首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 390 毫秒
1.
The reaction of iPr2Si(PH2)2 ( 1 ) with [Ca{N(SiMe3)2}2(THF)2] at 25 °C in molar ratio 1:1 yields the compound [Ca3{iPr2Si(PH)2}3(THF)6] ( 2 ). Compound 2 consists of two Ca2P3 trigonal bipyramids with one conjoint calcium corner and SiiPr2 bridged phosphorus atoms. In contrast, the same reaction at 60 °C yield the complex [Ca({P(SiiPr2)2PH}2(THF)4] ( 3 ). The isotype strontium compound [Sr({P(SiiPr2)2PH}2(THF)4] ( 4 ) was obtained from the reaction of iPr2Si(PH2)2 with [Sr{N(SiMe3)2}2(DME)2]. The Compounds 2 – 4 were characterised by single crystal X‐ray diffraction, elemental analysis as well as IR and NMR spectroscopic techniques.  相似文献   

2.
The reaction of AlCl3 with Li2PR (R = SiiPr3, SiMeiPr2) in a mixture of heptane and ether yields in the polycyclic compounds [(AlCl)43‐PR)2(μ‐PR)2(Et2O)2]( 1a : R = SiiPr3; 1b : SiMeiPr2) with a ladder‐shaped Al4P4 core. The coordination sphere of the outer aluminium atoms in these compounds is completed by ether ligands. In contrast, the reaction of AlCl3 with Li2PSiiPr3 in pure heptane yields in the formation of the hexagonal prismatic compound [(AlCl)63‐PSiiPr3)6]( 2 ). 1 and 2 were characterized by single crystal X‐ray diffraction analysis as well as by 31P{1H} and 27Al NMR spectroscopy. The structure determining effect of the solvent can be rationalized by quantumchemical calculations, which also show that the hexagonal prismatic structure is the most stable of the investigated oligomers in absence of ether.  相似文献   

3.
We report on the synthesis of new derivatives of silylated clusters of the type [Ge9(SiR3)3]? (R = SiMe3, Me = CH3; R = Ph, Ph = C6H5) as well as on their reactivity towards copper and zinc compounds. The silylated cluster compounds were synthesized by heterogeneous reactions starting from the Zintl phase K4Ge9. Reaction of K[Ge9{Si(SiMe3)3}3] with ZnCl2 leads to the already known dimeric compound [Zn(Ge9{Si(SiMe3)3}3)2] ( 1 ), whereas upon the reaction with [ZnCp*2] the coordination of [ZnCp*]+ to the cluster takes place (Cp*=1,2,3,4,5‐pentamethylcyclopentadienyl) under the formation of [ZnCp*(Ge9{Si(SiMe3)3}3)] ( 2 ). A similar reaction leads to [CuPiPr3(Ge9{Si(SiMe3)3}3)] ( 3 ) from [CuPiPr3Cl] (iPr=isopropyl). Further we investigated the novel silylated cluster units [Ge9(SiPh3)3]? ( 4 ) and [Ge9(SiPh3)2]? ( 5 ), which could be identified by mass spectroscopy. Bis‐ and tris‐silylated species can be synthesized by the respective stoichiometric reactions, and the products were characterized by ESI‐MS and NMR experiments. These clusters show rather different reactivity. The reaction of the tris‐silylated anion 4 with [CuPiPr3Cl] leads to [(CuPiPr3)3Ge9(SiPh3)2]+ as shown from NMR experiments and to [(CuPiPr3)4{Ge9(SiPh3)2}2] ( 6 ), which was characterized by single‐crystal X‐ray diffraction. Compound 6 shows a new type of coordination of the Cu atoms to the silylated Zintl clusters.  相似文献   

4.
New GaE and InE Four Membered Ring Compounds: Syntheses and Crystal Structures of [Et2InE(SiMe3)2]2 and [GaCl(P t Bu2Me)E(SiMe3)]2 (E = P, As) Et3In · PR3 (R = Et, iPr) reacts with H2ESiMe3 under liberation of C2H6 and EH3 to form the cyclic compounds [Et2InE(SiMe3)2]2 ( 1 a : E = P, 1 b : E = As). 1 consists of a planar four membered In2E2 ring in which the indium and phosphorus or arsenic atoms are four coordinated. In contrast, the phosphorus/arsenic atoms in [GaCl(PtBu2Me)E(SiMe3)]2 ( 2 a : E = P, 2 b : E = As) only have the coordination number three. 2 results from the reaction of GaCl3 · PtBu2Me with As(SiMe3)3 or Li2PSiMe3 respectively, and displays a folded four membered Ga2E2 ring as central structural motif. 1 and 2 have been characterised by single crystal X‐ray diffraction analysis as well as 1H and 31P{1H} NMR spectroscopy.  相似文献   

5.
Three new complexes with phosphanylphosphido ligands, [Cu4{μ2‐P(SiMe3)‐PtBu}4] ( 1 ), [Ag4{μ2‐P(SiMe3)‐PtBu2}4] ( 2 ) and [Cu{η1‐P(SiMe3)‐PiPr2}2][Li(Diglyme)2]+ ( 3 ) were synthesized and structurally characterized by X‐ray diffraction, NMR spectroscopy, and elemental analysis. Complexes 1 and 2 were obtained in the reactions of lithium derivative of diphosphane tBu2P‐P(SiMe3)Li · 2.7THF with CuCl and [iBu3PAgCl]4, respectively. The X‐ray diffraction analysis revealed that the complexes 1 and 2 present macrocyclic, tetrameric form with Cu4P4 and Ag4P4 core. Complex 3 was prepared in the reaction of CuCl with a different derivative of lithiated diphosphane iPr2P‐P(SiMe3)Li · 2(Diglyme). Surprisingly, the X‐ray analysis of 3 revealed that in this reaction instead of the tetramer the monomeric form, ionic complex [Cu{η1‐P(SiMe3)‐PiPr2}2][Li(Diglyme)2]+ was formed.  相似文献   

6.
Lithium 8‐amidoquinoline ( 1 ) and lithium 8‐(trialkylsilylamido)quinoline [SiMe2tBu ( 2 ), SiiPr3 ( 3 )] react with dimethylgallium chloride to the metathesis products dimethylgallium 8‐amidoquinoline ( 4 ) as well as dimethylgallium 8‐(trialkylsilylamido)quinoline [SiMe2tBu ( 5 ), SiiPr3 ( 6 )]. The gallium atoms are in distorted tetrahedral environments. During the synthesis of 5 , orange dimethylgallium 2‐butyl‐8‐(tert‐butyldimethylsilylamido)quinoline ( 7 ) was found as by‐product. The metathesis reactions of Me2GaCl with LiN(R)CH2Py (Py = 2‐pyridyl) yield the corresponding 2‐pyridylmethylamides Me2Ga‐N(H)CH2Py ( 8 ), Me2Ga‐N(SiMe2tBu)CH2Py ( 9 ) and Me2Ga‐N(SiiPr3)CH2Py ( 10 ). In these complexes the gallium atoms show a distorted tetrahedral coordination sphere. However, derivative 8 crystallizes dimeric with bridging amido units whereas in 9 and 10 the 2‐pyridylmethylamido moieties act as bidentate ligands leading to monomeric molecules.  相似文献   

7.
Five copper zinc phenylchalcogenolate complexes [(iPr3PCu)3(ZnMe2)2(SPh)3] ( 1 ), [(iPr3PCu)2(ZnPh)4(SPh)6] ( 2 ), [(iPr3PCu)2(ZnEt)4(SPh)6] ( 3 ), [(iPr3PCu)3(ZnEt)(SePh)4] ( 4 ), and [(iPr3PCu)3Cu(iPr3PZn)(TePh)6] ( 5 ) were synthesized by the reaction of phosphine stabilized copper phenylchalcogenolate complexes with ZnR2 (R = Me, Et, Ph) with and without additional chalcogenol. The novel mixed metal compounds were characterized by single‐crystal X‐ray structure analysis and NMR spectroscopy. 4 and 5 are the first examples of compounds with a Zn–Se–Cu or a Zn–Te–Cu linkage, respectively.  相似文献   

8.
Reaction of 7‐{(N‐2,6‐R)iminomethyl)}indole ( HL1 , R = dimethylphenyl; HL2 , R = diisopropylphenyl) and rare‐earth metal tris(alkyl)s, Ln(CH2SiMe3)3(THF)2, generated new rare‐earth metal bis(alkyl) complexes LLn(CH2SiMe3)2(THF) [L = L1: Ln = Lu ( 1a ), Sc ( 1b ); L = L2: Ln = Lu ( 3a ), Sc ( 3b )] and mono(alkyl) complexes L22Lu(CH2SiMe3) ( 4a ). Treatment of alkyl complexes 1a and 4a with N,N′‐diisopropylcarbodiimide afforded the corresponding amidinates L1Lu{iPr2NC(CH2SiMe3)NiPr2}2 ( 2a ) and L22Lu{iPr2NC(CH2SiMe3)NiPr2} ( 5a ), respectively. These new rare‐earth metal alkyls and amidinates except 4a in combination with aluminum alkyls and borate generated efficient homogeneous catalysts for the polymerization of isoprene, providing high cis‐1,4 selectivity and high molar mass polyisoprene with narrow molar mass distribution (Mn = 2.65 × 105, Mw/Mn = 1.07, cis‐1,4 98.2%, −60 °C). The environmental hindrance around central metals arising from the bulkiness of the ligands, the Lewis‐acidity of rare‐earth metal ions, the types of aluminum tris(alkyl)s and borate, and polymerization temperature influenced significantly on both the catalytic activity and the regioselectivity. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5251–5262, 2008  相似文献   

9.
tert‐Butyl(dichloromethyl)bis(trimethylsilyl)silane ( 4 ), prepared by the reaction of tert‐butylbis(trimethylsilyl)silane with trichloromethane and potassium tert‐butoxide, reacted with 2,4,6‐triisopropylphenyllithium (TipLi) (molar ratio 1 : 2) at room temperature to give (after hydrolytic workup) the silanol tBu(2,4,6‐iPr3C6H2)Si(OH)–CH(SiMe3)2 ( 15 ). The formation of 15 is discussed as proceeding through the indefinitely stable silene tBu(2,4,6‐iPr3C6H2)Si=C(SiMe3)2 ( 13 ), but attempts to isolate the compound failed. Treatment of (dibromomethyl)ditert‐butyl(trimethylsilyl)silane ( 7 ), made from tBu2(Me3Si)SiH, HCBr3 and KOtBu, with methyllithium (1 : 3) at –78 °C afforded tBu2MeSi–CHMeSiMe3 ( 19 ); 7 and phenyllithium (1 : 3) under similar conditions gave tBu2PhSi–CH2SiMe3 ( 20 ). The reaction paths leading to 15 , 19 and 20 are discussed. Reduction of 7 with lithium in THF produced the substituted ethylene tBu2(Me3Si)SiCH=CHSitBu2SiMe3 ( 21 ). For 21 the results of an X‐ray structural analysis are given.  相似文献   

10.
The reaction of the NHC iPr2Im [NHC=N‐heterocyclic carbene, iPr2Im = 1, 3‐bis(isopropyl)imidazolin‐2‐ylidene] with freshly prepared NiBr2 in thf or dme results in the formation of the air stable nickel(II) complex trans‐[Ni(iPr2Im)2Br2] ( 2 ). Complex 2 was structurally characterized. Thermal analysis (DTA/TG) reveals a very high decomposition temperature of 298 °C. Reduction of 2 with sodium or C8K in the presence of the olefins COD (cyclooctadiene) or COE (cyclooctene) affords the highly reactive compounds [Ni2(iPr2Im)4(COD)] ( 1 ) and [Ni(iPr2Im)2(COE)] ( 4 ). Alkylation of 2 with organolithiums leads to the formation of trans‐[Ni(iPr2Im)2(R)2] [R = Me ( 5 ), CH2SiMe3 ( 6 )], whereas the reaction of 2 with LiCp* [Cp* = (η5‐C5(CH3)5)] at 80 °C causes the loss of one NHC ligand and affords [(η5‐C5(CH3)5)Ni(iPr2Im)Br] ( 7 ).  相似文献   

11.
The Tris(triisopropylsilyl)pnikogenes: Synthesis and Characterisation of [E(Si i Pr3)3] (E = P, As, Sb) The compounds [E(SiiPr3)3] (E = P, As, Sb) ( 1 – 3 ) were prepared in high yields by the reaction of (Na/K)3E with iPr3SiCl in DME. They were characterised by 1H‐, 13C‐, 29Si‐ and 31P‐NMR spectroscopy, mass spectrometry and single crystal X‐ray diffraction. Compound 1 , recently obtained in a different way, shows an unusual trigonal planar coordination of the central phosphorus atom. However, 2 and 3 , featuring increasing covalence radii of the central atoms, show an increasingly pyramidal structure. 1 – 3 crystallise isotyp in the cubic spacegroup Pa 3, the lattice constants are: 1 : a = 1860.1(2) pm, 2 : a = 1873.6(2) pm, 3 : a = 1897.1(2) pm.  相似文献   

12.
Reaction of NaAlH4 with Primer Silylphosphines and Silylarsines: Synthesis and Crystal Structure of a Cyclic Sodium Phosphanylalanate and a Polycyclic Sodium Arsanylalanate The reaction of sodium aluminium hydride with H2PSiMe3 in the molar ratio 1:4 yields the compound [H2Al{P(SiMe3)2}2Na(dme)2] ( 1 ). Central structural motif of this compound in a four‐membered AlP2Na ring. Surprisingly the phosphorus atoms in the ring wear two exocyclic silylgroups each. From the reaction of NaAlH4 with the primer silylarsine H2AsSiiPr3 in THF the ionic compound 2 can be obtained. In this compound cyclic [(H2Al)3(AsSiiPr3)3]3‐ anions coordinate the sodium counter‐ions by the hydride ligands as well as by the arsenic atoms.  相似文献   

13.
Several palladium(II) and platinum(II) complexes of tripropylarsanes (AsR3; R = Pr, iPr) with the formulae, [MCl2(AsR3)2], [M2Cl2(μ‐Cl)2(AsR3)2], [Pd2Me2(μ‐Cl)2(AsR3)2], [Pd2X2(μ‐Pz)2(AsR3)2] (X = Cl or Me, Pz = pyrazolate), [Pd2Cl2(μ‐Y)2(AsR3)2] (Y = OAc or SPh), [MCl(S2CNEt2)(AsR3)] and [PdCp(Cl)(AsiPr3)] (M = Pd or Pt) have been prepared. All the complexes have been characterised by elemental analyses, IR and 1H NMR spectroscopy. The stereochemistry of the complexes has been deduced from the spectroscopic data. The structures of [Pd2Me2(μ‐X)2(AsiPr3)2] (X = Cl or Pz) have been established by single crystal X‐ray diffraction analyses. Both of the complexes have sym‐trans configuration. Strong trans influence of the methyl group is reflected on the Pd—X bond distances.  相似文献   

14.
The synthesis, characterization and ε‐caprolactone polymerization behavior of lanthanide amido complexes stabilized by ferrocene‐containing N‐aryloxo functionalized β‐ketoiminate ligand FcCOCH2C(Me)N(2‐HO‐5‐But‐C6H3) (LH2, Fc = ferrocenyl) are described. The lanthanide amido complexes [LLnN(SiMe3)2(THF)]2 [Ln = Nd ( 1 ), Sm ( 2 ), Yb ( 3 ), Y ( 4 )] were synthesized in good yields by the amine elimination reactions of LH2 with Ln[N(SiMe3)2]3(µ‐Cl)Li(THF)3 in a 1:1 molar ratio in THF. These complexes were characterized by IR spectroscopy and elemental analysis, and 1H NMR spectroscopy was added for the analysis of complex 4 . The definitive molecular structures of complexes 1 and 3 were determined by X‐ray diffraction studies. Complexes 1 – 4 can initiate the ring‐opening polymerization of ε‐caprolactone with moderate activity. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

15.
The synthesis and characterization of dimeric lanthanide amides stabilized by a dianionic N‐aryloxo functionalized β‐ketoiminate ligand are described in this paper. Reactions of 4‐(2‐hydroxy‐5‐tert‐butyl‐phenyl)imino‐2‐pentanone (LH2) with Ln[N(SiMe3)2]3(µ‐Cl)Li(THF)3 in a 1:1 molar ratio in THF gave the dimeric lanthanide amido complexes [LLn{N(SiMe3)2}(THF)]2 [Ln=Nd ( 1 ), Sm ( 2 ), Yb ( 3 ), Y ( 4 )] in good isolated yields. These complexes were characterized by IR spectroscopy, elemental analysis, and 1H NMR spectroscopy in the case of complex 4 . The definitive molecular structures of complexes 1 , 3 , and 4 were determined. It was found that complexes 1 to 4 can initiate the ring‐opening polymerization of L‐lactide.  相似文献   

16.
Tris(iso‐propyl)stibine complexes of palladium and platinum of the type [MX2(SbiPr3)2] [M, X = Pd, Cl (1a), Pd, Br (1b), Pd, I (1c), Pt, Cl (2)] have been prepared and characterized by elemental analysis, IR and 1H NMR spectral data. The structure of 1a, established by X‐ray structural analysis, revealed that the palladium atom is in a square planar environment with mutually trans SbiPr3 ligands. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

17.
Reactions of 1,3-diisopropylcarbodiimide with alkali metal amides, MN(SiMe3)2 (M=Li or Na) in hexane or THF produced the alkali metal guanidinates { (i-PrN)2C [N(SiMe3)2]Li }2 (1) and { (i-PrN)2C[N(SiMe3)2]Na(THF) } 2 (2) in nearly quantitative yields. Both complexes 1 and 2 were well characterized by elemental analysis, IR spectra, ^1H and ^13C NMR spectra, and X-ray diffraction. It was found that the guanidinates adopt different coordination modes in these complexes.  相似文献   

18.
1,4‐Di(isopropyl)‐1,4‐diazabutadiene as a Reagent for the Trapping of Monomeric Fragments of the Tetragalliumcluster Ga4[C(SiMe3)3]4 – Formation of an Unsaturated GaN2C2 Heterocycle and an Oxidation Product Containing a Ga‐O‐O‐Ga Group The tetrahedral tetragallium cluster Ga4[C(SiMe3)3]4 ( 1 ) dissociates upon dissolution to yield the monomeric fragments Ga‐R [R = C(SiMe3)3]. These monomers could be trapped now by the treatment of their solutions with 1,4‐di(isopropyl)‐1,4‐diazabutadiene. The product of the cycloaddition reaction ( 2 ) possesses a five‐membered GaN2C2 heterocycle with a coordinatively unsaturated gallium atom and an endocyclic C=C double bond. 2 is rather sensitive towards oxidation by traces of air. The contact with oxygen yielded a digallium peroxide [(C2N2iPr2)RGa‐O‐O‐GaR(C2N2iPr2)] ( 3 ) which was isolated in a very low yield only and which has a gallium atom attached to each oxygen atom of the inner peroxo group. Both chelating ligands of 3 possess an unpaired electron.  相似文献   

19.
Nanosheet compounds Pd11(SiiPr)2(SiiPr2)4(CNtBu)10 ( 1 ) and Pd11(SiiPr)2(SiiPr2)4(CNMes)10 ( 2 ), containing two Pd7(SiiPr)(SiiPr2)2(CNR)4 plates (R=tBu or Mes) connected with three common Pd atoms, were investigated with DFT method. All Pd atoms are somewhat positively charged and the electron density is accumulated between the Pd and Si atoms, indicating that a charge transfer (CT) occurs from the Pd to the Si atoms of the SiMe2 and SiMe groups. Negative regions of the Laplacian of the electron density were found between the Pd and Si atoms. A model of a seven‐coordinated Si species, that is, Pd5(Pd?SiMe), is predicted to be a stable pentagonal bipyramidal molecule. Five Pd atoms in the equatorial plane form bonding overlaps with two 3p orbitals of the Si atom. This is a new type of hypervalency. The Ge analogues have geometry and an electronic structure similar to those of the Si compounds. But their formation energies are smaller than those of the Si analogues. The use of the element Si is crucial to synthesize these nanoplate compounds.  相似文献   

20.
Five coordination compounds of bismuth, lanthanum and praseodymium nitrate with the oxygen‐coordinating chelate ligand (iPrO)2(O)PCH2P(O)(OiPr)2 (L) are reported: [Bi(NO3)3(L)2] ( 1 ), [La(NO3)3(L)2] ( 2 ), [Pr(NO3)3(L)2] ( 3 ), [La(NO3)3(L)(H2O)] ( 4 ) and [Pr(NO3)3(L)(H2O)] ( 5 ). The compounds were characterized by means of single crystal X‐ray crystallography, 1H and 31P NMR spectroscopy in solution, solid‐state 31P NMR spectroscopy, IR spectroscopy, DTA‐TG measurements ( 1 , 2 and 4 ), conductometry and electrospray ionization mass spectrometry (ESI‐MS). In addition, DFT calculations for model compounds of 1 and 2 support our experimental work. In the solid state mononuclear coordination compounds were observed for 1 — 3 , whereas compounds 4 and 5 gave one‐dimensional hydrogen‐bonded polymers via water‐nitrate coordination. Despite of the similar ionic radii of bismuth(III), lanthanum(III) and praseodymium(III) for a given coordination number the bismuth and lanthanide compounds 1 — 3 are not isostructural. The bismuth compound 1 shows a 9‐coordinate bismuth atom whereas lanthanum(III) and praseodymium(III) atoms are 10‐coordinate in the lanthanide complexes 2 — 5 . The general LnO10 coordination motif in compounds 2 — 5 is best described as a distorted bi‐capped square antiprism. The BiO9 polyhedron might be deduced from the LnO10 polyhedron by replacing one oxygen ligand with a stereochemically active lone pair. The one‐to‐one complexes 4 and 5 dissociate in solution to give the corresponding one‐to‐two complexes 2 and 3 , respectively, and solvated Ln(NO3)3. In contrast to the lanthanides, the one‐to‐two bismuth complex 1 is less stable in CH3CN solution and partially dissociates to give solvated Bi(NO3)3 and (iPrO)2(O)PCH2P(O)(OiPr)2.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号