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1.
The P-functional organotin dichloride [Ph2P(CH2)3]2SnCl2 (3) is synthesized by reaction of Ph2P(CH2)3MgCl with SnCl4 independently of the molar ratio of the starting compounds. The corresponding organotin trichlorides Ph2P(CH2)nSnCl2R (4: n=2, R=Cl; 5: n=3, R=Cl; 6: n=3, R=Me) are formed in a cleavage reaction of Ph2P(CH2)nSnCy3 (n=2, 3) with SnCl4 or MeSnCl3, respectively. The main features of the crystal structures of 3–6 are both intra- and intermolecular PSn coordinations and the existence of intermolecular Sn---ClSn bridges. For further characterization of the title compounds, the adducts 4(Ph3PO)2 (7) and 5(Ph3PO) (8), as well as the P-oxides and P-sulfides of 3–6 (9–15), are synthesized. The results of crystal structure analyses of 7, 11, 12, and 14 are reported. The structures of 9–15 are characterized by intramolecular P=XSn interactions (X=O, S). A first insight into the structural behavior of the compounds 3–15 in solution is discussed on the basis of multinuclear NMR data.  相似文献   

2.
A study has been made of asymmetric hydroformylation of styrene with PtCl2(PPh3)2 + bisphosphine + SnCl2 (bisphosphine: BDPP = (−)-(2S,4S)-2,4-bis(diphenylphosphino)pentane or DIOP = (−)-(4R,5R)-2,2-dimethyl-4,5-bis(diphenylphosphinomethyl)-1,3-dioxolane) and PtCl2(bisphosphine) + PPh3 + SnCl2 catalysts prepared “in situ”. The presence of an excess of the phosphine ligand slightly lowered the reaction rate, but the enantioselectivity of these systems is significantly higher than those involving PtCl(SnCl3)(bisphosphine) catalysts. Under mild reaction conditions 88.8% enantiomeric excess was achieved. Replacing SnCl2 in these catalysts by CuCl2 or CuCl gave a new homogeneous catalytic system which is active at higher reaction temperature (> 100°C), but has a rather moderate enantioselectivity.  相似文献   

3.
The direct reaction between [TiCl4(THF)2] and SnCl2 in tetrahydrofuran (THF) yields the green paramagnetic salt [trans-TiCl2(THF)4][SnCl5(THF)]. The same compound is also formed in the reaction between [TiCl3(THF)3] and SnCl4 in THF. Crystals of the title compound are monoclinic with a = 8.442(4), b = 21.589(9), c = 9.262(5) Å, β = 107.91(5)°, Z = 2, space group P21/m. Both metal ions are in an octahedral environment. The titanium atom in the cation [TiCl2(THF)4]+ lies on the symmetry centre. The tin atom in [SnCl5(THF)] is located on the mirror plane.  相似文献   

4.
The reaction between Ru3(CO)12 and a cyclic olefin (cis-cyclooctene or trans-cyclododecene) at 100 °C for several hours gives the title compounds (μ-H)2RU3(CO)932-C8H12) (1), and (μ-H)RU3(CO)933-C12H19) (2), both of which have been characterized by X-ray diffraction studies, IR and NMR spectral measurements and elemental analysis. The prolonged reaction between Ru3(CO)12 and cis-cyclooctene gives compound HRu3(CO)9(C8H11) (3). Compound 3 has been characterized with IR and NMR spectral analyses. In 1 the cyclooctene ring is linked via a μ32-alkyne type of bonding to the face of the Ru3 cluster. It is formally σ-bonded to two of the three Ru atoms and π-bonded to the third Ru. The two hydrides in 1 are bridging Ru---Ru bonds. In 2 the cyclododecene ring is bonded to the Ru3 face via the μ33-CCHC linkage. There are two formal σ-bonds from the allyl part to the hydrido-bridged Ru atoms and the η3-allyl linkage to the third Ru atom.  相似文献   

5.
Reaction of the bis(dihydrogen) ruthenium complex RuH2(H2)2(PCy3)2 (1) with an excess of 9-borabicyclononane yields Ru[(μ-H)2BC8H14]2(PCy3) (6) and the phosphine adduct PCy3·HBC8H14. The new complex is characterized by NMR spectroscopy and X-ray diffraction. New X-ray data on 9-BBN dimer, from a measurement at 180 K, are also reported. DFT calculations (B3LYP) on Ru[(μ-H)2BC8H14]2(PMe3) (7), the PMe3 analogue of 6, confirm the ruthenium (II) formulation with two dihydroborate ligands. The data obtained using PH3 or PMe3 as models for PCy3 in PR3·HBC8H14 are also discussed.  相似文献   

6.
A palladium precursor and SnCl2 as cocatalyst were used under 4 MPa of carbon monoxide for the catalytic alkoxycarbonylation of several monoterpenes into C11 esters. The active catalyst involves a palladium-hydride species whose formation was investigated. In the case of the model substrate 3-phenylpropene, the source of the hydrido ligand was determined to be the alkene itself. Allylic hydrogen abstraction seems to be a general way to produce the active hydridopalladium species since monoterpenes having labile allylic hydrogens were converted under exceptional mild conditions. An X-ray crystal structure analysis was carried out on [(Ph3PCH2CH =MPh)4(PdCl6)(SnCl6)]. kw]Palladium; X-ray structure; Terpenes; Carbonylation; Hydroesterification  相似文献   

7.
Reaction of Ru(PPh3)2Br2 with the NNS chelating tridentate ligand 2-pyridyl-N-(2′-methylthiophenyl)methyleneimine (L) led to the isolation of the ruthenium(II) complex [Ru(L)(PPh3)Br2]. Reactivity of this complex with different bidentate chelating ligands revealed that the products are quite different from those obtained by reacting Ru(L)(PPh3)Cl2 (the corresponding cis dichloro complex) with the same ligands under comparable conditions. The mixed chelates were isolated and characterised by elemental analysis, magnetic moment measurement and by different spectroscopic methods along with their precursor. Electrochemistry of the complexes was examined by cyclic voltammetry using a platinum working electrode and a Ag/AgCl electrode as reference. The crystal structure of [Ru(L)(PPh3)Br2] disclosed that, unlike Ru(L)(PPh3)Cl2, the two bromo ligands are in trans position and this explained the difference in its reactivity pattern from the corresponding chloro complex.  相似文献   

8.
The ionic coupling of [Os4H2(CO)12]2− with [Ru(η6-C6H6)(MeCN)3]2+ affords the neutral mixed metal cluster Os4Ru(μH)2(CO)12(η6-C6H6) 1. The reaction of 1 with trimethylphosphite leads to the initial formation of the addition product Os4Ru(μH)2(CO)12(η6-C6H6)P(OMe)3 2, but this complex rearranges in solution to give Os4Ru(μ-H)3(CO)12(μ3-η6-C6H5)P(OMe)3 3. An X-ray structure of 3 shows that the metal core of the cluster is a ruthenium-spiked Os4 tetrahedron, with one hydrogen atom from the arene having transferred to the Os4 core, and one arene carbon bridging an Os-Os edge, while the ring as a whole remains η6-bound to the Ru atom.  相似文献   

9.
以Al2O3为载体,RuCl3·xH2O及Ni(NO32·6H2O为活性组分前驱体,采用吸附-沉淀法制备系列Ru-Ni/Al2O3催化剂,以马来酸二甲酯(DMS)催化加氢为探针反应,考察了活化条件和Ni的添加量对催化剂性能的影响。随Ni负载量的升高,Ru-Ni/Al2O3催化剂活性呈现先升高后降低的趋势,在Ni:Ru的原子比为6:1时(催化剂Ru1Ni6/Al)催化活性最高。催化剂Ru1Ni6/Al在氢气中200 ℃直接还原后的平均转化率与氢气中400 ℃还原后的平均转化率接近,达到了单组分Ru/Al催化剂的1.5倍以上。XPS、XRD、H2-TPR数据表明,Ru与Ni之间发生了较强的相互作用,Ni的加入促进了金属Ru在载体上的分散,提高了催化活性。  相似文献   

10.
The ruthenium(II) complexes (η-R5C5)Ru(CO)2X with R = H, CH3 and X = Cl, Br, I undergo a facile reaction with nitric oxide under UV irradiation to afford ruthenium(IV) nitrosyl derivatives of the general type (η-R5C5)Ru(NO)X2.  相似文献   

11.
Electronic structures of SbCl5.L and SnCl4.L2 complexes were studied by the semiempirical PM3 method. The results were compared with the data from 35Cl NQR and 121Sb NQR studies and Mössbauer spectra.

A good correlation was obtained between the calculated and experimental values of quadrupole coupling constants. The calculated energies of the donor-acceptor bond formation were compared with the degree of electron density transfer. The derived correlation dependences between the above two parameters suggest different properties for cis and trans complexes.  相似文献   


12.
Electronic structures of SbCl5.L and SnCl4.L2 complexes were studied by the semiempirical PM3 method. The results were compared with the data from 35Cl NQR and 121Sb NQR studies and Mössbauer spectra.

A good correlation was obtained between the calculated and experimental values of quadrupole coupling constants. The calculated energies of the donor-acceptor bond formation were compared with the degree of electron density transfer. The derived correlation dependences between the above two parameters suggest different properties for cis and trans complexes.  相似文献   


13.
The ruthenium(II) complex Ru(CO)2(NH2(NH2CH2C6H5)2(Si(C6H5)(CH3)2)I has been prepared by the reaction of Ru(CO)4(Si(C6H5)(CH3)2)I with benzylamine. Two-dimensional homonuclear 1H NMR experiments examine the scalar coupling of the enantiotopic amino and methylene protons of the benzylamine ligand. X-ray analysis of Ru(CO)2(NH2CH2C6H5)2(Si(C6H5)(CH3)2)I·1/3C5H12 (triclinic; P ; a = 14.266(4), b = 15.748(5), c = 20.082(6) Å; = 94.38(3), β = 96.30(2), γ = 101.52(2)°) indicates three crystallographically unique complexes form a clathrate with a pentane guest.  相似文献   

14.
以Al2O3为载体,采用吸附-沉淀法制备一系列Ru-Fe/Al2O3催化剂,并进行了H2-TPR、XRD及XPS表征。以马来酸二甲酯(DMM)催化加氢合成丁二酸二甲酯(DMS)为探针反应,考察了Fe的加入对Ru/Al2O3催化性能的影响。评价结果表明,当Fe/Ru原子比小于2时,催化剂活性变化不大;但Fe/Ru原子比大于或等于2时,催化剂活性明显增加;与Ru/Al2O3催化剂相比,Fe的加入改善了催化剂的高温氧化还原处理稳定性。以甲醇为溶剂,在70℃、1.0 MPa压力、600 r/min转速下,Ru-Fe/Al2O3催化DMM的转化率与生成DMS的选择性均接近100%。XPS和H2-TPR表征结果表明,Ru-Fe/Al2O3中Fe与Ru产生较强的相互作用,促进Ru的分散且调变了Ru的电子特性。  相似文献   

15.
ZnCl_2溶液中微波辅助SnCl_4催化纤维素制备5-HMF   总被引:1,自引:0,他引:1  
将纤维素溶解在ZnCl_2溶液中,以SnCl_4为催化剂,微波下使纤维素降解成5-羟甲基糠醛(5-HMF)。实验考察了微波功率、纤维素的质量、ZnCl_2溶液浓度、反应时间及催化剂与纤维素物质的量比等对5-HMF产率的影响。结果表明,以SnCl_4为催化剂,在优化条件:1.0 g纤维素溶解在100 m L 70%ZnCl_2溶液中,微波功率为420 W,降解反应9 min,SnCl_4与纤维素物质的量比2∶1下,5-HMF的产率达到39.4%。  相似文献   

16.
Addition of 1,4-dithiols to dichloromethane solutions of [PtCl2(P-P)] (P-P = (PPh3)2, Ph2P(CH2)3PPh2, Phd2P(CH2)4PPh2; 1,4-dithiols = HS(CH2)4SH, (−)DIOSH2 (2,3-O-isopropylidene-1,4-dithiol-l-threitol), BINASH2 (1,1′-dinaphthalene-2,2′-dithiol)) in the presence of NEt3 yielded the mononuclear complexes [Pt(1,4-dithiolato)(P-P)]. Related palladium(II) complexes [Pd(dithiolato)(P-P)] (P-P=Ph2P(CH2)3PPh2, Ph2P(CH2)4PPh2; dithiolato = S(CH2)4S, (−)-DIOS) were prepared by the same method. The structure of [Pt((−)DIOS)(PPh3)2] and [Pd(S(CH2)4S)(Ph2P(CH2)3PPh2)] complexes was determined by X-ray diffraction methods. Pt—dithiolato—SnC12 systems are active in the hydroformylation of styrene. At 100 atm and 125°C [Pt(dithiolate)(P-P)]/SnCl2 (Pt:Sn = 20) systems provided aldehyde conversion up to 80%.  相似文献   

17.
Electrocatalytic water oxidation to evolve O2 was studied on a Nafion–RuO2–Ru(bpy)32+ composite electrode. The O2 evolution current efficiency was largely improved for the multi-component electrode over the Nafion–RuO2 and Nafion–Ru(bpy)32+ individuals. The redox mediation through the Ru(bpy)32+ was found to dominate over the RuO2 catalytic effect in the water oxidation mechanism. The specific surface area of the RuO2, which was prepared at different temperatures (300–700°C), used in fabricating the composite electrode also played an important role in the overall water oxidation mechanism. Both the reaction and electrode parameters were optimized to get effective electrocatalytic current values in this study.  相似文献   

18.
19.
The title compounds react with unidentate ligands, L, containing either phosphorus or arsenic donor atoms to yield the corresponding compounds of the type Ru(η5---C5Me4Et)(CO)LX; with didentate phosphorus donor ligands the major species formed is the bridged complex {Ru(η5---C5Me4Et)(CO)X}2{Ph2P(CH2)nPPh 2} n = 1, X = Br; n = 2, X = Cl). In contrast, unidentate ligands containing nitrogen donor atoms such as pyridine did not react with Ru(η5---C5Me4Et)(CO)2Cl although reaction with 1,10-phenanthroline or diethylenetriamine yielded the ionic products [Ru(η5---C5Me4Et)(CO)L]+Cl (L = phen or (NH2CH2CH2)2NH). Reaction of Ru(η5---C5Me4Et)(CO)2Br with AgOAc yielded the corresponding acetato complex Ru(η5---C5Me4Et)(CO)20Ac. Ru(η5--- C5Me4Et)(CO)2X reacts with AgY (Y = BF4 or PF6) in either acetone or dichloromethane to give the useful solvent intermediates [Ru(η5---C5Me4Et)(CO)2(solvent)]+Y, which readily react with ligands L to yield ionic derivatives of the type [Ru(η5---C5Me4Et)(CO)2L]+Y (where L = CO, NCMe, py, C2H4 or MeO2CCCCO2Me).  相似文献   

20.
The new heterobimetallic complex [Mo(μ-Cl)(SnCl3)(CO)34-NBD)] (1) has been prepared by reaction of [(CO)4Mo(μ-Cl)3Mo(SnCl3)(CO)3] with norbornadiene (NBD) at room temperature. The structure of complex 1 was established by X-ray crystallography. The IR, 1H- and 13C-NMR spectra of 1 are also described and can be correlated with the crystallographically observed geometry. In the presence of an excess of NBD compound 1 initiates the ring-opening metathesis polymerisation (ROMP). The initiation mechanism of ROMP by seven-coordinate molybdenum(II) compounds have been discussed. The microstructure of polynorbornadiene formed was determined by 1H- and 13C-NMR spectroscopy.  相似文献   

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