Reaction of [(C6H6)RuCl2]2 with 7,8-benzoquinoline and 8-hydroxyquinoline

The reaction of [(C₆H₆)RuCl₂]₂ with 7,8-benzoquinoline and 8-hydroxyquinoline in methanol were performed. The obtained complexes have been studied by IR, UV–VIS, ¹H and ¹³C NMR spectroscopy and X-ray crystallography. In the reaction with 8-hydroxyquinoline the arene ruthenium(II) complex oxidized to Ru(III). The electronic spectra of the obtained compounds have been calculated using the TDDFT method. Magnetic properties of [Ru(C₉H₆NO)₃] · CH₃OH complex suggest the antiferromagnetic coupling of the ruthenium centers in the crystal lattice. EPR spectrum of [Ru(C₉H₆NO)₃] · CH₃OH compound indicates single isotropic line only characteristic for Ru³⁺ with spin equal to 1/2.     

[(CO)2(C5H5)Fe]2C60的合成与表征

有关 C6 0 取代的金属羰基化合物的研究方兴未艾 .C6 0 作为一个特殊的烯烃 ,以六元环间的碳碳双键提供电子对 ,与过渡金属羰基化合物形成诸如 η2 ,η4 ,η6等结构新颖的化合物约有 40多例 [1～ 5] ,但只有一例是以 Fe为中心原子的 C6 0 取代的金属羰基化合物 ( η2 - C6 0 ) Fe( CO) 4 [1] .本文报道了第一例 C6 0配位的 Fe的双核金属羰基化合物 [( CO) 2 ( C5H5) Fe]2 (η2 - C6 0 ) ,并通过元素分析 ,IR,1H NMR,13CNMR和 XPS进行表征 .1　实验部分[Fe( CO) 2 ( C5H5) ]2 购自 Aldrich公司 .C6 0 纯度为 99% .其余试剂均…     

Geometry and nature of the binding of the pre-reactive complex C2H4…ClF from its rotational spectrum

The encounter complex C₂H₄…ClF was isolated by using a fast-mixing nozzle before chemical reaction could occur between the components and was characterised by Fourier-transform microwave spectroscopy. Rotational constants, centrifugal distortion constants, Cl nuclear quadrupole constants and Cl spin-rotation constants were determined for the isotopomers C₂H₄…³⁵ClF and C₂H₄…³⁷ClF. The complex has C_2v symmetry with the ClF subunit perpendicular to the plane of C₂H₄ and oriented so that Cl is closer to C₂H₄. Both the centrifugal distortion constant Δ_J and the Cl nuclear quadrupole coupling constants indicate that the complex is relatively weakly bound and it is concluded that the interaction between the subunits is largely electrostatic in origin.     

C and H nuclear magnetic shielding and spin–spin coupling constants of C-enriched bromomethane in the gas phase

¹³C and ¹H NMR spectral parameters are investigated for ¹³CH₃Br in gaseous matrices. It is found that both the ¹³C and ¹H chemical shifts of ¹³CH₃Br are linearly dependent on solvent density. Similar dependence is also detected for one-bond spin–spin coupling, ¹J(CH). For the first time the ¹³C and ¹H magnetic shielding constants and ¹J(CH) spin–spin coupling are obtained for an isolated ¹³CH₃Br molecule together with the coefficients responsible for solute–solvent molecular interactions in gaseous matrices. The present experimental results confirm the accuracy of some recent ab initio calculations of nuclear magnetic shielding performed for bromomethane.     

Gold(I) complexes with thiolate and triphenylphosphine ligands

The reaction of [AuCl(PPh₃)] with Pb(SR)₂(R = C₂H₅, C₆H₅, CH₂C₆H₅, C₆F₅, C₆H₂Me₃-2,4,6, Prⁱ and Bu^t) provides a clean method to obtain complexes of the type [Au(SR)(PPh₃)] in good yields. The new compounds have been characterized by IR, ¹H, ³¹P, ¹⁹F and ³¹C NMR. A study by FAB mass spectrometry indicates that an ion-molecule aggregation process takes place.     

Alkyl-substituted cyclopentadienyl- and phospholyl-zirconium/MAO catalysts for propene and 1-hexene oligomerization

The directed oligomerization of propene and 1-hexene was carried out with a series of Cp′(C₅H₅)ZrCl₂ and Cp₂′ZrCl₂ pre-catalysts (Cp′=C₅HMe₄, C₄Me₄P, C₅Me₅, C₅H₄^tBu, C₅H₃-1,3-^tBu₂, C₅H₂-1,2,4-^tBu₃) together with (C₅H₅)₂ZrCl₂. Oligomers in the molar mass range 300–1500 g/mol for propene and 200–3000 g/mol for 1-hexene were synthesized at 50 °C. The majority of oligomer molecules contain a double-bond end group. Oligomer characterization was carried out by gel permeation chromatography (GPC), ¹H and ¹³C NMR. Vinylidene double bonds (from β-hydrogen elimination) are solely found for the tert-butyl-substituted zirconocenes and for most of the unsymmetrical methyl-substituted Cp′(C₅H₅)ZrCl₂ systems (except Cp′=phospholyl). With (C₄Me₄P)(C₅H₅)ZrCl₂ and with the symmetrical methyl-containing Cp₂′ZrCl₂ pre-catalysts, also vinyl end groups (from β-methyl elimination) are observed in the case of oligopropenes. The vinylidene/vinyl ratio depends on the ligand and the vinyl content increases from C₅HMe₄ (65/35) over C₄Me₄P (61/39) to C₅Me₅ (9/91). The phospholyl zirconocenes and (C₅HMe₄)₂ZrCl₂ also exhibit chain-transfer to aluminum thereby giving saturated oligomers.     

乙二胺三乙酸与锌(Ⅱ)、钴(Ⅱ)相互作用的固体和溶液化学特性

在水热和弱酸性反应条件下,螯合型表面活性剂前驱体乙二胺三乙酸分别与氯化锌、氯化钴反应,形成水合乙二胺三乙酸金属配合物[M(H₂O)₆][M(ED3A)(H₂O)]₂·2H₂O[M=Zn(1),Co(2);H₃ED3A=乙二胺三乙酸,C₈H₁₄N₂O₆]。 产物经元素分析、红外、热重、液体核磁共振和X射线单晶衍射结构表征。 乙二胺三乙酸和锌(Ⅱ)、钴(Ⅱ)五配位,并与水一起形成典型的[MN₂O₄]或[MO₆]八面体结构。 ¹³C核磁共振实验结果表明,溶液中乙二胺三乙酸与锌形成配合物在弱酸性条件下(pH值3~7)稳定存在,在酸性溶液中完全解离,乙二胺三乙酸进一步经分子内成环反应生成3-酮哌嗪二乙酸(H₂kpda=C₈H₁₂N₂O₅)。     

New Half-sandwich Zirconium（IV） Complexes Containing Salicylaldimine Ligands： Synthesis,Characterizations and Catalytic Properties

Two new half-sandwich zirconium（IV） complexes bearing salicylaldimine ligands of the type Cp＊Zr[2-tBu-4-R-6-（CH=NiPr）C6H2O]C12[R=H（1）, tBu（2）] were prepared by the reaction of Cp＊ZrC13 with the corresponding lithium of salicylaldimine ligands 2-tBu-4-R-6-（CH=NiPr）C6H2OLi[R=H（LiLa）, tBu（LiLb）]. Com- plexes 1 and 2 were characterized by 1H NMR, BC NMR spectroscopy and elemental analysis. When activated with AliBu3 and Ph3CB（C6F5）4, both complexes 1 and 2 exhibited reasonable catalytic activities for ethylene polymeriza- tion, producing polyethylenes with moderate molecular weight. Complexes 1 and 2 also exhibited reasonable catalyt- ic activities for ethylene copolymerization with 1-hexene, producing poly（ethylene-co-l-hexene）s with moderate molecular weight and reasonable 1-hexene content.     

Neodymium Complex Obtained from Reductive-coupling of Carbodiimide: Synthesis and Structure of [(Cp")2Nd(NR)2C-C(NR)2Nd(Cp")2]

A bimetallic oxalamidino complex of neodymium [(Cp")₂Nd(NR)₂C-C(NR')₂Nd(Cp")₂][Cp"=η⁵-C₅H₃-1,3-(SiMe₃)₂, R=C₆H₁₁](2) was obtained via reaction between NdI₂ and carbodiimide[RN=C=NR] (R=C₆H₁₁)(molar ratio 1:1) in tetrahydrofuran(THF) solution, followed by the addition of [KCp"(THF)](1)(molar ratio 1:2) at a low temperature through a reductive-coupling reaction with carbodiimide. The structure of the intermediate product was confirmed by means of elemental analysis, ¹H NMR and ¹³C NMR. Characterization of the product by single crystal X-ray diffraction confirmed the diamidinate type of structure.     

Versatile reactions of a para-bromophenylacetylide iron(II) derivative and X-ray structure of the fluoro analogue. Synthesis of new redox-active organoiron(II) synthons

The synthesis of the new (η²-dppe)(η⁵-C₅Me₅)Fe---CC---1,3-(C₆H₄X) (m-2a/2b; X=F/Br) and (η²-dppe)(η⁵-C₅Me₅)Fe---CC---1,4-(C₆H₄I) (2c) complexes, as well as the solid-state structure of the known (η²-dppe)(η⁵-C₅Me₅)Fe---CC---1,4-(C₆H₄F) (2a) complex are described. The catalytic coupling reactions of the bromo complexes with various alkynes were next investigated. Starting from the known (η²-dppe)(η⁵-C₅Me₅)Fe---CC---1,4-(C₆H₄Br) complex (2b), the synthesis of the (η²-dppe)(η⁵-C₅Me₅)Fe---CC---1,4-(C₆H₄)---CC---H complex (6d) and of the corresponding silyl-protected precursors (η²-dppe)(η⁵-C₅Me₅)Fe---CC---1,4-(C₆H₄)CC---SiR₃ (6b/6c; R=ⁱPr/Me) are reported. By use of lithium---bromine exchange reactions on 2b, the silyl- (7a; E=Si; R=Me) and tin- (7b–7d; E=Sn; R=Me, Bu, Ph) substituted analogues (η²-dppe)(η⁵-C₅Me₅)Fe---CC---1,4-(C₆H₄)ER₃ are also isolated. The spectroscopic and electrochemical characterisations of all these new Fe(II)/Fe(III) redox-active building blocks are presented and the electronic substituent parameters for the “(η²-dppe)(η⁵-C₅Me₅)Fe---CC” group are determined by means of ¹⁹F-NMR.     

Synthesis and crystal structure of the complex [MoW(OEt)(μ-CH2){μ-C(C6H4Me-4)C(Me)O}(η-C7H7)(η-C2B9H10Me)]

The complex [MoW(μ-CC₆H₄Me-4)(CO)₂(η⁷-C₇H₇)(η⁵-C₂B₉H₁₀Me)] reacts with diazomethane in Et₂O containing EtOH to afford the dimetal compound [MoW(OEt)(μ-CH₂){μ-C(C₆H₄Me-4)C(Me)O}(η⁷-C₇H₇)(η⁵-C₂B₉H₁₀Me)]. The structure of this product was established by X-ray diffraction. The Mo---W bond [2.778(4) Å] is bridged by a CH₂ group [μ-C---Mo 2.14(3), μ-C---W 2.02(3) Å] and by a C(C₆H₄Me-4)C(Me)O fragment [Mo---O 2.11(3), W---O 2.18(2), Mo---C(C₆H₄Me-4) 2.41(3), W---C(C₆H₄Me-4) 2.09(3), Mo---C(Me) 2.26(3) Å]. The molybdenum atom is η⁷-coordinated by the C₇H₇ ring and the tungsten atom is η⁵-coordinated by the open pentagonal face of the nido-icosahedral C₂B₉H₁₀Me cage. The tungsten atom also carries a terminally bound OEt group [W---O 1.88(3) Å]. The ¹H and ¹³C-{¹H} NMR data for the dimetal compound are reported and discussed.     

新疆雪莲化学成分研究(Ⅴ)

从新疆雪莲中分出两种新倍半萜类化合物,一种是3α-OH,11β,13-二氢去氢广木香内酯-8-β-D-葡萄糖苷.它的立体结构不同于以前所报道的类似化合物.另一种为新的倍半萜内酯生物碱,经鉴定为13-脯氨酸取代的二氢去氢广木香内酯.命名为大苞雪莲碱(Involucratine).     

Synthese und Charakterisierung von 1,3-dithia-2-boryl-[3]ferrocenophanen

The 1,3-dithia-2-boryl[3]ferrocenophanes (I-VIII) are obtained from the reaction of ferrocene-1,1′-dithiol (A) with dihalogenorganylboranes by elimination of the hydrogenhalides. I-VIII can be also prepared by starting from Fe(C₅H₄SLi)₂ · 2THF (B) inplace of A, but in lower yields. The air-sensitive [3] ferrocenophanes have been characterized analytically and spectroscopically (MS; NMR: ¹H, ¹¹B, ¹³C).     

三乙基铝-单烷基磷酸酯催化体系下的环氧丙烷聚合及13C-NMR谱的研究

使用烷基铝-乙酰丙酮-水体系催化环氧化合物的聚合,可得到分子量百万以上的聚合物,Kida采用三异丁基铝-强磷酸-N,N二甲基苯胺体系对环氧化合物进行催化聚合,Wolfe采用三烷基铝一乙酰丙酮-苯基噻唑-水体系对环氧化合物进行催化聚合,Kuran采用连苯三酚-二乙基锌对环氧丙烷进行催化,并且对聚合物作了¹³C-NMR谱的研究,1985年Bovey等研究了聚环氧丙烷的氢谱,确定了聚环氧丙烷各种异构体的构型。     

Theoretical study on reaction mechanism of the vinyl radical with nitrogen atom

The complex triplet potential energy surface of the C₂H₃N system is investigated at the UB3LYP and CCSD(T) (single-point) levels in order to explore the possible reaction mechanism of C₂H₃ radical with N(⁴S). Eleven minimum isomers and 18 transition states are located. Possible energetically allowed reaction pathways leading to various low-lying dissociation products are obtained. Starting from the energy-rich reactant C₂H₃+N(⁴S), the first step is the attack of the N atom on the C atom having one H atom attached in C₂H₃ radical and form the intermediate C₂H₃N(1). The associated intermediate 1 can lead to product P₁ CH₂CN+H and P₂ ³CH₂+³HCN by the cleavage of C–H bond and C–C bond, respectively. The most favorable pathway for the C₂H₃+N(⁴S) reaction is the channel leading to P₁, which is preferred to that of P₂ due to the comparative lower energy barrier. The formation of P₃ ³C₂H₂+³NH through hydrogen-abstraction mechanism is also feasible, especially at high temperature. The other pathways are less competitive comparatively.     

Synthesis and crystal structures of (C8h8)Nd(C5H9C5H4) (THF)2 and [(C8H8)Gd(C5H9C4H4(THF)][(C8H8)GD(C5H9C5H4(THF)2]

LnCl₃ (Ln=Nd, Gd) reacts with C₅H₉C₅H₄Na (or K₂C₈H₈) in THF (C₅H₉C₅H₄ = cyclopentylcyclopentadienyl) in the ratio of 1 : to give (C₅H₉C₅H₄)LnCl₂(THF)_n (orC₈H₈)LnCl₂(THF)_n], which further reacts with K₂C₈H₈ (or C₅H₉C₅H₄Na) in THF to form the litle complexes. If Ln=Nd the complex (C₈H₈)Nd(C₅H₉C₅H₄)(THF)₂ (a) was obtained: when Ln=Gd the 1 : 1 complex [(C₈H₈)Gd(C_%H₉)(THF)][(C₈H₈)Gd(C₅H₉H₄)(THF)₂] (b) was obtained in crystalline form.

The crystal structure analysis shows that in (C₈H₈)Ln(C₅H₉C₅H₄)(THF)₂ (Ln=Nd or Gd), the Cyclopentylcyclopentadieny (η⁵), cyclooctatetraenyl (η⁸) and two oxygen atoms from THF are coordinated to Nd³⁺ (or Gd³⁺) with coordination number 10.

The centroid of the cyclopentadienyl ring (Cp′) in C₅H₉C₅H₄ group, cyclooctatetraenyl centroid (COTL) and two oxygens (THF) form a twisted tetrahedron around Nd³⁺ (or Gd³⁺). In (C₈H₈)Gd(C₅H₉C₅H₄)(THF), the cyclopentyl-cyclopentadienyl (η⁵), cyclooctatetraenyl (η⁸) and one oxygen atom are coordinated to Gd³⁺ with the coordination number of 9 and Cp′, COT and oxygen atom form a triangular plane around Gd³⁺, which is almost in the plane (dev. -0.0144 Å).     

New cyclic tellurides. Synthesis, reaction and ligand properties of 2,2,6,6-tetramethyl-1-oxa-4-tellura-2,6-disilacyclohexane (C6H16OSi2Te). X-Ray structure determination of C6H16OSi2TeI2

A new tellurium-containing heterocyclic compound, 2,2,6,6-tetramethyl-1-oxa-4-tellura-2,6-disilacyclohexane (C₆H₁₆OSi₂Te) (1), has been prepared by treatment of 1,3-bis(chloromethyl)-1,1,3,3-tetramethyldisiloxane with sodium telluride. Mononuclear and dinuclear palladium complexes of this telluride have been prepared by the reaction of 1 with PdCl₂(PhCN)₂ and Na₂PdCl₄, respectively. The following new derivatives of 1 have also been produced: C₆H₁₆OSi₂TeI₂ (2), C₆H₁₆OSi₂TeBr₂, C₆H₁₆OSi₂TeCl₂, C₆H₁₆OSi₂Te(CH₃)I, and C₆H₁₆OSi₂Te(CH₂Ph)Br. IR, ¹H and ¹³C NMR and mass spectral data of these new compounds are reported and discussed. ¹H NMR studies revealed that in CDCl₃ solution both telluronium salts reductively eliminate alkyl halide. The crystal structure of compound 2 has been determined by X-ray diffraction. The compound crystallizes in the monoclinic space group, P2₁/c, with four molecules in a unit cell of dimension a 12.960(3), b 8.846(2), c 13.754(4) Å, β 92.44(2)°, R = 0.049, and R_w = 0.067 for 3599 unique reflections with |F₀| > 3σ(F₀). The compound forms a six-membered ring of a slightly displaced boat type. The geometry about the Te atom is pseudo-octahedral, with two carbon atoms (Te-C = 2.156(7) and 2.137(6) Å) and two iodine atoms of the neighbouring molecules (weak intermolecular bonds, Te · I = 3.769 and 3.806 Å) in the equatorial positions and two iodine atoms (Te-I = 2.909(1) and 2.913(1) Å) in the axial positions.     

The reaction of (μ-H)2Os3(CO)9(PPh3) with ethylene affords the ethylidene complex (μ-H)2Os3(CO)9(PPh3)(μ-CHCH3)

The product isolated from the reaction of (μ-H)₂Os₃(CO)₉(PPh₃) with ethylene is shown to be the ethylidene complex (μ-H)₂Os₃(CO)₉(PPh₃)(μ-CHCH₃) (1) rather than the ethylene complex (μ-H)(H)Os₃(CO)₉(PPh₃)(C₂H₄), as previously claimed. The characterization of 1 is based on a combination of ¹H and ¹³C NMR results. The ¹H NMR data (δ 6.84 (1 H_D), 2.53 (3 H_C), J(CD) = 7.4 Hz) establish the presence of the ethylidene moiety, whereas detailed analysis of the 1-D and 2-D ¹³C NMR spectra of ¹³CO-enriched 1 indicates the relative positions of the ethylidene, hydride, and phosphine ligands on the triosmium framework.     

Theoretical Studies on Aromaticity of Spiro Metallaaromatics of (C10H10M)2-(M=Ni,Pd, Pt)

Aiming to identify the spiro metallaaromatic systems with potential application value, (C₁₀H₁₀M)^2?(M=Ni, Pd, Pt) derivatives were theoretically investigated. (C₁₀H₁₀M)^2?-Iso1, which has two 6-membered rings(6MRs) connected by the M spiro atom, is a 14π-aromatic as a whole plane. (C₁₀H₁₀M)^2?-Iso2 has one 6π-aromatic 5MR and one 10π-aromatic 7MR connected by the spiro atom. The free (C₁₀H₁₀M)^2? dianions could not exist due to their rather high frontier orbital energies, while the neutral (C₁₀H₁₀M)Li₂ compounds are extremely stable against dissociation. Since (C₁₀H₁₀M)Li₂ coumponds are not fully coordinated, they trend to form (C₁₀H₁₀M)Li₄²⁺ dications, or even[(C₁₀H₁₀M)Li₂]_n polymers. Arguably, (C₁₀H₁₀M)^2? planes are not the only examples for spiro metallaaromaticity, their derivatives are also potential material building blocks.     

Synthese und reaktivität von dienylmetall-verbindungen : XXVII. Ein einfacher weg zur synthese von cyclopentadienylcobalt(III)-dikationen

CpCo(CO)₂ is oxidised by [Cp₂Fe]BF₄ (Cp = C₅H₅) in the presence of neutral ligands L to give the dications [CpCoL₃]²⁺ (L = SMe₂, S(n-C₄H₉)₂, PMe₃, C₅H₅N, MeCN; Me = CH₃). In [CpCo(SMe₂)₃]²⁺, sulfane ligands are substituted by neutral ligands L, L---L and L---L---L, to give the complexes [CpCoL₃]²⁺ (L = SeMe₂, TeMe₂, PMe₃, P(OMe)₃, AsMe₃, SbMe₃, t-C₄H₉NC, C₅H₅N, MeCN), [Cp-Co(L---L)SMe₂]²⁺ (L---L = R₂P(CH₂)_nPR₂, n = 1, 2, R = C₆H₅; bipyridine, o-phenanthroline, neocuproin) and [CpCo(L---L---L)]²⁺ (L---L---L = RP(CH₂CH₂PR₂)₂, R = C₆H₅). The dications react with iodide resulting in the monocations [CpCoL₂I]⁺ and [CpCo(L---L)I]⁺. Azacobaltocinium cations [CpCo(C₄R₂H₂N)]⁺ (R = H, CH₃) are obtained by reaction of [CpCo(SMe₂)₃]²⁺ with metal pyrrolides.