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1.
1 INTRODUCTION The coordination chemistry of the nitrogen-contai- ning diphosphine ligand bis(diphenylphosphino)ami- ne (Ph2PNHPPh2) has recently received much atten- tion because the P atoms can bridge metal centers in μ-bonding mode to form bi- or polynuclear complex- es[1~10]. It has been shown that the acidity of N–H proton would promote functionalization on the ligand backbone[4, 5, 11]. Although a few complexes contain- ing deprotonated tridentate Ph2PNPPh2 have been synthesi…  相似文献   

2.
采用NMR方法考察了室温和低温(-78~60℃)下Pd2X2(dpm)2(X=NCO-,CH3CO2-,SCN-和NO3-,dpm=Ph2PCH2PPh2)与H2S在CD2Cl2或CDCl3中的反应。结果表明,在X=NCO-和CH3CO2-的情况下,H2S优先与这些Pd配合物的阴离子作用生成相应的共轭酸HX和Pd2(SH)2(dpm)2,后者在H2S存在下又进一步转化为Pd2(SH)2(dpm)2(μ-S);当X=SCN-和NO3-时,反应则生成结构可能为[Pd2(H)(SH)(μ-SH)(dpm)2]+的双核Pd配合物。  相似文献   

3.
The chelate complexes of the types (1) and (2) have been synthesized and characterized by IR and NMR spectroscopy. The lower shift of the ν(P-Se) bands and downfield shift of the 31P-{1H}NMR signals for both P(III) and P(V) atoms in 1 and 2 compared to the corresponding free ligands indicate chelate formation through selenium donor. 1 and 2 show terminal ν(CO) bands at 1977 and 1981 cm−1, respectively, suggesting high electron density at the metal center. The molecular structure of 2 has been determined by single-crystal X-ray diffraction. The rhodium atom is at the center of a square planar geometry having the phosphorus and selenium atoms of the chelating ligand at cis-position, one carbonyl group trans- to selenium and one chlorine atom trans- to phosphorus atom. 1 and 2 undergo oxidative addition (OA) reaction with CH3I to produce acyl complexes (3) and (4), respectively. The kinetics of the OA reactions reveal that 1 undergoes faster reaction by about 4.5 times than 2. The catalytic activity of 1 and 2 in carbonylation of methanol was higher than that of the well known species [Rh(CO)2I2] and 2 shows higher catalytic activity compared to 1.  相似文献   

4.
Bis(amino)silane bearing bulky substituents on nitrogen, LH2 [L = Me2Si(NDipp)2, Dipp = 2, 6‐diisopropylphenyl] was reacted with nBuLi (ratio 1:1 and 1:2) in toluene. The Me2Si(LiNDipp)2 was treated with SbCl3 in a 1:1 ratio to yield the four‐membered SiN2Sb ring compound of composition [η2(N,N)‐Me2Si(NDipp)2SbCl] ( 1 ). The mono lithiated bis(amino)silane was used to synthesize the monodentate heterotetraatomic complex [(η1‐Me2SiNDipp)NHDippSbCl2] ( 2 ) by the reaction with SbCl3. The complexes were characterized by 1H and 13C NMR, elemental analysis, IR, and single‐crystal X‐ray structural analysis.  相似文献   

5.
1 INTRODUCTION Recently coinage metal complexes of poly- dentate phosphines are of great interest owing to the applications in diverse areas such as supramolecular design, photophysics and catalysis[1~4]. It is well- known that the binuclear coinage metal complexes of diphosphine [M2(diphosphine)2(MeCN)2]2+ (M = Cu, Ag, Au)[5~16] are excellent precursors for the design of polynuclear or polymeric materials with desired properties due to the easy substitution of weakly coordinated ac…  相似文献   

6.
手性二噁唑啉吡啶铁和镍配合物的制备与表征   总被引:1,自引:0,他引:1  
Tridentate bis(oxazolinylpyridine)(1) reacted with nickel chloride or ferrous chloride in anhydrous ethanol to form bis(oxazolinylpyridine) Nickel(Ⅱ) and Iron(Ⅱ) complexes. The stable solid complexes were characterized with IR, UV, MS, XPS and elemental analysis. No stable complexes were formed with bidentate bis(oxazoline)(2) ins- tead of bis(oxazolinylpyridine).  相似文献   

7.
4,4′-Bis(methylene)biphenylene bridged homodinuclear titanocene (3) and zirconocene (4) have been synthesized by treatment of CpTiCl3 and CpZrCl3 · DME with Na2[C5H4CH2C6H4-p-C6H4CH2C5H4], respectively, in THF and characterized by 1H NMR and element analysis. After activation with methyl aluminoxane (MAO), these catalysts were used for the homogeneous polymerization of ethylene. The influences of reaction conditions, such as temperature, time, catalyst concentration and molar ratio of MAO/Cat. on ethylene polymerization were investigated in detail. The catalytic activities of 3 and 4 are more than three times higher than that of the phenyldimethylene bridged homodinuclear metallocene of titanocene (5) and zirconocene (6), respectively, and also twice higher than that of Cp2TiCl2/MAO and Cp2ZrCl2/MAO, respectively. However, the catalytic activity of 3 is nearly half as high as that of 4, which reached 1.31 × 106 g PE/mol cat h. The molecular weight of polyethylene increases simultaneously with prolongation of polymerization time. GPC spectra show that 3 and 4 produce polyethylene with broad molecular weight distribution (4.28 and 3.18). The high melting points of the products (131-134 °C) indicate that the polyethylene formed is highly linear and highly crystalline.  相似文献   

8.
Treatment of Co4(CO)12 with an excess of trimethylsilylacetylene (TMSA) in the presence of tri(2‐thienyl)phosphine in THF at 25 °C for 2 hours yielded six compounds. Two pseudo‐octahedral, alkyne‐bridged tetracobalt clusters, [Co44‐η2‐HC≡CSiMe3)(CO)10(μ‐CO)2] ( 4 ) and [Co44‐η2‐HC≡CSiMe3)‐(CO)9(μ‐CO)2{P(C4H4S)3}] ( 6 ), along with an alkyne‐bridged dicobalt complex, [Co2(CO)5(μ‐HC≡CSiMe3)‐{P(C4H4S)3}] ( 5 ), were obtained as new compounds. The addition of the thienylphosphine ligand, in fact, facilitates the reaction rate. Reaction of an alkyne‐bridged dicobalt complex, [(η2‐H‐C≡C‐SiMe3)Co2(CO)6] ( 3 ), with a bi‐functional ligand, PPh(‐C≡C‐SiMe3)2, yielded an unexpected six‐membered, cyclic compound, {(Ph)(Me3Si‐C≡C)P‐[(η2‐C≡C‐SiMe3)Co2(CO)5]}2 ( 7 ). All of these new compounds were characterized by spectroscopic means; the solid‐state structures of ( 5 ), ( 6 ) and ( 7 ) have been established by X‐ray crystallography.  相似文献   

9.
Complexes of the type [Pt R2 (dppma-PP′)] (R─Me, Et, Ph, CH2Ph, C6H4 Me-p, C6H4OMe-2, CH2CMe3, 1-naphthyl, C6H4Me-o, dppma = Ph2PNMe PPh2) have been prepared from [PtCl2, (dppma-PP′)] and the corresponding alkyl-lithium or Grignard reagents. Equilibrium constants, k, for the conversion of [PtR2 (dppma-PP′)] into cis-[PtR2(dppma-P)2] with dppma were studied using 31P NMR spectroscopy at room temperature. Equilibrium is rapidly established for R─C6H4-Me-o, at 20°C. Complex of the type cis-[PtR2 (dppma-P)2] was isolated R─C6H4 Me-o. The complexes [PtMe2(dppma-P)2] and [Pt(o-methoxyphenyl)2(dppma-P)2] were prepared, but unfortunately decomposed once isolated, the only evidence for its formation being from 31P-{1H} NMZR spectroscopy. The o-tolyl or 1-naphthyl complexes exist as syn-anti mixtures in solution, due to restricted rotation around the platinum aryl bonds. Treatment of several complexes of the type [PtR2(dppma-PP′)] with MeI gives [PtR2Me(I)(dppma-PP′)] with trans addition of MeI. Treatment of [PtR2(dppma-PP′)] with HCl gives [Pt Cl (R) (dppma-PP′)] for R─C6H2Me3-2,4,6, C6H4-CH3-2, C6H4-Me-4, Me, 1-naphthyl. The 1H, 31P NMR parameters for these complexes are discussed. Attempted preparation of complexes of the type [PtR2 (dppma-P)2M] (R─C6H4-Me-2, Me CN-C6H4-Me-4); M─Pd, Pt, Au,) are reported.  相似文献   

10.
A systematic study was conducted on the Cr catalysed tri- and tetramerisation of ethylene using bis(diphenylphosphino)amine ligands with N-aryl functionality. This study revealed that the oligomerisation reaction product selectivity is primarily dependent on the structure and size of the N-aryl groups.

Addition of sufficient steric bulk to the N-phenyl group via ortho-alkyl substitution increased the combined 1-hexene and 1-octene selectivity (overall alpha selectivity) to above 82% at an overall 1-octene selectivity of 56%. The introduction of a single carbon spacer between the N-atom and the aryl-moiety, as well as the addition of branching on this carbon, resulted in further selectivity improvements, achieving an overall 1-octene selectivity of 64% and an overall alpha selectivity of 84%. This was obtained at catalyst productivities in excess of 1,000,000 g/g Cr/h.  相似文献   


11.
无水三氯化稀土(LnCl3),二(三甲硅基)胺基钾(LiN(SiMe3)2〗及1-(2-甲乙基)茚室温上在四氢呋喃溶剂中反应,得到了4个含1-(2-甲氧乙基)茚基和二(三甲硅基)胺基的稀土金属有机物{(C9H6CH2C2OMe)Ln〖N(SiMe3)2〗2(Ln=Nd,Sm,Dy,Yb)},这些配合物均经元素分析、IR和MS表征。  相似文献   

12.
EPR and spectrophotometric study on the products of ligand‐exchange taking place on mixing bis(diethyldiselenocarbamato)copper(II), [Cu(Et2dsc)2], and bis(diethyldithiocarbamato)copper(II), [Cu(Et2dtc)2], solutions is reported. EPR spectra monitored at room temperature for one month period reveal a stable equilibrium among the parents (chromophores CuS4 and CuSe4) and the obtained mixed‐chelate [Cu(Et2dtc)(Et2dsc)] complex (chromophore CuS2Se2) in heptane, hexane, benzene, toluene, acetone, DMFA, DMSO and dichloromethane. In CCl4 and CHCl3 two new additional EPR spectra appear attributed to the mixed‐chelate complexes with the chromophores CuSSe3 and CuS3Se which are not observed with electronic spectroscopy. The intensities of all five EPR spectra decrease with the time. It is assumed that the new mixed‐chelates observed in CCl4 and CHCl3 are obtained in a reaction of [Cu(Et2dtc)(Et2dsc)] or [Cu(Et2dtc)2] with the ester of diselenocarbamic acid which is formed in a parallel reaction of [Cu(dsc)2]with CCl4 or CHCl3.  相似文献   

13.
Two new copper(II) complexes of saccharinate (sac) with bis(2‐pyridylmethyl)amine (bpma) and N,N′‐bis[1‐(pyridin‐2‐yl)ethylidene]ethane‐1,2‐diamine (bapen), [Cu(bpma)(sac)2] · H2O ( 1 ) and [Cu(bapen)(sac)2] ( 2 ), were synthesized and characterized by elemental analysis, TG‐DTA, X‐ray diffraction, and UV/Vis and IR spectroscopy, respectively. In 1 , the copper(II) ion is coordinated by two N‐bonded sac ligands, and three nitrogen atoms of bpma, in a distorted square‐pyramidal coordination arrangement, whereas the arrangement around the copper ion in 2 is a distorted octahedron with two N‐coordinated sac ligands and a tetradentate bapen ligand. In addition to hydrogen bonding involving the water molecule in 1 , the mononuclear species of 1 and 2 are further connected by weak intermolecular C–H ··· π and C–H ··· O interactions to form a three‐dimensional network. Both complexes are luminescent at room temperature and their emissions seem to be due to ligand‐based π–π* transitions.  相似文献   

14.
Reactions of bis(phosphinimino)methanes H2C(PPh2NR)2 [R = SiMe3 (L1H), Ph (L2H), 2,6‐iPr2‐C6H3 (DIPP) (L3H)] with ZnR2 (R = Me, Et) yielded the corresponding bis(phosphinimino)methanide zinc complexes LZnMe [L2 ( 1 ), L3 ( 2 )] and LZnEt [L1 ( 3 ), L2 ( 4 ), and L3 ( 5 )]. Complexes 1 – 5 were characterized by heteronuclear NMR (1H, 13C, 31P) and IR spectroscopy, elemental analysis, and single‐crystal X‐ray diffraction.  相似文献   

15.
Two dinuclear succinato‐bridged nickel(II) complexes [Ni(RR‐L)]2(μ‐SA)(ClO4)2 ( 1 ) and [Ni(SS‐L)]2(μ‐SA)(ClO4)2 ( 2 ) (L = 5, 5, 7, 12, 12, 14‐hexamethyl‐1, 4, 8, 11‐tetraazacyclotetradecane, SA = succinic acid) were synthesized and characterized by EA, Circular dichroism (CD), as well as IR and UV/Vis spectroscopy. Single crystal X‐ray diffraction analyses revealed that the NiII atoms display a distorted octahedral coordination arrangement, and the succinato ligand bridges two central NiII atoms in a bis bidentate fashion to form dimers in 1 and 2 . The monomers of {[Ni(RR‐L)]2(μ‐SA)}2+ and {[Ni(SS‐L)]2(μ‐SA)}2+ are connected by O–H ··· O and N–H ··· O hydrogen bonds into a 1D right‐handed and left‐handed helical chain along the b axis, respectively. The homochiral natures of 1 and 2 are confirmed by the results of CD spectroscopy.  相似文献   

16.
Syntheses and structures of five imido‐bridged dinuclear titanium complexes and two (bis)ligand‐coordinated mononuclear titanium complexes are reported. Addition of 1 or 2 equiv. of Schiff base ligand (((1H‐pyrrol‐2‐yl)methylene)amino)‐2,3‐dihydro‐1H‐inden‐2‐ol (H2L) to Ti(NMe2)4 resulted in transamination with 4 equiv. of dimethylamides generating a (bis)ligand‐coordinated complex Ti(L)2 ( 1 ). Treatment of Ti(NMe2)4 with 1 equiv. of tBuNH2 followed by addition of 1 equiv. of H2L afforded an imido‐bridged complex [Ti(L)(NtBu)]2 ( 2 ). 1:1:1:1 reaction of Ti(NMe2)4/RNH2/H2L/py(or phen) produced imido‐bridgedcomplexes [Ti(L)(NPh)(py)]2 ( 3 ), [Ti(L)(4‐F‐PhN)(py)]2·Tol ( 4 ·Tol), [Ti(L)(4‐Cl‐PhN)(py)]2·Tol·THF ( 5 ·Tol·THF), [Ti(L)(4‐Br‐PhN)(py)]2·Tol ( 6 ·Tol) and a (bis)ligand‐coordinated complex Ti(L)2·phen ( 7 ) (py = pyridine, phen = 1,10‐phenanthroline). Attempts to prepare the monomeric titianium imido complexes were unsuccessful. DFT studies show that the assumed compound which contains Ti = N species is less stable than imido‐bridged Ti‐N(R)‐Ti complexes, providing the better understanding of the experimental results.  相似文献   

17.
A series of novel rare earth complexes with 11-tungstoferrate as ligand, K15Ln(FeW11 O39)2 .xH2O(Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Er or Yb) were prepared and characterized by elemental analyses, IR, UV-vis, polarograms, magnetic susceptibility and thermal measurement.Keywords Heteropoly complex, Rare earth complex, Synthesis, Bis(undecatungstoferrate) lanthanates of potassium  相似文献   

18.
Planar nickel(II) complexes involving N‐(2‐Hydroxyethyl)‐N‐methyldithiocarbamate, such as [NiX(nmedtc)(PPh3)] (X = Cl, NCS; PPh3 = triphenylphosphine), and [Ni(nmedtc)(P‐P)]ClO4(P‐P = 1,1‐bis(diphenylphosphino)methane(dppm); 1,3‐bis(diphenylphosphino)propane (1,3‐dppp); 1,4‐bis(diphenylphosphino)butane(1,4‐dppb) have been synthesized. The complexes have been characterized by elemental analyses, IR and electronic spectroscopies. The increased νC–N value in all the complexes is due to the mesomeric drift of electrons from the dithiocarbamate ligands to the metal atom. Single crystal X‐ray structure of [Ni(nmedtc)(1,3‐dppp)]ClO4·H2O is reported. In the present 1,3‐dppp chelate, the P–Ni–P angle is higher than that found in 1,2‐bis(diphenylphosphino)ethane‐nickel chelates and lower than 1,4‐bis(diphenylphosphino)butane‐nickel chelates, as a result of presence of the flexible propyl back bone connecting the two phosphorus atoms of the complex.  相似文献   

19.
杨绳岩  吴振奕 《应用化学》2011,28(3):272-277
采用配体取代法合成了以双二苯基膦戊烷(dpppe)及C60为配体、Pt为中心金属的C60Pt(dpppe)新型富勒烯膦金属配合物。 运用质谱、元素分析、紫外-可见吸收光谱、红外吸收光谱和光电子能谱等测试技术对产物进行了表征,同时采用循环伏安法对目标产物进行氧化还原性能研究。 结果表明,C60与金属Pt配位后还原电位发生负移。 结合电子光谱数据确定了目标产物的能级结构,其最高占有轨道和最低非占轨道能级分别为5.635和3.815 eV。 还考察了目标产物在光化学电池中的光伏效应,测试结果表明,在 BQ/H2Q介质溶液中镀层厚度为 1~2 μm 时,具有较好的光电转换性能,光生电压值最高达358 mV。  相似文献   

20.
合成了一系列吡啶双亚胺酰氯三齿Ni(Ⅱ) 配合物(1a~1c, 2a~2c), 通过傅里叶变换红外光谱和元素分析对配合物进行表征, 测定了配合物1a~1c的晶体结构. 3个化合物同属于单斜晶系, 且都具有以Ni原子为中心的近似于Cs对称的扭曲三角双锥构型. 该系列配合物通过倍半乙基氯化铝(EASC)活化, 在20 ℃下对丁二烯聚合表现出良好的催化活性, 得到分子量为4700~5200、 cis-1,4含量为74.8%~77.2%(摩尔分数)的液体聚丁二烯. 通过改变配体的结构和聚合条件, 可在一定范围内调控聚丁二烯的结构和分子量.  相似文献   

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