Synthesis,structure, and electrochemistry of mer[RuCl3(DMSO–S)(DMSO–O)(py)]

Reaction of mer-[RuCl₃(DMSO–S)₂(DMSO–O] (1) with pyridine (py) in dichloromethane yields mer-[RuCl₃(DMSO–S)(DMSO–O)(py)] (2). A single crystal suitable for X-ray diffraction was obtained by recrystalization with dichloromethane and diethyl ether. X-ray diffraction analysis revealed an unusual case in which two independent molecules (2a and 2b) are present in the asymmetric unit cell. Both molecules have distorted octahedral geometry in which DMSO is bound through oxygen and sulfur. Density functional theory (DFT) calculations were performed for 2a and 2b in gas phase to investigate bonding shown by the two DMSO ligands. Optimizations were done on both DMSO ligands bonded through S, both DMSO ligands bonded through O, one DMSO bonded through O, and the other through S but opposite to the actual molecule. The energy differences of the optimized structures were calculated.     

Synthesis,crystal structure and Raman spectra of [dabcoH2]CuICl3, [dabcoH2]3Cl4CuIICl4(DMSO) and Cu3Cl3(dabco)(DMSO) (dabco = 1,4-diazabicyclo [2.2.2] octane)

Dissolving elemental copper in a CCl₄–DMSO mixture in the presence of dabco (dabco = 1,4-diazabicyclo [2.2.2] octane) resulted in the formation of a compound with the composition [dabcoH₂][CuCl₃] featuring a univalent copper salt. This compound, composed of discrete dabcoH₂²⁺ cations and CuCl₃^2? anions, represents the first example of a copper(I) chloride derivative containing a doubly protonated [dabcoH₂]²⁺ unit, and a very rare example of the oxidative dissolving of copper in a CCl₄–DMSO mixture to give a Cu(I) compound. The addition of some drops of water to the initial reaction mixture led to the formation of the [dabcoH₂]₃Cl₄CuCl₄(DMSO). Three [dabcoH₂]²⁺ units and four Cl^? anions, bound via N–H…Cl hydrogen bonds, form a horseshoe-like cationic fragment. The divalent copper ion possesses a rather unusual pseudo-tetrahedral surrounding. The comproportionation reaction of CuCl₂·2H₂O and copper powder in the presence of dabco in DMSO results in the formation of the Cu₃Cl₃(dabco)(DMSO) complex. Copper and chlorine ions form unprecedented Cu₆Cl₆ cores, interconnected by neutral dabco linkers into infinite 2-D layers. All the compounds were characterized using the single-crystal X-ray diffraction technique and Raman spectroscopy.     

Synthesis and structure of [Re3S3.7Br4.3(PPh3)3]·0.5CH2Cl2

One of the products of the reaction between Re₃S₇Br₇ and PPh₃ has been isolated in crystalline state and characterized by single crystal X-ray diffraction (XRD), mass-spectrometry, and EPR spectroscopy. The crystalline phase obtained is a co-crystallization product of two cluster complexes: [Re₃(μ₃-S)₂(μ-S)₂(μ-Br)Br₃(PPh₃)₃] (1a) an [Re₃(μ₃-S)₂(μ-S)(μ-Br)₂Br₃(PPh₃)₃] (1b). The ratio 1a:1b in the investigated single crystal sample is ～7:3.     

Conformational analysis and x-ray crystal structure of [(η5-C5H5)Fe(CO)(PPh3)CH2CH3]

The complex [(η⁵-C₅H₅)Fe(CO)(PPh₃)CH₂CH₃] is shown by ¹H NMR spectroscopy and an X-ray crystal structure analysis to adopt a single conformation with the methyl group residing between the cyclopentadienyl and carbon monoxide ligands.     

The oxidative addition of SnCl4 to [W(CO)4(NCMe)(PPh3)]. The X-ray crystal structure of [WH(CO)3(NCMe)(PPh3)2][SnCl5·MeOH]

The oxidative addition reaction of SnCl₄ with [W(CO)₄(NCMe)(PPh₃)] in acetonitrile gives a mixture of seven-coordinate tungsten(II) compounds: [WCl(SnCl₃)(CO)₃(NCMe)(PPh₃)] (1), [WCl₂(CO)₃(NCMe)(PPh₃)] (2), [WCl(SnCl₃)(CO)₂(NCMe)₂(PPh₃)] (3), and [WCl₂(CO)₂(NCMe)₂(PPh₃)] (4) identified by IR and NMR (¹H, ¹³C{¹H}, and ³¹P{¹H}) studies. Treatment of [W(CO)₄(NCMe)(PPh₃)] with 1 equiv. of SnCl₄ in CH₂Cl₂ solution besides compounds 1 and 2 also gives ionic species such as [HPPh₃]⁺ and [SnCl₆]²⁻ and cationic tungsten(II) complexes. The crystal structure of one of these, [WH(CO)₃(NCMe)(PPh₃)₂][SnCl₅·MeOH] (5), has been established by single-crystal X-ray diffraction. The IR, ¹H, ¹³C{¹H} and ³¹P{¹H} spectra of 5 are also described and can be correlated with the crystallographically observed geometry. A notable feature of 5 is the presence of an agostic interaction of the hydride ligand with one of the carbonyl ligands.     

Formation and crystal structure of MeIr(CO)(PPh3)2(MeCO2CHCHCO2Me). Comparison of the structures of analogous alkene and alkyne complexes

The complex MeIr(CO)(PPh₃)₂(MeCO₂CHCHCO₂Me), synthesized from trans-MeIr(CO)(PPh₃)₂ and dimethyl maleate, crystallizes in the centrosymmetric monoclinic space group P2/n with a 13.997(5), b 17.878(5), c 15.709(4) Å, β 91.00(2)°, V 3930(2) ų and Z = 4. X-ray data (Mo-K_α, 2θ 4.5–45.0°) were collected with a Syntex P2₁ automated four-circle diffractometer; the structure was solved and converged with R 5.5% for all 5069 unique reflections and R 4.3% for those 4343 data with |F_o| > 3σ(|F_o|). The iridium(I) center has a distorted trigonal bipyramidal geometry with the Me and CO ligands occupying axial sites (Ir-Me(1) 2.159(8), IrCO 1.907(8) Å. The MeCO₂CHCHCO₂Me ligand is bonded in η² fashion to the iridium, with its coordinated double bond parallel to the equatorial plane. Bonds to the equatorial ligands are IrP(1) 2.344(2), Ir-P(2) 2.376(2) and Ir-(center of olefin) 2.017 Å. The observed ligand configuration is different from that for MeIr(CO)(PPh₃)₂(MeCO₂CCCO₂Me) which has axial Me and PPh₃ ligands in its thermodynamically stable isomer.     

Hydrothermal synthesis of a mixed-valence hexamolybdate cluster: crystal structure of [HN(CH2CH2)3N]2[HMoVMoVI5O19]·[N(CH2CH2)3N]

The hydrothermal reaction of MoO₃, V, Na₂WO₄· 2H₂O, [N(CH₂CH₂)₃N](1,4-diazabicyclo[2.2.2] octane), and H₂O at 160°C for 90h gave dark-brown crystals of [HN(CH₂CH₂)₃N]₂[HMo^VMo^VI ₅O¹⁹]·[N(CH₂CH₂)₃N], (1), in 40% yield. Complex (1) is the first one-electron reduced mixed-valence hexamolybdate to be crystallized and structurally characterized. The crystal structure of (1) consists of discrete [HMo^VMo^VI ₅O₁₉]^2– anions, [HN-(CH₂CH₂)₃N]⁺ cations, and neutral [N(CH₂CH₂)₃N] molecules of crystallization.     

Copper-tungsten complexes with bridging tolylmethylidyne ligands: Crystal structure of the compound [CuW2(μ3-CC6H4Me-4)(CO)4(PPh3)(η-C5H5)2]·CH2Cl2

The complexes [W(CC₆H₄Me-4)(CO)₂(η-C₅H₅)] and [Cu(NCMe)₄][PF₆] in dichloromethane combine to form the salt [Cu&W(CC₆H₄Me-4)(CO)₂(η-C₅H₅)&₂][PF₆], but the latter very readily dissociates in solution releasing the tolylmethylidynetungsten compound. The more stable salt [CuW(μ-CC₆H₄Me-4)(CO)₂(NCMe)(PPh₃) (η-C₅H₅)][PF₆] is obtained by addition of [W(CC₆H₄Me-4)(CO)₂(η-C₅H₅)] to a dichloromethane solution of [Cu(NCMe)₄][PF₆] previously treated with 1 mol equivalent of PPh₃. In the presence of additional PPh₃, however, no copper-tungsten complex is formed. Several reactions of [CuW(μ-CC₆H₄Me-4)(CO)₂(NCMe)(PPh₃)(η-C₅H₅)][PF₆] have been studied, but these led only to release of [W(CC₆H₄Me-4)(CO)₂(η-C₅H₅)]. The compounds [&CuH(PPh₃)&₆] and [W(CC₆H₄Me-4)(CO)₂(η-C₅H₅)] react in toluene at room temperature to give [W(CO)₂(η³-CH₂C₆H₄Me-4)(η-C₅H₅)] and the new cluster compound [CuW₂(μ₃-CC₆H₄Me-4)(CO)₄(PPh₃)(η-C₅H₅)₂]. The structure of the latter species has been established by X-ray diffraction. A CuW₂ metal triangle [CuW 2.640(2) and 2.610(2), and WW 3.064(1) Å] is asymmetrically capped by a CC₆H₄Me-4 group [μ₃-CCu 2.130(9), μ₃-CW 2.035(9) and 2.122(9) Å]. The copper atom is ligated by a PPh₃ molecule, and each tungsten by an η⁵-cyclopentadienyl and two carbonyl groups. The copper atom is weakly coordinated in a semi-bridging manner by two of the CO ligands, one on each tungsten, and is also very weakly bound to a third. The molecule undergoes dynamic behaviour in solution.     

Co(III) and Cr(III) complexes of diphosphadithia ligands and the crystal structure of [CoCl2(L3)]PF6·CH2Cl2 (L3=Ph2P(CH2)2S(o-C6H4)S(CH2)2PPh2)

[CrX₃(thf)₃] (X=Cl or Br) reacts with L (L=L¹–L³ or Ph₂[14]aneP₂S₂) (L¹=Ph₂P(CH₂)₂S(CH₂)₂S(CH₂)₂PPh₂, L²=Ph₂P(CH₂)₂S(CH₂)₃S(CH₂)₂PPh₂, L³=Ph₂P(CH₂)₂S(o-C₆H₄)S(CH₂)₂PPh₂, Ph₂[14]aneP₂S₂=4,8-diphenyl-1,11-dithia-4,8-diphosphacyclotetradecane) and TlPF₆ in MeNO₂ solution to yield the distorted octahedral complexes [CrX₂(L)]PF₆ as green coloured solids in high yield. UV/visible spectroscopy suggests that these are cis-dihalo species and they have also been characterised by IR spectroscopy, electrospray mass spectrometry and microanalyses. The Co(III) analogues [CoX₂(L)]⁺ are readily prepared in a two-stage reaction, involving treatment of CoX₂·6H₂O with L (L=L¹–L³) and NH₄PF₆ in EtOH solution to give a green/brown solid, followed by halogen oxidation of this product in CH₂Cl₂ solution using X₂/CCl₄, to give the final products as brown coloured solids. A mixture of PF₆⁻ and [CoX₄]²⁻ anions are present in the final Co(III) compounds in varying ratios. Crystal structures of [CoCl₂(L²)]₂[CoCl₄]·4H₂O and [CoCl₂(L³)]PF₆·CH₂Cl₂ confirm tetradentate P₂S₂ coordination of L in each case, with mutually cis halogens completing the distorted octahedral geometry. In both cases the complex cation adopts the cis-α form in the solid state and this is also consistent with the solution ³¹P{¹H} NMR spectroscopic data. ⁵⁹Co NMR spectroscopy reveals a very broad single resonance at ≈3200 ppm for these species.     

Synthesis and X-ray crystal structure of the electron-deficient metal carbonyl cluster [Os3(CO)5(μ3-H)(μ-H)(μ-PtBu2)2(μ-Ph2PCH2PPh2)]

The reaction of [Os₃(CO)₁₀(μ-dppm)] (1) with ^tBu₂PH in refluxing diglyme results in the electron-deficient metal cluster complex [Os₃(CO)₅(μ₃-H)(μ-P^tBu₂)₂(μ-dppm)] (2) (dppm = Ph₂PCH₂PPh₂) in good yields. The molecular structure of 2 has been established by a single crystal X-ray structure analysis. In contrast to the known homologue [Ru₃(μ-CO)(CO)₄(μ₃-H)(μ-H)(μ-P^tBu₂)₂(μ-dppm)] (3), no bridging carbonyl ligand was found in 2. The electronically unsaturated cluster 2 does not react with carbon monoxide under elevated pressure, therefore 2 seems to be coordinatively saturated by reason of the high steric demands of the phosphido ligands.     

Synthesis and crystal structure of [MoH3(CCBut)(Ph2PCH2CH2PPh2)2], a trihydrido-alkynyl complex

Reaction of Bu^tCCH with trans-[Mo(N₂)₂(dppe)₂] (dppe = Ph₂PCH₂CH₂PPh₂) gives [MoH₃(CCBu^t)(dppe)₂], whose X-ray structure is reported.     

The synthesis and crystal structure of novel Mo-Sn tetranuclear cubane-like cluster [Mo3(SnBr3)(μ3-O)(μ3-S)3(dtp)3(py)3]·(CH2Cl2)

The synthesis and crystal structure of the first example for hybrid Sn-Mo tetranuclear cubane-like cluster compound containing S/O mixed triple capping atom [Mo₃(SnBr₃)(μ ₃-O)(μ ₃-S)₃(dtp)₃(py)₃]·(CH₂Cl₂) (A) (dtp=S₂P(OC₂H₅)₂) are reported. The compound is prepared by the reaction of [Mo₃(μ ₃-O)(μ-S)₃(dtp)₄·(H₂O)] with SnBr ₃ ^? . The molecular structure of the cluster can be described as a [Mo₃OS₃] core with the SnBr ₃ ^? fragment linked to {Mo₃} triangle by three (μ ₃-S). Three Mo-Mo bond lengths are 2.616(2), 2.620(2), 2.628(2) Å, respectively, and the molecule has approximately C_3v symmetry. There is no bonding between Sn and Mo atoms, however, the addition of SnBr ₃ ^? may cause electron transfer from Sn²⁺ to [Mo₃OS₃] core to result in the shortening of Mo-Mo bond distances. The compound crystallizes in the monoclinic space group P2₁/n with refined lattice parameters ofa=13.012(4),b=22.877(6),c=18.585(6) Å,β=96.34(3)°,V=5498(3)ų, andZ=4. Full matrix refinement converged with final agreement factor ofR=0.054,R _w=0.064.     

Synthesis,crystal structure,and luminescence of a new coordination polymer, {[Cd9(IDC)2(HIDC)6(Bipy)4] · 2N(CH3)(CH2CH3)2 · 2DMF} n

A new cadmium coordination polymer based on imidazole-4,5-dicarboxylic acid (H₃IDC) and 4,4′-bipyridine (Bipy), {[Cd₉(IDC)₂(HIDC)₆(Bipy)₄] · 2N(CH₃)(CH₂CH₃)₂ · 2DMF} _n , has been synthesized under solvothermal conditions and characterized by energy dispersive X-ray spectroscopy, elemental analysis, FT-IR spectroscopy, thermal analysis, and single crystal X-ray diffraction. It crystallizes in the orthorhombic system, space group Pnnm with a = 20.530(2) Å, b = 15.5957(14) Å, c = 16.3846(15) Å, α = β = γ = 90°, V = 5245.9(9) ų, and Z = 2. The complex exhibits a 3-D structure with channels along the c-axis, in which the free N,N-dimethylformamide and methyl-diethyl-amine molecules are located. The thermal behavior and luminescence of this complex have also been studied in the solid state.     

Stereo- and regio-specific CC bond formation via the coupling of electrophilic and nucleophilic organotransition-metal complexes: The x-ray crystal structure of [Ru(CO)2(PPh3)(η2,η3-C8H8R)][PF6]·0.5CH2Cl2 (R = CH2C(Me)CH2)

The coupling of [Ru(CO)₂L(η⁴-cot)] (L = CO or PPh₃, cot = cyclooctatetraene) with [Fe(CO)₃(η⁵-cyclohexadienyl)]⁺ or [Fe{P(OMe)₃}(NO)₂(η³-allyl)]⁺ yields respectively the dimetallic species [Ru(CO)₂L(η²,η³-C₈H₈{Fe(CO)₃(η⁴-C₆H₇)}] (3) and the allyl-substituted derivative [Ru(CO)₂L(η⁵-C₈H₈CH₂C(Me)CH₂)][PF₆] (5) whose X-ray structure is reported; paramagnetic [Co(η-C₅H₅)₂] and [Ru(CO)₃(η⁵-cyclohexadienyl)]⁺ give diamagnetic [Ru(CO)₃(η⁴-C₆H₇C₅H₆(o-C₅H₅)] (8) via CC bond formation and one-electron reduction.