Tetranuclear Palladium Research Articles

Synthesis and crystal structure of dinuclear and tetranuclear palladium dppm complexes. [Pd 2( μ-dppm) 2(vpy)Cl] and [Pd 4( μ-dppm) 4 ( μ-X) 2](ClO 4) 2 (X = Cl, Br and I)

Reaction of the intermediate [Pd 2( μ-dppm) 2] 2 which was prepared from [Pd 2( μ-dppm) 2X 2] (X = Cl, Br and I) and AgClO 4 in ethanol with 2-vinylpyridine (vpy) afforded dinuclear Pd(I) dppm complex [Pd 2( μ-dppm) 2(vpy)Cl] (1). When the intermediate [Pd 2( μ-dppm) 2] 2 was allowed to stand for a few days, tetranuclear Pd dppm complex [Pd 4 ( μ-dppm) 4( μ-X) 2](ClO 4) 2 (X = Cl (2), Br (3) and I (4)) was systematically formed. The structure for 1 and 2 were crystallographically determined. On complex 1 two Pd atoms are doubly bridged by two dppm ligands to form an eight-membered Pd 2P 4C 2 framework in a twist-chair conformation. Each Pd atoms is also coordinated by the Cl atom and the N atom of vpy in unsymmetrical side-by-side mode. The Pd–Pd distance is 2.597(2) Å and the torsion angle between two Pd 2P 2 plane is 43.2°. On the other hand four Pd atoms on 2 are bridged by four dppm ligands to form a rectangular Pd 4 core, which is composed of the shorter Pd–Pd separations (2.590(1) Å) and the close Pd · · · Pd separations (3.818(2) Å). The later Pd · · · Pd separation is also bridged by the Cl atom. The Pd–P distance (2.351(1) Å) bridging the close Pd · · · Pd separation is rather longer than that (2.238(2) Å) bridging the shorter Pd–Pd separation.

An unusual cyanide-bridged extended A-frame complex: the molecular structure of [Pd 2Br 2(μ-PPh 2)(μ-dppm) 2(μ-CN) 2

The tetranuclear palladium complex [Pg 2Br 2(μ-PPh 2)(μ-dppm) 2(μ-CN) 2] was isolated by slow crystallization of an acetone solution, and its solid state structure has been determined by X-ray crystallography. The molecule is composed of two dppm-bridged dipalladium moieties held together by two cyano ligands. It adopts an extended or double A-frame structure, with the additional bridging PPh 2 groups occupying sites on opposite faces of the Pd 4 unit.

Synthesis and X-ray Crystallographic Characterization of (μ-(Diphenylphosphino)phenyl-C2,P)palladium Bromide. A Novel Tetranuclear Metalated Compound

The synthesis and crystal structure of a tetranuclear palladium cluster, [Pd(PC)Br]4 (PC) = [P(C6H4)Ph2]-), is described. Cleavage of this cluster with phosphines yields the mononuclear species Pd(PC)Br(P) in the form of cis and trans isomers. An equilibrium between mono- and tetranuclear species is observed for P = PCBr.

Reactions of palladium(I) carbonylacetate cluster with alcohols

Reactions of a tetranuclear palladium cluster [Pd(CO)(OAc)[4 with C1-C3 alcohols have been found to proceed simultaneously via several routes to form CO, and dialkyl carbonates, the products of oxidation of coordinated CO ligands, along with carbonyl compounds which form due to oxidation of the corresponding alcohols. Alkoxy, alkoxycarbonyl, and acyl palladium derivatives are shown to be the intermediates of the reactions studied.

Three-Dimensional H-Bonded Networks Based on Mono- and Tetranuclear Metal-Pteridine Complexes

Abstract The crystal structure of the transition metal-pteridine complexes having three-dimensional hydrogen-bonded (H-bonded) network and stacking interactions between pteridine ligands are described; (1) Mononuclear copper(II)-pteridine complex and (2) Tetranuclear palladium(II)-pteridine complex.

A novel tetranuclear palladium(II) complex with 2-[(3-aminopropyl)amino]ethanethiol

A palladium(II) complex with 2-[(3-aminopropyl)amino]ethanethiol (HL), [Pd 4(L) 4]Cl 4 ( 1), has been synthesized and characterized by X-ray crystallography and NMR spectroscopy. The cation has a thiolate-bridged tetranuclear structure, in which each palladium ion is essentially coordinated by a square-planar N 2S 2 donor set.

Pd.H-C Interactions. Preparation and Structure of Orthometalated Tetranuclear Complexes of Palladium(II) and Platinum(II).

The reaction of 2-(1-naphthyl)benzothiazoline with palladium(II) acetate leads to helical mononuclear and orthometalated tetranuclear products. The molecular structures of mononuclear palladium(II) [Pd(H1-nabz)(2)] (1) (H(2)1-nabz = 2-N-(1-naphthylmethylideneamino)benzenethiolate), tetranuclear palladium(II) [Pd(4)(1-nabz)(4)] (2) and tetranuclear platinum(II) [Pt(4)(1-nabz)(4)] (3) have been determined by single-crystal X-ray diffraction method. Crystal data for complex 1 are as follows: a = 14.208(3) Å, b = 18.227(4) Å, c = 14.398(8) Å; beta = 94.55(3) degrees; V = 3717.0(23) Å(3); space group = P2(1)/n, Z = 4. Crystal data for the complex 2 are as follows: a = b = 15.798(3) Å, c = 23.728(4) Å; V = 5921.7(20) Å(3); space group = I4(1)/a, Z = 16 for the Pd(1-nabz) unit. Crystal data for the complex 3 are as follows: a = b = 15.496(2) Å, c = 24.348(3) Å; V = 5846.3(20) Å(3); space group = I4(1)/a, Z = 16 for the Pt(1-nabz) unit. The mononuclear palladium(II) complex reveals short ortho-hydrogen.palladium distances of 2.66(7) and 2.48(7) Å. These short distances and (1)H NMR studies provide a M.H-C interaction which can be regarded as a three-center four-electron interaction. The molecular structures of 2 and 3 confirm the formation of unusual tetranuclear compounds featuring a rare C,N,S-tridentate ligand derived from orthometalation of pendant side arm. The structural and chemical properties of the mononuclear palladium(II) complex 1 clearly suggest that 1 is a potential intermediate in the formation of the tetranuclear complex 2 by orthometalation reactions.

Synthesis and crystal structure of a tetranuclear bis (diphenylphosphino) methane palladium complex capped by a μ 4-bonded sulfide: [Pd 4(μ-dppm) 4(μ 4-S)]·4(CH 3) 2CO

We have prepared the tetranuclear palladium complex [Pd 4(μ-dppm) 4(μ 4-S)] ( 1) capped by a μ 4-bonded sulfide and crystallographically characterized it. Four Pd atoms are bridged by four dppm ligands to form the rectangular Pd 4 core, which are capped by the μ 4-bonded sulfide from the side above the Pd 4 plane. It was suggested that the μ 4-bonded S atom is derived from the cleavage of the CS bond of diethyldithio-carbamate. Complex 1 has the following crystal data: monoclinic, C2/c, a = 30.503(8), b = 12.061(2), c = 31.686(7) A ̊ , β = 118.25(2)°, V = 10268(8) A ̊ 3, Z = 4, R = 0.051, R w = 0.070 .

Di-, tri- and tetra-nuclear palladium(II) complexes with ureido bridging groups

The reaction of [Pd(hfac)2](Hhfac = hexafluoroacetylacetone) with ureas in MeOH gives di-, tri- and tetra-nuclear palladium(II) complexes with hfac chelates and ureido(1– or 2–) bridges.

Studies on interactions of isocyanide with transition metal complexes. 36. Synthesis and characterization of a binuclear palladium(I) complex with bridging .eta.3-indenyl ligands, Pd2(.mu.-.eta.3-indenyl)2(isocyanide)2, and its transformation to a tetranuclear palladium(I) cluster of isocyanides, Pd4(.mu.-acetate)4(.mu.-isocyanide)4

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStudies on interactions of isocyanide with transition metal complexes. 36. Synthesis and characterization of a binuclear palladium(I) complex with bridging .eta.3-indenyl ligands, Pd2(.mu.-.eta.3-indenyl)2(isocyanide)2, and its transformation to a tetranuclear palladium(I) cluster of isocyanides, Pd4(.mu.-acetate)4(.mu.-isocyanide)4Tomoaki Tanase, Takahito Nomura, Toshihiro Fukushima, Yasuhiro Yamamoto, and Kimiko KobayashiCite this: Inorg. Chem. 1993, 32, 21, 4578–4584Publication Date (Print):October 1, 1993Publication History Published online1 May 2002Published inissue 1 October 1993https://doi.org/10.1021/ic00073a019RIGHTS & PERMISSIONSArticle Views198Altmetric-Citations42LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (817 KB) Get e-AlertsSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts

Structure and reactivity of the cyclic tetranuclear palladium(II) complexes having o-phenylene, dialkyl sulfide and acetato as bridging ligands

A mixture containing palladium( II) acetate and dialkyl sulfide in a molar ratio of 1:2/3 is refluxed in benzene to afford yellow crystals [Pd 4(μ-C 6H 4) 2(μ-O 2CMe) 4(μ-SR 2) 2](SR 2=SPr 2 i ( 1), SPr 2 ( 2)). The X-ray diffraction analysis of 1 shows that 1 has a cyclic tetranuclear structure containing o-phenylene, diisopropyl sulfide and acetato as bridging ligands. Thermolysis of 1 gives triphenylene and the reaction of 1 with styrene yields 1,2- di[( E)-styryl]benzene. The formation process to 1 from palladium(II) acetate has been discussed.

Dinuclear and tandem tetranuclear palladium(II) complexes formed by oxidative addition of 2,6-bis(chloromethyl)-pyridine to [Pd(PPh3)4

2,6-Bis(chloromethyl)pyridine reacts with [Pd(PPh3)4] in toluene at 100 °C to afford two types of oxidative-addition products, Cα,N-bridging dinuclear and Cα,N,Cα′-bridging tandem tetranuclear palladium(II) complexes [{PdCl[C5H3(6-CH2Cl)N-2-CH2](PPh3)}2]1 and [{Pd2Cl2[C5H3N-2,6-(CH2)2]-(PPh3)2}2]2. When the reactant molar ratio was 1.3:1 the best yield (56%) of complex 1 was obtained, while that (39%) of complex 2 was also obtained using a 1:2 molar ratio. Complex 2 was also obtained in 48% yield by the reaction (1:2 molar ratio) between complex 1 and [Pd(PPh3)4]. With [Pt(PPh3)4], an analogous heteronuclear tetrametral complex was isolated. These were characterized by IR and NMR (1H, 13C and 31P) spectroscopy and mass spectrometry as well as elemental analysis and molecular weight determinations. Complex 2 reacts with excess NaBr and Ag(O2CR)(R = CH3 or CF3) to give the corresponding metathesis and substitution products respectively; diphosphines Ph2PCH2CH2PPh2 or cis-Ph2PCHCHPPh2 partially displace the triphenylphosphine ligands. On the other hand, Tl(acac)(acac = pentane-2,4-dionate) cleaves the tandem tetranuclear structure to afford a dinuclear palladium(II) complex.

Oxidation of bridging groups by carboxylate coordinated ligands in palladium clusters

Thermolysis of tetranuclear palladium clusters Pd4(μ-Q)4 Pd4(μ-Q)4(μ-O2CR)4 (Q=CPh2 or CO;R=Me, CMe3, Ph, CH2Cl or CF3) has been found to involve innersphere oxidation of carbene or carbonyl ligands during which an oxygen atom transfer occurs from the carboxylate group to the carbene or carbonyl ligand. The thermolysis of the carbonyl clusters gives rise to the products of CO2 insertion into the C–H bond of benzene or toluene used as solvents forming benzoic acid from benzene and a mixture of phenylacetic and toluic acids from toluene. The reaction of [Pd(OAc)2(PPh3)]2 with HCO2H includes the transfer of an O atom from formate ligand to the P atom and cleavage of the P-Ph bond accompanied by transfer of the Ph group from PPh3 ligand to the palladium atom. The structure of the complex formed, [Pd(μ-O2PPh2)(C6H5)(PPh3)]2, has been resolved by X-ray analysis.

Cyclometallated complexes of bis( N-benzylidene)-1,4-phenylenediamines. Synthesis and crystal structure of [1,4-{ [formula omitted]](Br)} 2C 6H 4] 2: a novel tetranuclear cyclometallated palladium(II) complex

Treatment of 1,4-{2,3,4-(MeO) 3C 6H 2C(H)=N-} 2C 6H, ( a) or 1,4-{4,5-(OCH 2O)C 6H 3C(H)=N-} 2-C 6H 4 ( b) with palladium(II) acetate gave the cyclometallated acetato-bridged complexes [1,4-{ Pd [2,3,4-(MeO) 3C 6HC(H)=N ](O 2CMe)} 2C 6H 4] n ( 1a) and [1,4- Pd[4,5-(OCH 2O)C 6H 2C(H)=N ](O 2CMe)} 2-C 6H 4] n ( 1b). These were converted into the analogous halide-bridged complexes by treatment with NaX ( 2a, 2b X = Cl; 3 a, 3b X = Br). Reaction of a or b with PdCl 2 also affords the chloro-bridged complexes 2a and 2b, which reacted with LiBr to give the bromo-bridged complexes 3a and 3b. The structure of 3a is described. This is the first example of a structurally characterized tetranuclear cyclometallated bromo-bridged palladium(II) complex. Crystals are triclinic, space group P 1 , with a 1109.1(4), b 1181.5(4), c 1481.5(5) pm, α 77.33(3), β 80.04(3), γ 82.50(3), U 1.857(1) nm 3, Z = 1, R = 0.0558 and R W = 0.0610, for 3871 independent reflections with I > 2.0σ-( I). The structure is a centrosymmetric tetranuclear palladium(II) dimer with symmetrically bridging bromine atoms and non-bonding Pd ⋯ Pd distance of 366.2(5) pm.

Thermolysis of Tetranuclear Palladium Clusters: Unexpected Transfer of Oxygen from a Carboxylate Group to Carbene and Carbonyl Bridging Ligands; Carbon Dioxide Insertion into C [sbnd]H Bonds

Thermolysis of the tetranuclear palladium clusters [Pd4(μ-Q)4(μ-O2CR)4] (Q = CPh2 or CO; R = Me, CMe3, Ph, CH2Cl or CF3) has been found to involve inner-sphere oxidation of carbene or carbonyl ligands during which an oxygen atom transfer occurs from the carboxylate group to the carbene or carbonyl ligand; the thermolysis of the carbonyl clusters gives rise to the products of CO2 insertion into the C H bond of benzene or toluene used as solvents forming benzoic acid from benzene and a mixture of phenylacetic and toluic acids from toluene.

Synthesis and structure of tetranuclear palladium(I) carbonyl clasters

Some palladium(I) carbonyl tetranuclear complexes were synthesized, which, based on the IR spectral and x-ray structure analysis data, contain two long and two short Pd-Pd bonds with two carbonyl and two carboxylate bridges.