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1.
Niobium and Tantalum Complexes with P2 and P4 Ligands The photolysis of [Cp″Ta(CO)4] 1 (Cp″ = C5H3tBu2?1,3) and P4 affords Cp″(CO)2Ta(η4?P4) 2 , [{Cp″(CO)Ta}2(m??η2:2?P2)2] 3 and [Cp3″(CO)3Ta3(P2)2] 4 . In a photochemical reaction 2 and [Cp*Nb(CO)4] 5 form [{Cp*(CO)Nb}{Cp″(CO)Ta}(m??η2:2?P2)2] 6 and [{Cp*(CO)2Nb} {Cp*Nb}{Cp″(CO)Ta}(m?32:1:1?P2)2] 7 , a compound with the novel m?32:2:1?P2-coordination mode. The reaction of 2 and [Cp*Co(C2H4)2] 8 leads to [{Cp*Co} {Cp″(CO)Ta}(m??η2:2?P2)2] 9 , a heteronuclear complex with an ?early”? and a ?late”? transition metal. Complexes 2, 3, 7 and 9 have been further characterized by X-ray structure analyses.  相似文献   

2.
Dinuclear Iron Complexes with Different P4 Ligands The photolysis of [Cp″Fe(CO)2]2 1 (Cp″ = C5H3tBu2-1,3) and P4 gives with successive cleavage of P? P bonds and decarbonylation the P4 complex series [Cp″2Fe2P4(CO)4 ? n] 2 (n = O), 3 (n = 1), 4 (n = 2), 5 (n = 3) and 6 (n = 4) with different P4 ligands. 4 and 6 have been further characterized by X-ray structure analyses.  相似文献   

3.
The reaction of either Li2PPh or Li2AsPh with the diborane(4) derivative B2(NMe2)2Br2 affords the compounds [PhP(BNMe2)2]2 ( 1 ) or [PhAs(BNMe2)2]2 ( 2 ) in good yield. Both 1 and 2 have cyclic structures featuring non-planar P2B4 or As2B4 six-membered rings which have chair configurations. Although all four borons in each ring have planar coordination, the two phosphorus or arsenic centers have different degrees of pyramidalization. Bond distances within the rings indicate that the B? B, B? P or B? As bonds are single, whereas the exo-B? N bond lengths are consistent with significant π-bonding. The ring structures of 1 and 2 are in sharp contrast to the related boron-nitrogen species (t-BuN)2N4Me4 which has a nido-N2B4 framework. The attempted synthesis of the nitrogen analogue of 1 or 2 by using a similar approach did not result in the isolation of [PhN(BNMe2)2]2, instead the tetramino diborane(4) species [B(NMe2)NHPh]2 ( 3 ), which has a structure similar to other tetramine diborane(4) compounds, was isolated.  相似文献   

4.
Alternative Ligands. XXV. New Chelating Ligands of the Type Me2ESiMe2(CH2)2E′Me2 (E=P, As; E′=N, P, As) Chelating ligands of the type Me2EsiMe2(CH2)2E′ Me2, have been prepared by the following routes: Starting from Me2Si(Vi)Cl, the compounds with E=N and E′ =N ( 1 ), P ( 2 ), As ( 3 ) are obtained in yields of 65 to 78% by aminolysis to yield Me2NSiMe2Vi, followed by the LiE′ Me2 catalyzed addition of He′Me2 to the vinyl group. The intermediates ClSiMe2(CH2)E′Me2 [E′=N ( 4 ), P ( 5 ), As ( 6 )] are produced by the reactions of 1 to 3 with PhPCl2. 5 and 6 can be prepared in a purer form by the photochemical addition of HPMe2 and HAsMe2, respectively, to the vinyl group of Me2Si(Vo)Cl. 4 to 6 react with LiEMe2, in situ prepared from n-BuLi and HEMe2, to yield the ligands Me2ESiMe2(CH2)2E′Me2 ( 7–12 ) (E=P, As; E′=N, P, As). The new compounds have been characterized by analytical and spectroscopic investigations (NMR, MS).  相似文献   

5.
One‐pot reactions of 2, 6‐bis(acetobenzoyl)pyridine (H2L) with a mixture of LnCl3 (Ln = Ce, Gd) and Ni(CH3COO)2 (ratio 2:1:2) in CH2Cl2/MeOH in the presence of a supporting base like Et3N give trinuclear complexes with the general composition [Ni2Ln(L)2(CH3COO)3(MeOH)2/3] ( 1 ) in high yields. Trinuclear [Ni2Ln(L)2(PhCOO)3(MeOH)2] ( 2 ) complexes are formed when similar reactions are performed starting from NiCl2, and benzoic acid (PhCOOH) is added subsequently. Under the same conditions, reactions with the corresponding cobalt(II) salts result in the formation of a neutral [Co83‐O)2(L)6] complex, which has a bis(triple‐helical) structure. The cobalt(II) analogues to compounds 1 and 2 , however, can be synthesized by a pre‐treatment of the lanthanide salts with H2L and subsequent addition of the cobalt salts, and benzoic acid (in the case of 2 ).  相似文献   

6.
The use of [Cp′′2Zr(η1:1-E4)] (E=P ( 1 a ), As ( 1 b ), Cp′′=1,3-di-tert-butyl-cyclopentadienyl) as phosphorus or arsenic source, respectively, gives access to novel stable polypnictogen transition metal complexes at ambient temperatures. The reaction of 1 a/1 b with [CpRNiBr]2 (CpR=CpBn (1,2,3,4,5-pentabenzyl-cyclopentadienyl), Cp′′′ (1,2,4-tri-tert-butyl-cyclopentadienyl)) was studied, to yield novel complexes depending on steric effects and stoichiometric ratios. Besides the transfer of the complete En unit, a degradation as well as aggregation can be observed. Thus, the prismane derivatives [(Cp′′′Ni)2(μ,η3:3-E4)] ( 2 a (E=P); 2 b (E=As)) or the arsenic containing cubane [(Cp′′′Ni)33-As)(As4)] ( 5 ) are formed. Furthermore, the bromine bridged cubanes of the type [(CpRNi)3{Ni(μ-Br)}(μ3-E)4]2 (CpR=Cp′′′: 6 a (E=P), 6 b (E=As), CpR=CpBn: 8 a (E=P), 8 b (E=As)) can be isolated. Here, a stepwise transfer of En units is possible, with a cyclo-E42− ligand being introduced and unprecedented triple-decker compounds of the type [{(CpRNi)3Ni(μ3-E)4}2(μ,η4:4-E′4)] (CpR=CpBn, Cp′′′; E/E′=P, As) are obtained.  相似文献   

7.
The coordination properties of new types of bidentate phosphane and arsane ligands with a narrow bite angle are reported. The reactions of [{Cp′′′Fe(CO)2}2(μ,η1:1‐P4)] ( 1 a ) with the copper salt [Cu(CH3CN)4][BF4] leads, depending on the stoichiometry, to the formation of the spiro compound [{{Cp′′′Fe(CO)2}231:1:1:1‐P4)}2Cu]+[BF4]? ( 2 ) or the monoadduct [{Cp′′′Fe(CO)2}231:1:2‐P4){Cu(MeCN)}]+[BF4]? ( 3 ). Similarly, the arsane ligand [{Cp′′′Fe(CO)2}2(μ,η1:1‐As4)] ( 1 b ) reacts with [Cu(CH3CN)4][BF4] to give [{{Cp′′′Fe(CO)2}231:1:1:1‐As4)}2Cu]+[BF4]? ( 5 ). Protonation of 1 a occurs at the “wing tip” phosphorus atoms, which is in line with the results of DFT calculations. The compounds are characterized by spectroscopic methods (heteronuclear NMR spectroscopy and IR spectrometry) and by single‐crystal X‐ray diffraction studies.  相似文献   

8.
The reaction of [Cp2Mo2(CO)4(μ,η2:2-E2)] ( A : E=P, B : E=As, Cp=C5H5) with the WCA-containing CuI salts ([Cu(CH3CN)4][Al{OC(CF3)3}4] (CuTEF, C ), [Cu(CH3CN)4][BF4] ( D ) and [Cu(CH3CN)3.5][FAl{OC6F10(C6F5)}3] (CuFAl, E )) affords seven unprecedented coordination compounds. Depending on the E2 ligand complex, the counter anion of the copper salt and the stoichiometry, four dinuclear copper dimers and three trinuclear copper compounds are accessible. The latter complexes reveal first linear Cu3 arrays linked by E2 units (E=P, As) coordinated in an η2:1:1 coordination mode. All compounds were characterized by X-ray crystallography, NMR and IR spectroscopy, mass spectrometry and elemental analysis. To define the nature of the Cu⋅⋅⋅Cu⋅⋅⋅Cu interactions, DFT calculations were performed.  相似文献   

9.
In a high‐yield one‐pot synthesis, the reactions of [Cp*M(η5‐P5)] (M=Fe ( 1 ), Ru ( 2 )) with I2 resulted in the selective formation of [Cp*MP6I6]+ salts ( 3 , 4 ). The products comprise unprecedented all‐cis tripodal triphosphino‐cyclotriphosphine ligands. The iodination of [Cp*Fe(η5‐As5)] ( 6 ) gave, in addition to [Fe(CH3CN)6]2+ salts of the rare [As6I8]2? (in 7 ) and [As4I14]2? (in 8 ) anions, the first di‐cationic Fe‐As triple decker complex [(Cp*Fe)2(μ,η5:5‐As5)][As6I8] ( 9 ). In contrast, the iodination of [Cp*Ru(η5‐As5)] ( 10 ) did not result in the full cleavage of the M?As bonds. Instead, a number of dinuclear complexes were obtained: [(Cp*Ru)2(μ,η5:5‐As5)][As6I8]0.5 ( 11 ) represents the first Ru‐As5 triple decker complex, thus completing the series of monocationic complexes [(CpRM)2(μ,η5:5‐E5)]+ (M=Fe, Ru; E=P, As). [(Cp*Ru)2As8I6] ( 12 ) crystallizes as a racemic mixture of both enantiomers, while [(Cp*Ru)2As4I4] ( 13 ) crystallizes as a symmetric and an asymmetric isomer and features a unique tetramer of {AsI} arsinidene units as a middle deck.  相似文献   

10.
To investigate the influence of P/As substitution on structures and electrical properties, e.g. the effect on material densities, two new solid P/As‐doped solutions, Na2CoP1.60As0.40O7 (disodium cobalt diphosphorus arsenic heptaoxide) and Na2CoP1.07As0.93O7 (disodium cobalt phosphorus arsenic heptaoxide), with melilite‐like structures have been synthesized by solid‐state reactions. Their unit‐cell parameters are in agreement with Vegard's law. The obtained structural models were investigated by the bond valence sum (BVS) and charge distribution (CHARDI) validation tools and, for the latter, the structures are described as being built on anion‐centred polyhedra. The frameworks can be described as layered and formed by {[Co(P,As)2O7]2−} slabs, with alkali cations sandwiched between the layers and with the interlayer spaces increased due to P/As substitution. The BVS model was extended to a preliminary simulation of the sodium conduction properties in the studied structural type and suggests that the most probable sodium conduction pathways are bidimensional, at the (002) planes.  相似文献   

11.
Crystal Structure and Properties of Calcium and Strontium Hexathiodiphosphate(IV), Ca2P2S6 and Sr2P2S6, with a Contribution on Ca5P8 and Pb2P2S6 Ca2P2S6 and Sr2P2S6 were prepared from metal and a mixture of red phosphorus and sulfur (molar ratio M:P:S = 1:1:3) in 2 corundum crucibles inserted in quartz ampullae under vacuum (20 d 900°C). The compounds were obtained as colourless, crystalline powders containing single crystals. They crystallize in the Sn2P2S6 (high temperature form) type structure (P21/c, Z = 2): Ca2P2S6 a = 653.2(2)pm, b = 728.1(2)pm, c = 1110.1(4)pm, β = 124.00(4)°, d = 2.50(2); Sr2P2S6 a = 664.3(2)pm, b = 755.7(3)pm, c = 1139.7(3)pm, β = 124.07(2)°, d = 2.97(2). The anions P2S have staggered confirmation and are arranged with the motif of a cubic close-packing. Sr2+ is coordinated by 8S which form a twofold face-capped trigonal prism and belong to 4P2S. Structure calculations clearly show that Pb2P2S6 also crystallizes in P21/c and not in Pc [1]. Also, Raman- and IR-spectra of Ca5P8 were recorded at 20°C. The stretching vibrations of P were assigned in analogy to those of P2S in alkaline earth hexathiodiphosphates(IV). The range of their frequencies (480 to 340 cm?1) is essentially smaller and shifted to smaller values compared with P2S in Ca2P2S6 and Sr2P2S6 (620 to 390 cm?1). The symmetry of P is not D3d but C2h as in the case of P2S.  相似文献   

12.
Photochemical Reactions of Cyclopentadienylbis(ethene)rhodium with Phenanthrene, Acenaphthylene, and Triphenylene, and Unusual H Exchange between η2-Coordinated Phenanthrene or Acenaphthylene and η5-Cyclopentadienyl Ligands During UV irradiation of [CpRh(C2H4)2] (Cp = η5-C5H5) in hexane/ether in the presence of phenanthrene one ethene ligand is displaced by coordination of the 9,10 double bond of phenanthrene, and (η5-cyclopentadienyl) (η2-ethene)(η2-9,10-phenanthrene)rhodium ( 1 ) is formed. The analogous reaction in hexane in the presence of acenaphthylene occurs with formation of the complexes (η2-1,2-acenaphthylene)(η5-cyclopentadienyl)(2-ethene)rhodium 2 and bis(η2-1,2-acenaphthylene)(η5-cyclopentadienyl)rhodium 3 in which one and two ethene molecules of [CpRh(C2H4)2], respectively, are substituted by η2-1,2-acenaphthylene. The irradiation of [CpRh(C2H4)2] with triphenylene in hexane yields the compounds [CpRh(η4-1,2,3,4-triphenylene)] ( 4 ), [(CpRh)2(μ-η3: η3-triphenylene)] ( 5 ), and [(CpRh)332: η2: η2-triphenylene)] ( 6 ). Despite the partially very low yields the new complexes could be unequivocally characterized spectroscopically and in the case of 1 and 3 by X-ray structural analysis. The compounds 1 and 2 in solution reveal a novel dynamic behaviour; via an intramolecular C? H activation, exchange occurs between the protons of the η2-coordinated arene and the Cp ligand. The complex 4 in solution is fluxional, too.  相似文献   

13.
Photochemical Reactions of Cyclopentadienylbis(ethene)rhodium with Benzene Derivatives During UV irradiation of [CpRh(C2H4)2] ( 1 ) (Cp = η5‐C5H5) in hexane in the presence of hexamethylbenzene the di‐ and trinuclear arene bridged complexes [(CpRh)2(μ‐η3 : η3‐C6Me6)] ( 3 ) and [(CpRh)33‐η2 : η2 : η2‐C6Me6)] ( 4 ) are formed besides known [CpRh(η4‐C6Me6)] ( 2 ). It was shown by a separate experiment that 3 besides small amounts of 4 is formed by attack of photochemically from 1 arising CpRh fragments at the free double bond of the η4‐bonded benzene ring in 2 . Irradiation of 1 in the presence of diphenyl (C12H10) affords the compounds [(CpRh)2(μ‐η3 : η3‐C12H10)] ( 5 ) and [(CpRh)33‐η2 : η2 : η2‐C12H10)] ( 6 ) as analogues of 3 and 4 , in the presence of triptycene (C20H14) only [(CpRh)2(μ‐η3 : η3‐C20H14)] ( 7 ) is obtained; the bridging in 5 , 6 , and 7 always occurs via the same six‐membered ring of the corresponding ligand system. During the photochemical reaction of 1 in the presence of styrene (C8H8) substitution of the ethene ligands by the vinyl groups with formation of [CpRh(C2H4)(η2‐C8H8)] ( 8 ) and known [CpRh(η2‐C8H8)2] ( 9 ) is observed exclusively. The new complexes were characterized analytically and spectroscopically, in the case of 3 also by X‐ray structure analysis.  相似文献   

14.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.  相似文献   

15.
基于密度泛函理论的第一性原理对Ag_3XO_4(X=P,As,V)电子结构及光催化性质进行了对比研究。与Ag_3XO_4相比,Ag_3VO_4较好的光催化稳定性主要源于其结构中Ag-O间较强的作用力增加了对Ag+的控制,而Ag_3VO_4弱的光催化活性与其导带底中存在d轨道成份以及较低的价带边势(2.335 V,vs NHE)有关;对Ag_3AsO_4而言,其优于Ag_3XO_4光催化活性的原因基于三个方面:(1)由高分散Ags-Ags杂化轨道构成的导带底能带;(2)窄的带隙(1.91 e V);(3)宽的可见光响应范围以及高的光吸收系数。此外,Ag_3XO_4(X=P,As,V)均为间接带隙半导体光催化材料,其中,Ag_3VO_4有用于分解水制氢研究的可能;上述计算结果与实验结果吻合。  相似文献   

16.
Structures of AgAF6 (A=Sb, Ta) have been determined by X-ray single crystal studies at ambient temperatures. AgSbF6 crystallizes in space group Ia with a=979.85(4) pm, V=9.4076(12)×108 pm3, z=8, and AgTaF6 crystallizes in space group P42/mcm with a=499.49(4) pm, c=960.51(8) pm, V=2.3964(6)×108 pm3, z=2. Only the crystal system and cell parameters were obtained for the isomorphic AgNbF6; primitive tetragonal, a=497.80(10) pm, b=960.40(10) pm, V=2.3799(12)×108 pm3, z=2. The results of the Raman spectroscopy of AgAF6 support the obtained structures. The structures are discussed by comparing with that of AgPF6 and AgAsF6 which have recently been determined in a series of our study.  相似文献   

17.
1,1′-Disubstituted Titanocene Dithiolene Chelates of Type (η5-Me3EC5H4)2Ti(S2C2R2) (E = C, Si, Ge) Reaction of the titanocene dichlorides (η5-Me3EC5H4)2TiCl2 (E = C, 1a ; E = Si, 1b ; E = Ge, 1c ) with the 1,2-dithiolates (NaS)2C2H2, (NaS)2C2(CN)2 or (LiS)2C6H3Me-4 gave the new titanocene dithiolene chelates (η5-Me3EC5H4)2Ti(S2C2H2) ( 2a–c ), (η5-Me3EC5H4)2Ti[S2C2(CN)2] ( 3a–c ) and (η5-Me3EC5H4)2Ti(S2C6H3Me-4) ( 4a–c ). These have been characterized by 1H NMR, IR, and mass spectroscopy, and have been compared with the unsubstituted η5-C5H5 analogues 2d, 3d and 4d . Activation energies for the chelate ring inversion in solution of 2a–c, 3a–d and 4a–c have been estimated by temperature-dependent 1H NMR spectroscopy.  相似文献   

18.
CF3S(O)F, (CF3)2SO, CF3SF3, (CF3)2SF2, and SF4 react in different manner with XeF+MF6? (M?As, Sb). An oxidative fluorination is observed by CF3S(O)F forming the persulfonium salt CF3S(O)F2+SbF6?, whereas by (CF3)2SO a simple addition product containing xenon can be isolated in form of the sulfonium salt (CF3)2SOXeF+SbF6?. On the contrary, the Lewis-acidic character of the XeF+-cation predominates against (CF3)nSF4?n (n = 0 ? 2) leading to the corresponding fluorosulfonium salts (CF3)nSF3?n +MF6? (M?As, Sb) and XeF2.  相似文献   

19.
Transition Metal Complexes of P-rich Phosphanes and Silylphosphanes. XI. Formation, Reactions, and Structures of Chromium Carbonyl Complexes from Reactions of Li(THF)22-(tBu2P)2P] with Cr(CO)5 · THF and Cr(CO)4 · NBD Reactions of Li(THF)22-(tBu2P)2P] 1 with Cr(CO)5 · THF yield Li(THF)2Et2O[Cr(CO)42-(tBu2P)2P}η1-Cr(CO)5] 2 and the compounds [Cr(CO)42-(tBu2P)2PH}] 3 , [Cr(CO)51-(tBu2P)2PH}] 4 , (tBu2P)2PH 5 and tBu2PH · Cr(CO)5 6 . The formation of 3, 4, 5 and 6 is due to byproducts coming from the synthesis of 1. 2 reacts with CH3COOH under formation of 3 . After addition of 12-crown-4 1 with NBD · Cr(CO)4 in THF forms Li(12-crown-4)2[Cr(CO)4-{η2-(tBu2P)2P}] 7 (yellow crystals). 7 reacts with CH3COOH to 3 – which regenerates 7 with LiBu – with Cr(CO)5THF to compound 2 , with NBD · Cr(CO)4 in THF to 2 and 3 (ratio 1 : 1). With EtBr, 7 forms [Cr(CO)42-(tBu2P)2PEt}] 8 , and [Cr(CO)42-(tBu2P)2PBr}] 9 with BrCH2? CH2Br. The compounds were characterized by means of 1H, 13C, 31P, 7Li NMR spectroscopy, IR spectroscopy, elementary analysis, mass spectra, and 2, 3 and 4 additionally by means of X-ray diffraction analysis. 2 crystallizes in the space group P1 with 2 formula units in the elementary cell; a = 10.137(9), b = 15.295(12), c = 15.897(14) Å; α = 101.82(7), β = 91.65(7), γ = 98.99(7)°; 3 crystallizes in the space group P2t/n with 4 molecules in the elementary unit; a = 11.914(6), b = 15.217(10), c = 14.534(10) Å; α = 90, β = 103.56(5), γ = 90°. 4 : space group P1 with 2 molecules in the elementary unit; a = 8.844(4), b = 12.291(6), c = 14.411(7) Å, α = 66.55(2), β = 89.27(2), γ = 71.44(2)°.  相似文献   

20.
On the Knowledge of the New Ionic Ozonides P(CH3)4O3 and As(CH3)4O3 P(CH3)4O3 and As(CH3)4O3 were prepared via ion exchange in liquid ammonia and characterized by X-ray-powder, IR, MS and DTA techniques. P(CH3)4O3 and As(CH3)4O3 are isotypic and have a wurtzite-like arrangement of ions with rotationally disordered O3?. (Powder data: P63mc; P(CH3)4O3: a = 687.8(2), c = 964.6(3) pm; As(CH3)4O3: a = 708.6(1), c = 991.0(3) pm). As(CH3)4O3 shows a displacive phase transition at ?135°C. The low temperature phase is orthorhombic (a = 715.8(7), b = 1 209(1), c = 943.3(1) pm).  相似文献   

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