Trimethylphosphine Ligands Research Articles

Synthesis and X-ray structural characterization of the seven-coordinate niobium oxo complex, [Nb(O)Cl 3(PMe 3) 3]; the first tertiary phosphine adduct of Nb(O)Cl 3

Treatment of Nb(O)Cl 3 with three equivalents of trimethylphosphine in dichloromethane affords the seven-coordinate niobium oxo complex, [Nb(O)Cl 3(PMe 3) 3] in 80% yield. The crystals are monoclinic, space group P2 1/ c with unit cell parameters a = 15.250(3), b= 11.131(2), c = 11.673(3) Å, β = 93.61(2)°, U = 1977.54 Å 3 and Z = 4. The niobium coordination geometry is distorted mono-capped octahedral with the oxo group capping the face defined by the trimethylphosphine ligands.

The reactions of alkyltrimethylphosphinenickel complexes with isocyanides and alkynes

t-Butylisocyanide reacts with NiRCl(PMe 3) 2 (R  CH 3, Ia; R  CH 2SiMe 3, Ib) to give, successively, the products of mono- and di-insertion into the nickelcarbon bonds; with more than two equivalents of isocyanide, trimethylphosphine ligands are displaced. In contrast to related palladium reactions, cyclohexyl isocyanide gives mono-insertion products only, while benzyl isocyanide is polymerised. The reactions of diphenylacetylene with Ia and Ib in methanol give ( Z) vinylnickel complexes, trans-Ni{C(Ph)C(Ph)R}Cl(PMe 3) 2, while from reaction in diethyl ether a precursor complex [NiMeCl(PMe 3) 2 · (PhCCPh) 0.5] can be isolated. On heating the ( Z)-vinyl complexes come into thermodynamic equilibrium with their ( E)-isomers. The vinyl complexes are stereochemically rigid and resistant to further insertion.

ChemInform Abstract: Synthesis, Structure, and Reactivity of Trimethylphosphine‐Zirconocene Thioaldehyde Complexes.

AbstractThe zirconocene thioaldehyde complexes (IV), which are stabilized by coordination of a trimethylphosphine ligand, are prepared simply by treatment of (I) with a thiol (II) and heating the resulting compounds (III) in the presence of trimethylphosphine.

Structure of a mononuclear ruthenium(II) complex containing carboxylato and trimethylphosphine ligands and an aqua ligand

Aquabis(trifluoroacetato)tris(trimethylphos- phine)ruthenium(II), (Ru(C2F302)2(C 3HgP)3(H20)), M r= 573.35, monoclinic, P21/c, a = 15.849 (7), b =8.760(4), c=17.398(3)A, fl=90.21(2) ° , U= 2415.5 A 3, Z = 4, D x = 1.58 Mg m -3, Mo K(~ radiation, it = 0.71069 A, /~ = 0.81 mm -~, F(000) = 1160, T= 295 K, R = 0.0452 for 2594 unique reflec- tions with F o >4g(Fo). The octahedral complex is mononuclear with three trimethylphosphine ligands in a facial configuration. The coordination sphere of the Ru atom is completed by two monodentate trifluoro- * To whom all correspondence should be addressed.

Synthesis and molecular and crystal structure of the octanuclear palladium cluster Pd 8(μ 3-CO) 2(μ 2-CO) 6(PMe 3) 7

Treatment of bis(dibenzylideneacetone)palladium with trimethylphosphine under a carbon monoxide atmosphere gives the title complex in good yield. X-ray crystallography has shown the structure of the complex to consist of an octahedron of palladium atoms which is bicapped by two further palladium atoms in an asymmetric fashion. Seven of the eight palladium centres carry terminal trimethylphosphine ligands. Two face-bridging and six edge-bridging CO molecules complete the ligand shell.

Crystal and molecular structure of(η 5-C 5H 5)W[C 3(CME 3) 2Me](PME 3)Cl 2, a species with a tetrahedral WC 3, core formed from a tungstenacyclobutadiene complex via attack on tungsten by a phosphorus-donor ligand

The complex (η 5-C 5H 5)W[C 3(CMe 3) 2Me](PMe 3)Cl 2, prepared previously by the reaction of the tungstenacyclobutadiene complex (η 5-C 5H 5) W[C(Ph)C(CMe 3)C (Ph)]Cl 2 with PMe 3, has been subjected to a single-crystal X-ray diffraction study. This complex crystallizes in the centrosymmetric monoclinic space group P2 1/ c (C 2h 5; No. 14) with a 10.302(3) Å, b 15.314(3) Å, c 14.130(2) Å, β 98.036(16)°, V 2207.4(8) Å 3 and Z = 4. Diffraction data (Mo- K α, 2θ 4.5–50.0°) were collected with a Syntex P2 1 automated four-circle diffractometer and the structure was refined to R 4.7% for all 3919 independent reflections ( R 3.4% for those 3290 data with | F 0| > 3σ(| F 0|)). The molecular geometry approximates that of a “four-legged piano stool” with the tungsten atom surrounded by an η 5-cyclopentadienyl ligand, two chloride ligands (WCl(1) 2.538(2) Å, WCl(2) 2.504(2) Å) a trimethylphosphine ligand (WP 2.600(2) Å) and an η 3-[C 3(CMe 3) 2Me] ligand. The three carbon atoms of the C 3 ring are tightly bound to tungsten (WC(1) 2.139(5) Å, WC(2) 2.150(6) Å WC(3) 2.200(6) Å) and the WC 3 core of the molecule is closer to a “tungstenatetrahedrane” moiety than to the more familiar η 3-cyclopropeniumtungsten (i.e., C 3H 3 +) representation; the C 3 ring is perhaps best termed an η 3-cyclopropenyl system.

Tetraborane(8) adducts of strongly basic phosphines

Abstract : Four methods were developed for the preparation of B4H8.P(CH3)3. the removal of one of thhe trimethylphosphine ligands from B4H8.2P(CH3)3 by B2H6, the hydride removal from B4H9P(CCH3)3byB2H6, the boron framework expansion of B3H7THF with the use of B2H42P(CH3)3 and the reaction of B3H62P(CH3)3B3H8- with trimethylamine. The yields were better than 90%. The adduct of tris(dimethylamino)phosphine, B4H8.P(N(CH3)2)3 was prepared from the above mono(phoshine)adducts. These were B4H8P(N(CH3)3N(CH3)3N(CH3)3, and B4H8P(CH3) 3P(N(CH3)2)3. The former existed in two isometric forms, each being different from the other in the positions of the two different ligands. These compounds were characterized by their 11B1H, and 31P NMR spectra. Originator-supplied keywords include: Boranes, Phoshines, Lewis Bases.

Preparations of Cyclopentadienylruthenium Complexes with Trimethylphosphine Ligands

Abstract The reaction of Ru(C, -H 5)(PPh 3) 2Cl with PMe 3 in the polar solvent EtOH, followed by metathesis, gives [Ru(C 5H 5)(PPh 3) 2(PMe 3)]PF 6. However in a less polar solvent, toluene, the reaction proceeds in a different manner, giving Ru(C 5H 5)(PMe 3) 2Cl. A reaction with dpe occurs in a similar fashion to give Ru(CrHg)(dpe)Cl. The compounds, Ru(C 5H 5)(PMe 3) 2X (X = Br, I, SCN), can be prepared from the chloride complex by anion exchange, and the compound with x = SnCU can be prepared by addition of SnCl 2 to this precursor. Ionic complexes [Ru(C 5H 5)(PMe 3) 2L]X (L = PMe 3, CO, PPh 3) are formed from Ru(CgH 5)-(PMe 3) 2Cl and these several ligands in polar solvents; these cations were metathesized with NHPF, and isolated as PF, salts. The reaction of Ru(C 5H 5)(PMe 3) 2Cl with AgBF 4 in MeCN gives [Ru(C 5H 5)(PMe 3) 2(MeCN)]BF 4and the reaction with NOPF & gives [Ru(C 5H 5)(PMe 3) 2(NO)](PF 6) 2> The reaction of Ru(C 5H 5)(CO) 2Cl with PMe 3 gives predominately [Ru(C 5H 5)(CO)-(PMe3)2]+ wher...

Nuclear magnetic resonance spectra of complexes of platinum(II), palladiurn(II), platinum(IV), rhodium(III), and iridium(III) containing three or four trimethylphosphine ligands

The 1H n.m.r. spectra of [MX(PMe3)3][NO3](M = Pd or Pt), mer-[PtX3(PMe3)3][NO3], mer- and fac-MX3(PMe3)3, trans-[MX2(PMe3)4]+(M = Rh or Ir, X = Cl or Br), [Ptl(PMe3)3][NO3], and [Pt(PMe3)4][BF4]2 are reported and discussed, together with data from 1H{31P} INDOR measurements. The signs of several of the couplings have been determined by heteronuclear double resonance. A partial analysis is presented for the spectra of the [AXn]4(planar) systems.

Synthèse et configuration d'un complexe pentacoordiné dérivé du nickel carbonyle: diiodocarbonyle bis(triméthylphosphine)nickel

Preparation of compound NiI 2(CO)[P(CH 3) 3] 2 from Ni(CO) 2[P(CH 3) 3] 2 and iodine or NiI 2[P(CH 3) 3] 3 and carbon monoxide is presented. These are the first syntheses of dihalogen derivatives of nickel carbonyl. The diiodocarbonylbis(trimethylphosphine) nickel very likely has a trigonal bipyramidal structure with the two axial positions occupied by trimethylphosphine ligands.