Sulfur-assisted chloride and triphenylphosphine dissociation of palladium(II) complex [Pd(PPh3)2(η1-SCNMe2)(Cl)]. X-ray structures of [Pd(PPh3)2(η1-SCNMe2)(Cl)], [Pd(PPh3)(Cl)]2(μ,η2-SCNMe2)2, and [Pd(PPh3)2(η2-SCNMe2)][PF6]

Treatment of Pd(PPh₃)₄ with Me₂NC(S)Cl in dichloromethane at −20 °C produces the complex [Pd(PPh₃)₂(η¹-SCNMe₂)(Cl)], 2. Variable temperature ¹H and ³¹P{H} NMR experiments of complex 2 shows the dissociation of either the chloride or the triphenylphosphine ligand to form complex [Pd(PPh₃)₂(η²-SCNMe₂)][Cl], 3 or the dipalladium complex [Pd(PPh₃)Cl]₂(μ,η²-SCNMe₂)₂, 4. The reaction of complex 2 with NaPF₆ affords complex [Pd(PPh₃)₂(η²-SCNMe₂)][PF₆], 5. Complexes 2, 4, and 5 are characterized by X-ray diffraction analyses.     

Preparation of Ru(η3-2-alkenylallyl)(CO)Cl(PPh3)2 complexes via carbometallation of allenes with alkenyl ruthenium complexes

Alkenyl ruthenium complex, Ru(CHCHR)(Cl)(CO)(PPh₃)₂ 1, reacted with allenes 2 to give η³-allyl ruthenium complexes, Ru(η³-2-alkenylallyl)(Cl)(CO)(PPh₃)₂ 3, in good yields. The reaction depends on the structure of the alkenyl group. When R was phenyl or methoxycarbonyl group, the carbometallated complex 3 was yielded as a sole product. However, when R was butyl or trimethylsilyl group, besides the carbometallation product as main product, was obtained a small amount of 2-unsubstituted η³-allyl ruthenium complex which was formed via β-elimination of the alkenyl complex followed by the reaction with allene. Structure of 3 was determined by the X-ray crystal structure analysis.     

Migratory insertion reaction in alkenyl ruthenium(II) complexes containing a trifluoroacetate ligand. X-ray structure of the Ru(η2- O2CCF3)(η1-OCCHCHtBu)(CO)(PPh3)2 complex

Reaction of compound Ru(O₂CCF₃)(CHCH^tBu)(CO)(PPh₃)₂ with CO gives the η¹-alkeneacyl complex Ru(O₂CCF₃)(OCCHCH^tBu)(CO)(PPh₃)₂, which is in equilibrium with the dicarbonyl Ru(O₂CCF₃)(CHCH^tBu)(CO)₂(PPh₃)₂ derivative in CH₂Cl₂ solution. The η¹-acyl form involves an η¹-coordination of the O₂CCF₃ ligand, whereas the dicarbonyl form contains the carboxylate ligand η²-coordinated to the metal. The same mixture of carbonylated compounds can be obtained from the reaction of Ru(CHCH^tBu)Cl(CO)₂(PPh₃)₂ with Na[O₂CCF₃] in a CH₂Cl₂/MeOH solution. These reactions reveal the significance of ancillary bidentate ligands for the η-nature of the acyl–metal bond. The molecular structure of the complex Ru(O₂CCF₃)(OCCHCH^tBu)(CO)(PPh₃)₂ was established by X-ray diffraction study of a monocrystal obtained from a CH₂Cl₂/MeOH solution of the mixture of carbonylated compounds.     

An unusual intramolecular metallalactone formation from coordinated alkoxide and CO: molecular structure of Au3Ru3{μ3-η1:η1:η1,η2-CCHCPh2OC(O)}(CO)8(PPh3)3

Sequential treatment of Ru₃(μ-H){μ₃-C₂CPh₂(OH)}(CO)₉ with K[BHBu^s₃] and AuCl(PPh₃) afforded Au₃Ru₃{μ₃-η¹:η¹:η¹,η²-CCHCPh₂OC(O)}(CO)₈(PPh₃)₃, formed by intramolecular attack of alkoxide on an adjacent CO ligand, and characterised by a single-crystal X-ray study.     

Thermal dehydration of Y(TFA)3(H2O)3: Synthesis and molecular structures of [Y(μ,η1:η1-TFA)3(THF)(H2O)]1∞ · THF and [Y4(μ3-OH)4(μ,η1:η1-TFA)6(η1-TFA)(η2-TFA)(THF)3(DMSO)(H2O)] · 6THF (TFA = trifluoroacetate)

In order to obtain a better anhydrous precursor for various applications in materials science and catalysis, thermal dehydration reactions of Y(TFA)₃(H₂O)₃ (TFA = trifluoroacetate) (A) were investigated. Thermal treatment of A at different temperatures under vacuum (5 × 10^?2 mm) for several hours failed to give totally anhydrous yttrium trifluoroacetate (as indicated by IR). Two different complexes, a partially dehydrated [Y(μ,η¹:η¹-TFA)₃(THF)(H₂O)]_1∞·THF (1) and a partially hydrolyzed [Y₄(μ₃-OH)₄(μ,η¹:η¹-TFA)₆(η¹-TFA)(η²-TFA)(THF)₃(DMSO)(H₂O)] · 6THF (2), were obtained with good and moderate yield, respectively, by crystallization of two different thermally treated batches of A from THF (or THF + DMSO) at room temperature. More efficient dehydration of A could be achieved at 200 °C in a furnace, the obtained anhydrous yttrium tris-trifluoroacetate giving Y(TFA)₃(THF)₂ (3) on crystallization from THF. All the products were characterized by elemental analyses, FT-IR and ¹H NMR spectroscopy as well as thermo-gravimetric analysis. In addition, single crystal X-ray structures are reported for 1 and 2, which show either a terminal (η¹ and η²) or bridging (μ,η¹:η¹) bonding behavior of the TFA ligand.     

Ru4(μ-CO)(CO)9(η4-μ4-C6H4)(η2-μ1,μ4-PPhCH2CH2PPh2): an unusual pyrolysis product of Ru3(CO)10(dppe) containing a benzyne ligand

The thermal decomposition of Ru₃(CO)₁₀(dppe) in refluxing benzene gives, in contrast to the pyrolysis of the dppm analogue, the tetranuclear cluster Ru₄(μ-CO)(CO)₉(η⁴-μ₄-C₆H₄)(η²-μ₁,μ₄-PCH₂CH₂PPh₂) (1) along with Ru₃(CO)₉(η²-μ₁,μ₂-C₆H₅)(η³-μ₁,μ₂-PPhCH₂CH₂PPh₂) (2). The single-crystal structure analysis of 1 reveals a square-planar tetraruthenium skeleton containing a η⁴-μ₄-benzyne ligand as well as a η²-μ₁,μ₄-phosphinidene–phosphine ligand.     

Synthesis of UHMW-PE by a Highly Active Homogeneous System: η5-(C5H5)2Ti(η1-OC(O)C6H5)2/MAO

Summary The complex ⁵-(C₅H₅)₂Ti (¹-OC(O)C₆H₅)₂ was synthesized and activated with MA0 for ethylene polymerization. The resultant polymer is UHMW-PE with a viscosimetric molecular weight of Mv = 6.8 x 10⁶ to 0.7 x 10⁶ g/mol dependent on the temperature of the reaction. The effects of the Al/Ti molar ratio and temperature of the reaction on the catalytic activity and polymer properties were studied.     

Synthesis and nanostructure of [Mo(C6H4O2)3]·2(C4H8N2O) and the synthesis from 1,2-PDA to (C4H8N2O)

Continuing our work on the synthesis of MoO₂L₂ and MoO₃L_AL_B that show excellent anti-cancer activities in vitro, the MoL₃ have been synthesized by the solvothermal reaction of Na₂MoO₄ with catechols and 1,2-DPA in the mixed solvent of MeCN/MeOH. X-ray diffraction revealed that Mo in chiral octahedral geometry coordinate with three catechol ligands formed three five-membered rings, and the [Mo(C₆H₄O₂)₃] are linked by hydrogen bonds Mo(OC₆H₄)O…H–N(C₄H₈O)N–H…O(C₆H₄O)Mo through the by-product (C₄H₈N₂O) that are formed by one 1,2-DPA with one CO₂ on the catalysis of Mo-complex. Also, we have disassembled bulk crystal into nano-aggregates, and under TEM mono-lamella morphology of nanostructures was observed, which agrees well with the previous conclusion that the morphologies of the nano-aggregates are associated with the quantum motifs in their crystal lattices. [Mo(C₆H₄O₂)₃] have also been characterized by UV–vis spectra, cyclic voltammogram and thermogravimetric analysis.     

Synthesis and X-ray characterization of the new pentanickel cluster cation [Ni5(μ5-S)(μ3-S)2(μ2-S)(μ-CH3COO)(PPh3)5]+

By reacting Ni(CH₃COO)₂·6H₂O with H₂S in the presence of PPh₃, the new Ni/S cluster of formula [Ni₅(μ₅-S)(μ₃-S)₂(μ₂-S)(μ-CH₃COO)(PPh₃)₅]PF₆·C₇H₈·0.5CH₂Cl₂ has been isolated and characterized by X-ray diffraction analysis. Crystal data: space group P2₁/c, a=15.774(4), b=21.235(7), c=29.288(7) Å, β=95.66(4)°. The inner core consists of a square pyramid of five nickel atoms, linked together by a bridging acetate and four variously bridging sulfur ligands. The ³¹P{¹H} NMR spectra in dichloromethane solution are consistent with the above geometry.     

Molecular structure of [In2(μ,η1-OR)(μ,η2-OR)(η2-OR)3(η1-OR)] R = C2H4NMe2, a pincer ligand

Functional indium [In(OR)₃]_m alkoxides (R = C₂H₄OMe, C₂H₄NMe₂) have been obtained by alcoholysis of In[N(SiMe₃)₂]₃ and characterised by elemental analysis, FT-IR and NMR spectroscopy. The 2-dimethylaminoethoxide was characterised by X-ray diffraction. It corresponds to the association of two InO₆ octahedra giving the unsymmetrical dimer [In₂(μ,η¹-OR)(μ,η²-OR)(η²-OR)₃(η¹-OR)] (2). 2 was used as a pincer ligand toward Cu(acac)₂.     

Synthesis and crystallographic characterisation of Mg(H2dhtp)(H2O)5·H2O

A mononuclear complex of composition Mg(H₂dhtp)(H₂O)₅·H₂O has been prepared and characterised crystallographically.     

Diastereotopic relationship between planar and central chiralities in the formation of Ru(η3-allyl)(CO)(PPh3)(L–L′) complexes

Hydride ruthenium complexes, RuHCl(CO)(PPh₃)₂(L–L^′) 3 (L–L^′=bidentate ligand having nitrogen and oxygen) react with allenes to give Ru(η³-allyl)(CO)(PPh₃)(L–L^′) complexes 5 in good yields via hydrometalation reaction. The complexes 5 have planar chirality at the η³-allyl ligand and central chirality at the Ru metal, and consist of one pair of enantiomers. Ligand substitution reaction of Ru(η³-allyl)Cl(CO)(PPh₃)₂ complexes 6 with bidentate ligands (L–L^′) also afford the complexes 5 which have the same stereochemistry as those formed by the hydrometalation reaction. The planar chirality is controlled by the central chirality at the Ru metal in both the formations of the complexes 5. The structure of 5a (L–L^′=N–N bidentate ligand) was determined by the X-ray crystal structure analysis.     

Solvent/C60 exchange on Ir(CO)(PPH3)2(Cl)(η2-C60) and solvent/solvent’ exchange on Ir(CO)(PPH3)2(Cl)(solvent)

Dissociation of C₆₀ from Ir(CO)(PPh₃)₂(Cl)(η²-C₆₀) in a binary mixture of solvents (solvent₁ and solvent₂) produced non-equilibrium mixtures of Ir(CO)(PPh₃)₂(Cl)(solvent₁) and Ir(CO)(PPh₃)₂(Cl)(solvent₂). Once the solvated species were produced, they underwent a relative fast solvent exchange between them to produce an equilibrium mixture.     

Reactivity of [WCl(SnCl3)(CO)3(NCMe)2] towards tBuCCH.: X-ray crystal structure of [WCl(CO)(tBuCCH)(NCMe)(PPh3)2]2[SnCl6]

In the reaction of [WCl(SnCl₃)(CO)₃(NCMe)₂] with tert-butylacetylene the very labile bis(alkyne) complex [WCl(SnCl₃)(CO)(^tBuCCH)₂(NCMe)] has been observed as the major product by means of IR and NMR spectroscopy. The latter compound in reaction with two equivalents of PPh₃ in CH₂Cl₂ solution gives very poorly soluble purple crystals of the tungsten(II) cationic complex. The crystal structure of this compound consists of the discrete [SnCl₆]²⁻ anion, two independent [WCl(CO)(^tBuCCH)(NCMe)(PPh₃)₂]⁺ cations and four MeCN (solvent) molecules. This is the first crystallographically characterized cationic chlorocarbonyl complex of tungsten(II) containing a terminal alkyne as ligand.     

Characterization of rigid endo- and exo-η3-allyl carbonyl diethyldithiophosphate molybdenum complexes: crystal structure of endo-Mo(η3-allyl)(CO){η2-S2P(OEt)2}(Dppe)

The stereochemical rigid complexes endo-Mo(η³-allyl)(CO){η²-S₂P(OEt)₂}(η²-dppm) (2a) and exo-Mo(η³-allyl)(CO){η²-S₂P(OEt)₂}(η²-dppm) (2b) are accessible by the reaction of complex Mo(η³-allyl)(CO)₂{η²-S₂P(OEt)₂}(CH₃CN) (1) with dppm in refluxing acetonitrile. Treatment of 1 with dppe in the similar reactive conditions of 2 affords the sole complex endo-Mo(η³-allyl)(CO){η²-S₂P(OEt)₂}(η²-dppe) (3). Complex 3 is characterized by X-ray diffraction analysis.     

Formation of [8,8-η2-{(μ-Cl)2Ru(η6-p-cym)Ph2PCH2PPh2}-nido-8,7-RhSB9H10], a bimetallic derivative of the novel species [8,8-(η2-dppm)-8-(η1-dppm)-nido-8,7-RhSB9H10]

Treatment of [8,8-(η²-dppm)-8-(η¹-dppm)-nido-8,7-RhSB₉H₁₀] (I) with [Ru(η⁶-p-cym)Cl₂]₂ leads to the formation of a new bimetallic complex, [8,8-η²-{(μ-Cl)₂Ru(η⁶-p-cym)Ph₂PCH₂PPh₂}-nido-8,7-RhSB₉H₁₀], (II) containing the group [(μ-Cl)₂Ru(η⁶-p-cym)Ph₂PCH₂PPh₂] that coordinates in a multidentate mode to Rh.     

Synthesis of Selective Sorbent LiCl ⋅ 2Al(OH)3 ⋅ nH2O

Theoretical Foundations of Chemical Engineering - A synthesis process of selective layered sorbent LiCl ? 2Al(OH)3 ? nH2O from a mixture of LiCl + AlCl3 + NaOH + H2O solutions with the...     

Phosphorus–carbon bond cleavage of Ph2PCH2PPh2 at a triruthenium center: synthesis and structural characterization of [Ru3(μ-CO)(CO)6(μ-PPh2)2(μ3-CH2PPh)]

The reaction of Ph₂PH with [Ru₃(CO)₁₀(μ-dppm)] (1) at 98°C gave [Ru₃(μ-CO)(CO)₆(μ-PPh₂)₂(μ₃-CH₂PPh)] (7) in 20% yield. Compound 7 was characterized by elemental analysis, ¹H and ³¹P{¹H} NMR and mass spectroscopic data and also by a single crystal structure determination. The compound is shown to consist of a triruthenium cluster with an unusual example of a triply bridging CH₂PPh ligand and two doubly bridging PPh₂ ligands.