladium(II) complexes with divalent 3d metals

The complex Pd(μ-OOCMe)4Cu(OH2) · 2Pd3(μ-OOCMe)6 was synthesized and characterized by X-ray crystallography. In the heterometallic moiety of this complex, the PdII and CuII atoms are at an extraordinary short distance (2.521(3) Å). DFT quantum-chemical calculations of the geometric and electronic structure of a series of heterobinuclear paddlewheel complexes PdIIMII(μ-OOCMe)4L (M = ZnII, NiII, CuII, CoII, FeII; L = OH2 and NCH) and their formate analogues PdIIMII(μ-OOCH)4L (M = ZnII, NiII, FeII) showed that the extraordinary short Pd⋯M distance in all these complexes is caused only by the tightening effect of carboxylate bridges rather than by the metal-metal bond. The direct Pd-M interaction becomes possible only after removal of electrons from the antibonding orbitals and formation of oxidized complexes of the [PdIII(μ-OOCMe)4NiIII]2+ type.

Chiroptical properties of heterotrimetallic ‘wing-tip’ butterflies; synthesis and crystal structure of (μ-H)Ru2Fe2PdC(CO)12 (η3-ß-C10H15)

Abstract HRu2Fe2PdC(CO)12 (η3-s-C10H15) cluster was prepared in the reaction of (Et4N) [HFe2Ru2C(CO)12] with [Pd(η3-s-C10H15)Cl]2. X-ray structural study of HRu2Fe2PdC(CO)12 (η3-s-C10H15) (where s-C10H15 is s-pinenyl) revealed a wing-tip butterfly geometry of the metal core and (1R, 2S, 3S, 5R) absolute configuration for both crystallography independent molecules in the crystal. Chiroptical properties of this cluster are compared with other clusters containing a Pd(η3-s-C10H15) fragment and discussed.

Platinum acetate blue: synthesis and characterization.

Platinum acetate blue (PAB) of the empirical formula Pt(OOCMe)2.5±0.25, a byproduct in the synthesis of crystalline platinum(II) acetate Pt4(OOCMe)8, is an X-ray amorphous substance containing platinum in the oxidation state between (II) and (III). Typical PAB samples were studied with X-ray diffraction, differential thermal analysis-thermogravimetric, extended X-ray absorption fine structure, scanning electron microscopy, transmission electron microscopy, magnetochemistry, and combined quantum chemical density functional theory-molecular mechanics modeling to reveal the main structural features of the PAB molecular building blocks. The applicability of PAB to the synthesis of platinum complexes was demonstrated by the preparation of the new homo- and heteronuclear complexes Pt(II)(dipy)(OOCMe)2 (1), Pt(II)(μ-OOCMe)4Co(II)(OH2) (2), and Pt(III)2(OOCMe)4(O3SPhMe)2 (3) with the use of PAB as starting material.

Heterometallic Palladium(II)–Indium(III) and −Gallium(III) Acetate-Bridged Complexes: Synthesis, Structure, and Catalytic Performance in Homogeneous Alkyne and Alkene Hydrogenation

The reaction of Pd3(OOCMe)6 with indium(III) and gallium(III) acetates was studied to prepare new PdII-based heterometallic carboxylate complexes with group 13 metals. The heterometallic palladium(II)-indium(III) acetate-bridged complexes Pd(OOCMe)4In(OOCMe) (1) and Pd(OOCMe)4In(OOCMe)·MeCOOH (1a) were synthesized and structurally characterized with X-ray crystallography and extended X-ray absorption fine structure in the solid state and solution. A similar Pd-Ga heterometallic complex formed by the reaction of Pd3(OOCMe)6 with gallium(III) acetate in a dilute acetic acid solution, as evidenced by atmospheric pressure chemical ionization mass and UV-vis spectrometry, was unstable at higher concentrations and in the solid state. Complex 1 catalyzes the liquid-phase-selective phenylacetylene and styrene hydrogenation (1 atm of H2 at 20 °C) in acetic acid, ethyl acetate, and N, N-dimethylformamide solutions, while no Pd metal was formed until alkyne and alkene hydrogenation ceased.

Unusual sandwich platinum(II) complex: [Pt(phen)2]2+ cation between two Pt(phen)(OOCMe)2 molecules

New carboxylate platinum(II) complexes: syn and anti isomers of Pt(phen)(OOCMe)2 molecular complex, [Pt(phen)(NCMe)2](O3SCF3)2, as well as unusual sandwich complex [Pt(phen)2]2+ · 2syn-[Pt(phen)(OOCMe)2] where [Pt(phen)2]2+ cation is inserted between two syn-Pt(phen)(OOCMe)2 molecules were synthesized and structurally characterized by X-ray diffraction analysis. As distinct from syn- and anti-Pt(phen)(OOCMe)2 and [Pt(phen)(NCMe)2](O3SCF3)2 complexes with flat phenanthroline ligand, the phen ligands in [Pt(phen)2]2+ cation have a curved configuration. Comparative DFT analysis of geometry of model structures phen, phen+, phenH+, and [Ptphen2]n+ (n = 1, 2) showed that electron removal from phen molecule had no effect on its geometry in both free state and platinum(II) complexes.