Anchoring selenido-carbonyl ruthenium clusters to functionalised silica xerogels

Silica Xerogels containing carbonyl Ru3Se2 nido clusters were prepared in three different ways. The simple dispersion of [Ru3(mu3-Se)2(CO)7(PPh 3)2] via sol gel process produces an inhomogeneous material; by contrast, homogeneous xerogels were obtained by reaction of [Ru3(mu3-Se)2(CO)8(PPh 3)] with functionalised xerogels containing grafted diphenylphosphine moieties and by reaction of [Ru3(CO)12] with a xerogel containing grafted phosphine-selenide groups. The reaction between [Ru3(CO)12] and dodecyldiphenylphosphine selenide led to the formation of four selenido carbonyl clusters, which are soluble in hydrocarbon solvents and can be deposited as thin films from their solution by slow evaporation. Xerogéis de silica contendo carbonilas metálicas polinucleares (clusters) com estrutura nido Ru3Se2 foram preparadas através de três rotas diferentes. A simples dispersão do cluster [Ru3(mi3-Se)2(CO)7(PPh 3)2] pelo processo sol gel produz um material não homogêneo. Xerogéis homogêneos foram obtidos através da reação de [Ru3(mi3-Se)2(CO)8(PPh 3)] com xerogéis funcionalizados contendo fragmentos difenilfosfino enxertados, e pela reação do [Ru3(CO)12] com um xerogel contendo grupos fosfinoseleneto enxertados. A reação entre [Ru3(CO)12] e seleneto de dodecildifenilfosfinoseleneto resultou na formação de quatro clusters contendo ligantes carbonil e seleneto, solúveis em solventes apolares e que podem ser empregados na confecção de filmes

Struttura cristallina della catena di μ \mu \ -(oftalato)cuprato(II) di dirubidio diidrato

The crystal structure of dirubidium catena-di- $\mu \$ (ophthalato)cuprate(II) dihydrate has been determined by an X-ray analysis. The structure was solved by Patterson and Fourier methods and refined by block-diagonal least-squares (final R = 6,6%). The structure consists of nearly planar-square complexes formed by four oxygen atoms belonging to four phthalate ions. Each phthalate ion bridges two copper atoms, so the coordination polyhedra are Joined together in chains parallel to [001]

Formation of diiridium(II) complexes by photoassisted oxidative-addition reactions: Structure of a stable binuclear iodo(iodomethyl)iridium(II) complex

The diiridium(II) complexes 2 (X = CH3, CH2I) are not intermediates of alkylidene-bridged complexes but are stable compounds. The notable acceleration of the synthesis 1 → 2 by light suggests a radical mechanism, but the formation of a mixture of chloro-, bromo- and iodocomplexes in the synthesis with CH2I2 in the presence of [Bu4N]Br and CH2Cl2 is quite contradictory thereto.Peer reviewe

Thiocarbonylrhodium complexes with pyrazolate-type ligands

The first binuclear thiocarbonylrhodium complexes of formula [Rh(μ-L)(CS) (PPh3)]2 (L = pyrazolate type ligand) have been prepared. The crystal structure of the complex with L = 3,5-dimethylpyrazolate has been determined by X-ray diffractometry. Other related mononuclear thiocarbonyl derivatives are also described.Peer reviewe

Heterotrinuclear angular aggregates of rhodium, iridium, palladium and Group 11 metals. X-Ray structure of the complex [(cod)2Rh2(µ3-C7H4NS2)2Ag(O2ClO2)](cod = cycloocta-1,5-diene)

The binuclear complexes [{Ir(µ-C7H4NS2)(cod)}2]1(cod = cycloocta-1,5-diene) and [{Pd(µ-C7H4NS2)(η3-C3H5)}2]2 are isolated from the reaction of the chloro-bridged compounds [{M(µ-Cl)L2}2](M = Ir, L2= cod; M = Pd, L2= allyl) and lithium benzothiazole-2-thiolate. Reactions of 1 and 2 with the appropriate species [ML2(Me2CO)2]+ afford the homotrinuclear angular aggregates [M3(µ3-C7H4NS2)2(L2)3]+. Starting from [{Rh(µ-C7H4NS2)(CO)(PPh3)}2] and [{M′(µ-C7H4NS2)(cod)}2](M′= Rh or Ir), this method is highly useful to prepare the heterotrinuclear aggregates [(Ph3P)2(OC)2Rh2(µ3-C7H4NS2)2ML2]+[ML2= Ir(cod) or Pd(allyl)], [(cod)2M′2(µ3-C7H4NS2)2AgX]n+(n= 0, X = ClO4, Cl, NO3 or BF4; n= 1, X = PPh3 or pyridine) and [(cod)2M′2(µ3-C7H4NS2)2M″Cl](M″= Cu or Au). They have been characterized by 1H, 31P NMR and IR spectroscopy and [(cod)2Rh2(µ3-C7H4NS2)2Ag(O2ClO2)]8 by X-ray diffraction methods. Crystals of 8 are orthorhombic, space group Pbcn, with a= 7.635(5), b= 27.564(11), c= 15.564(8)Å, Z= 4. The structure has been solved from diffractometer data by direct and Fourier methods and refined by full-matrix least squares to R= 0.062 for 1863 observed reflections. The complex, having an imposed C2 symmetry, shows two Rh and one Ag atoms in a bent arrangement with two molecules of benzothiazole-2-thiolate interacting with all three metals. Each ligand is bonded to one Rh atom through the nitrogen and asymmetrically bridges one Rh and one Ag atom through the sulphur. The Rh atoms complete their co-ordination with a cod ligand interacting through the two olefinic bonds, while the Ag atom completes the co-ordination with two oxygen atoms from a perchlorate anion, which has been found disordered and distributed in two positions of equal occupancy factor with three oxygen atoms in common.We thank the Direccion General de Investigacion Cientifica y Tecnica (D.G.I.C.Y.T.) (Project PB88-0056) and Consejo Superior de Investigaciones Cientificas (C.S.I.C.) for financial support and Diputacion General de Aragon for a fellowship (to J. J. P.-T.)Peer reviewe

Nucleophylic attack of amine and hidroxide to platinum-dichlorobenzonitrile. Crystal structure of [Pt(NH=CPhNButCH2CH2NHBut)Cl(NHCOPh)], 2, and cis [Pt(NH=CPhNButCH2CH2NHBut)Cl2(NCPh)], 3

The trans and cis isomers of [PtCl2(NCPh)2] react with N,N′-di-tert-butylethylenediamine (t-Bu2en) under normal conditions to give [Pt(NH=CPhN-t-BuCH2CH2NH-t-Bu)Cl(NCPh)]Cl (1) and cis-[Pt(NH=CPhN-t-BuCH2CH2NH-t-Bu)Cl2(NCPh)] (3), respectively. In both cases one end of t-Bu2en adds to benzonitrile forming an amino-amidine ligand which is chelated in 1 (forming a seven-membered metallacycle) and monocoordinated in 3. The residual benzonitrile in the cationic complex 1 readily reacts with base to give a benzamidate species, [Pt(NH=CPhN-t-BuCH2CH2NH-t-Bu)Cl-(NHCOPh)] (2). Compound 3 exhibits, in solution, isomerization about the azomethine double bond (Δ‡223 = 10.8 ± 0.3 kcal mol-1) and more slowly undergoes an internal rearrangement with substitution of the residual benzonitrile by the uncoordinate end of the diamine and formation of [Pt(NH=CPhN-t-BuCH2CH2NH-t-Bu)Cl2] (4). The structures of 2 and 3 have been solved by single-crystal diffraction. Compound 2 crystallizes as methanol solvate (1:1) in the monoclinic space group P21/n with a = 25.374 (13) Å, b = 11.351 (8) Å, c = 9.338 (5) Å, β = 92.03 (4)°, and Z = 4. Compound 3 crystallizes as toluene solvate (2:1) in the monoclinic space group P21/a with a = 18.090 (10) Å, b = 9.376 (4) Å, c = 17.297 (7) Å, β = 91.76 (4)°, and Z = 4. Both compounds contain a strong intramolecular hydrogen bond which involves the oxygen atom of the benzamidate anion and the cis amine group of the chelate amino-amidine ligand in 2, the free and coordinate ends of the monocoordinate amino-amidine ligand, so forming a pseudo-seven-membered ring, in