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Die Kristallstrukturen der Titelkomplexe, deren einer zwei verschiedene Carbonylmetall-Einheiten, deren anderer zwei verschiedene Brückenliganden besitzt, wurden bestimmt. Die Stereochemie des Cr? Ni-Komplexes entspricht der Erwartung, seine Metall—Metall-Bindung ist jedoch kürzer als der Durchschnittswert aus den entsprechenden Cr2- bzw. Ni2-Verbindungen. Bei dem Fe2-Komplex ist die Gesamt-Molekülgeometrie ebenfalls normal, doch der Metall—Metall-Abstand ist deutlich kürzer als erwartet. Die Verkürzung der Metall—Metall-Bindungen steht bei beiden Komplexen in Zusammenhang mit der Minimisierung der intramolekularen sterischen Hinderung. Stereochemistry of the Metal—Metal Bond. Structures of the Compounds (CO)4Cr[μ-PMe2]2Ni(CO)2 and (CO)3Fe[μ-PMe2, μ-I]Fe(CO)3. Each with Two Different Complex Halves The crystal structures of the title complexes, one of which has two different carbonylmetal units and the other has two different bridging ligands, were determined. The stereochemistry of the Cr? Ni complex is as expected, its metal—metal bond however is shorter than the average value of the corresponding Cr2 and Ni2 compounds. For the Fe2 complex the overall molecular geometry is also normal, but the metal—metal distance is considerably shorter than expected. The shortening of the metal—metal bonds is in both complexes correlated with the minimization of intramolecular steric strain.  相似文献   

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The reaction of Na2[Fe(CO)4] with Br2CF2 in n‐pentane generates a mixture of the compounds (CO)3Fe(μ‐CO)3–n(μ‐CF2)nFe(CO)3 ( 2 , n = 2; 3 , n = 1) in low yields with 3 as the main product. 3 is obtained free from 2 by reacting Br2CF2 with Na2[Fe2(CO)8]. The non‐isolable monomeric complex (CO)4Fe=CF2 ( 1 ) can probably considered as the precursor for 2 . 3 reacts with PPh3 with replacement of two CO ligands to form Fe2(CO)6(μ‐CF2)(PPh3)2 ( 4 ). The complexes 2 – 4 were characterized by single crystal X‐ray diffraction. While the structure of 2 is strictly similar to that of Fe2(CO)9, the structure of 3 can better be described as a resulting from superposition of the two enantiomers 3 a and 3 b with two semibridging CO groups. Quantum chemical DFT calculations for the series (CO)3Fe(μCO)3–n(μ‐CF2)nFe(CO)3 (n = 0, 1, 2, 3) as well as for the corresponding (μ‐CH2) derivatives indicate that the progressively larger σ donor and π acceptor properties for the bridging ligands, in the order CO < CF2 < CH2, favor a stronger Fe–Fe bond.  相似文献   

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Synthesis and Crystal Structure of [C(NMe2)3]2[(CO)4Fe(μ‐InCl2)2Fe(CO)4] Treatment of [C(NMe2)3]2[(CO)4FeInCl3] ( 1 ) with hot water produces the dinuclear complex [C(NMe2)3]2[(CO)4Fe(μ‐InCl2)2Fe(CO)4] ( 2 ) which could be crystallized from dichloromethane/pentane. 2 crystallizes in the monoclinic space group P21/n with a = 835.7(1), b = 1187.8(1), c = 1902.7(1) pm, β = 91.877(5)° and Z = 2. The anion contains a four‐membered Fe—In—Fe—In ring with octahedral environment at the iron atom and tetrahedral coordination at the In atom.  相似文献   

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Coordinatively Unsaturated Diiron Complexes: Synthesis and Crystal Structures of [Fe2(CO)4(μ‐H)(μ‐PtBu2)(μ‐Ph2PCH2PPh2)] and [Fe2(CO)4(μ‐CH2)(μ‐H)(μ‐PtBu2)(μ‐Ph2PCH2PPh2)] [Fe2(μ‐CO)(CO)6(μ‐H)(μ‐PtBu2)] ( 1 ) reacts spontaneously with dppm (dppm = Ph2PCH2PPh2) to give [Fe2(μ‐CO)(CO)4(μ‐H)(μ‐PtBu2)(μ‐dppm)] ( 2 c ). By thermolysis or photolysis, 2 c loses very easily one carbonyl ligand and yields the corresponding electronically and coordinatively unsaturated complex [Fe2(CO)4(μ‐H)(μ‐PtBu2)(μ‐dppm)] ( 3 ). 3 exhibits a Fe–Fe double bond which could be confirmed by the addition of methylene to the corresponding dimetallacyclopropane [Fe2(CO)4(μ‐CH2)(μ‐H)(μ‐PtBu2)(μ‐dppm)] ( 4 ). The reaction of 1 with dppe (Ph2PC2H4PPh2) affords [Fe2(μ‐CO)(CO)4(μ‐H)(μ‐PtBu2)(μ‐dppe)] ( 5 ). In contrast to the thermolysis of 2 c , yielding 3 , the heating of 5 in toluene leads rapidly to complete decomposition. The reaction of 1 with PPh3 yields [Fe2(CO)6(H)(μ‐PtBu2)(PPh3)] ( 6 a ), while with tBu2PH the compound [Fe2(μ‐CO)(CO)5(μ‐H)(μ‐PtBu2)(tBu2PH)] ( 6 b ) is formed. The thermolysis of 6 b affords [Fe2(CO)5(μ‐PtBu2)2] and the degradation products [Fe(CO)3(tBu2PH)2] and [Fe(CO)4(tBu2PH)]. The molecular structures of 3 , 4 and 6 b were determined by X‐ray crystal structure analyses.  相似文献   

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Heterobinuclear Complexes: Synthesis and X‐ray Crystal Structures of [RuRh(μ‐CO)(CO)4(μ‐PtBu2)(tBu2PH)], [RuRh(μ‐CO)(CO)3(μ‐PtBu2)(μ‐Ph2PCH2PPh2)], and [CoRh(CO)4(μ‐H)(μ‐PtBu2)(tBu2PH)] [Ru3Rh(CO)73‐H)(μ‐PtBu2)2(tBu2PH)(μ‐Cl)2] ( 2 ) yields by cluster degradation under CO pressure as main product the heterobinuclear complex [RuRh(μ‐CO)(CO)4(μ‐PtBu2)(tBu2PH)] ( 4 ). The compound crystallizes in the orthorhombic space group Pcab with a = 15.6802(15), b = 28.953(3), c = 11.8419(19) Å and V = 5376.2(11) Å3. The reaction of 4 with dppm (Ph2PCH2PPh2) in THF at room temperature affords in good yields [RuRh(μ‐CO)(CO)3(μ‐PtBu2)(μ‐dppm)] ( 7 ). 7 crystallizes in the triclinic space group P 1 with a = 9.7503(19), b = 13.399(3), c = 15.823(3) Å and V = 1854.6 Å3. Moreover single crystals of [CoRh(CO)4(μ‐H)(μ‐PtBu2)(tBu2PH)] ( 9 ) could be obtained and the single‐crystal X‐ray structure analysis revealed that 9 crystallizes in the monoclinic space group P21/a with a = 11.611(2), b = 13.333(2), c = 18.186(3) Å and V = 2693.0(8) Å3.  相似文献   

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The crystal and molecular structure of the complex containing cobalt-carbon and iron-sulfur cluster cores, (μ-p-CH3C6H4C2S) (μ-n-C3H7S)Fe2(CO)6Co2(CO)6, has been determined by X-ray diffraction method. The crystals are triclinic, space group P&1bar;, with a — 9.139(2), b=9.610(1), c-17.183(2) Å, α = 84.36(1), β-89.45(1), γ=88.15(1)°, V-1501.0 Å3; Z=2, Dc=1.74 g/cm3. R=0.072, Rw=0.081. The results of the structure determination show a cobalt-carbon cluster core formed through the reaction of (μ-p-CH3C6H4C2S)(μ-n-C3H7S)Fe2(CO)6 with Co2(CO)8. In the cobalt-carbon cluster core, the bond length of the original C≡C lengthened to 1.324 Å which is close to the typical value of carbon-carbon double bond. The groups connecting the carbons of the cluster core are in cis position and lie on the opposite side of cobalt atoms. In this complex, the conformation of —SC3H7 is e-type, while that of —SC2C6H4CH3 is a-type.  相似文献   

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The carbamoyl complex [C(NMe2)3][(CO)4Fe{C(O)NMe2}] ( 1 ) reacts with InMe3 under loss of the methyl groups to produce a variety of compounds from which only the anionic cluster complexes [C(NMe2)3]3[Fe2(CO)6(μ‐CO){μ‐InFe(CO)4(μ‐O2CNMe2)InFe(CO)4}] ([C N 3]3[ 2 ]) and [C(NMe2)3]2[{(CO)4Fe}2In(O2CNMe2)]·THF ([C N 3]2[ 3 ]·THF) could be crystallized and characterized by X‐ray analyses. The anion [ 2 ]3? has a Fe2(CO)9‐like structure and both anions contain the carbaminato ligand either in a bridging or in a chelating function.  相似文献   

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[Fe2sb‐CO)(CO)3(NO)(μ‐PtBu2)(μ‐Ph2PCH2PPh2)]: Synthesis, X‐ray Crystal Structure and Isomerization Na[Fe2(μ‐CO)(CO)6(μ‐PtBu2)] ( 1 ) reacts with [NO][BF4] at —60 °C in THF to the nitrosyl complex [Fe2(CO)6(NO)(μ‐PtBu2)] ( 2 ). The subsequent reaction of 2 with phosphanes (L) under mild conditions affords the complexes [Fe2(CO)5(NO)L(μ‐PtBu2)], L = PPh3, ( 3a ); η‐dppm (dppm = Ph2PCH2PPh2), ( 3b ). In this case the phosphane substitutes one carbonyl ligand at the iron tetracarbonyl fragment in 2 , which was confirmed by the X‐ray crystal structure analysis of 3a . In solution 3b loses one CO ligand very easily to give dppm as bridging ligand on the Fe‐Fe bond. The thus formed compound [Fe2(CO)4(NO)(μ‐PtBu2)(μ‐dppm)] ( 4 ) occurs in solution in different solvents and over a wide temperature range as a mixture of the two isomers [Fe2sb‐CO)(CO)3(NO)(μ‐PtBu2)(μ‐dppm)] ( 4a ) and [Fe2(CO)4(μ‐NO)(μ‐PtBu2)(μ‐dppm)] ( 4b ). 4a was unambiguously characterized by single‐crystal X‐ray structure analysis while 4b was confirmed both by NMR investigations in solution as well as by means of DFT calculations. Furthermore, the spontaneous reaction of [Fe2(CO)4(μ‐H)(μ‐PtBu2)(μ‐dppm)] ( 5 ) with NO at —60 °C in toluene yields a complicated mixture of products containing [Fe2(μ‐CO)(CO)4(μ‐H)(μ‐PtBu2)(μ‐dppm)] ( 6 ) as main product beside the isomers 4a and 4b occuring in very low yields.  相似文献   

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Molecular and Crystal Structures of (CO)4W(μ-S-t-C4H9)2W(CO)4, η7-C7H7W(μ-SC6H4CH3)3W(CO)3 and η7-C7H7W(μ-S-n-C4H9)3W(CO)(μ-S-n-C4H9)2W(CO)4 The molecular structures of the two binuclear complexes (CO)4W(μ-S-t-C4H9)2W(CO)4 and η7-C7H7W(μ-SC6H4CH3)3W(CO)3 and of the tungsten cluster η7-C7H7W(μ-S-n-C4H9)3W(CO)-(μ-S-n-C4H9)2W(CO)4 respectively are described. In the nonlinear trinuclear cluster the central tungsten atom is connected to the two tungsten atoms by two and three μ-S-n-C4H9 bridges respectively and additionally by one W? W bond each. The coordination sphere of the W atoms is completed by a η7-C7H7 ring and four CO groups respectively; the central tungsten carries an additional CO group.  相似文献   

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Synthesis and Properties of Heteronuclear Metal Atom Clusters Re4(CO)123-GaRe(CO)5]4 and Re2(CO)8[μ-GaRe(CO)5]2 The title compounds were prepared by the reaction of gallium halides and dirhenium decacarbonyl. Crystals of the four-membered cluster Re2(CO)8[μ-GaRe(CO)5]2 gave at 3000C with aggregation of four Re atoms to an inner Re4 tetrahedron the product Re4(CO)12(CO)[μ3-GaRe(CO)5]4and with Ga2I3 shown by mass spectroscopic measurements the molecule ion Re4(CO)16+. In tetra-hydrofuran solution the cluster Re4(CO)123-GaRe(CO)5]4 and the hydride Li[C2H5)3BH] have formed the formyl complex Li4{Re4(CO)123 -GaRe(CO)4(CHO)] 4}, which was estimated by 1H n. m. r. and i. r. spectroscopic data. Both synthesized gallium rhenium carbonyl clusters were characterized by i.r. spectroscopic measurements. The comparison of these results with those of the structurally known indium rhenium carbonyl clusters led to proposals of the molecule structure of the analogous gallium rhenium compounds.  相似文献   

13.
Reaction of the binuclear μ‐carbamoyl complex [(CO)3Fe(μ‐Me2NCO)2Fe(CO)2(HNMe2)] ( 1 ) in toluene with the chelating ligands Ph2PCH2PPh2 (dppm) and Ph2PCH2CH2PPh2 (dppe) gives different results. With dppm only the complex [(CO)3Fe(μ‐Me2NCO)2Fe(CO)2(dppm)] ( 3 ) with a dangling ligand is obtained under replacement of amine, whereas with dppe depending on the reaction conditions up to three compounds are found. A 1 : 1 mixture of the educts generates the related complex [(CO)3Fe(μ‐Me2NCO)2Fe(CO)2(dppe)] ( 4 ) together with the tetranuclear complex [{(CO)3Fe(μ‐Me2NCO)2Fe(CO)2}2(dppe)] (5 ). 4 slowly converts into [(CO)3Fe(μ‐Me2NCO)2Fe(CO)(dppe)] ( 6 ) with dppe acting as a chelating ligand. 6 is the first compound in this series in which one of the five CO groups is replaced by another donor. A 2 : 1 molar ratio of 1 and dppe quantitatively produces 5 . Addition of CO to a solution of 6 proceeds under slow reversible conversion of the complex into 4 . The compounds were characterized by the usual spectroscopic methods; 3 , 5 and 6 were also studied by X‐ray diffraction analyses.  相似文献   

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Addition of NOBF4 to fac-[PPN][Fe(CO)3(TePh)3] in THF at ambient temperature results in formation of Fe2(μ-TePh)2(NO)4l Fe2(?TePh)2(CO)6 and organic products. Methylation of fac-[PPN][Fe(CO)3- (TePh)3] by Mel or [Me3O][BF4] leads to the known dimer Fe2(μ.-TePh)2(CO)6 and organic products. Fe2(μ-TePh)2(NO)4 crystallizes in the orthorhombic space group P bca, with a = 12.701(5) Å, b = 6.7935(16) Å, c = 21.299(9) Å, V = 1837.8(11) Å3, and Z = 4. The core geometry of Fe2(μ-TePh)2(NO)4 is best described as a Fe2Te2 planar rhombus with Te-Fe-Te bond angle 112.09(4)°. A Fe-Fe bond (length 2.827(2) Å) is proposed for Fe2(μ-TePh)2(NO)4 on the basis of the 18-electron rule. The iron atom adopts a distorted tetrahedral geometry with acute bridge Fe-Te-Fe angles 67.91(3)°, and bridging Fe-Te bond of length 2.53(1) Å.  相似文献   

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Halogeno-Bridged Heteronuclear Metal Atom Clusters of the Three Types Re2(CO)4L2(μ-X)2(μ-Y) (L = (C6H5)3P; X = Br, I; Y = GaRe(CO)4ax-L), Re2(CO)6L2(μ-X) (μ-GaX2) (X = I), and Re3(CO)9L3 (μ-X)33-Y) (X = Cl) The title compounds of the both types Re2(CO)4L(μ-X)2(μ-Y) [L = (C6H5)3P; X = Br, I; Y = GaRe(CO)4ax-L] and Re3(CO)9L3(μ-X)33-Y) (X = Cl) were prepared by the reaction of GaX3 (X = Cl, Br, I) and Re2(CO)8(ax-L)2 in boiling mesitylene solution. The obtained substance Re2(CO)4L2(μ-I)2(μ-Y) and carbon monoxide gave the compound of the third type Re2(CO)6L2(μ-I)(μ- GaI2). The last-named single iodo-bridged dirhenium cluster could be therefore a precursor complex of the double iodo-bridged compound. The four diamagnetic substances were characterized by 31P n.m.r. spectroscopy and their molecular structures were acertained by X-ray measurements. The result of the single crystal X-ray analysis of Re2(CO)4L2(μ-Br)2 [μ-GaRe(CO)4ax-L], a bridged coordination octahedron pair with a common face, and that of the edge-bridged pair Re2(CO)6L2(μ-I)(μ-GaI2) each possessing a Re? Re bond are especially treated in the present work.  相似文献   

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Coordinatively Unsaturated Diruthenium Complexes: Synthesis and X‐ray Crystal Structures of [Ru2(CO)n(μ‐H)(μ‐PtBu2)(μ‐Ph2PCH2PPh2)] (n = 4; 5) and [Ru2(CO)4(μ‐CH2)(μ‐H)(μ‐PtBu2)(μ‐Ph2PCH2PPh2)] The reaction of [Ru2(μ‐CO)(CO)5(μ‐H)(μ‐PtBu2)(tBu2PH)] ( 2 ) with dppm yields the dinuclear species [Ru2(μ‐CO)(CO)4(μ‐H)(μ‐PtBu2)(μ‐dppm)] ( 3 ) (dppm = Ph2PCH2PPh2). Under thermal or photolytic conditions 3 loses very easily one carbonyl ligand and affords the corresponding electronically and coordinatively unsaturated complex [Ru2(CO)4(μ‐H)(μ‐PtBu2)(μ‐dppm)] ( 4 ). 4 is also obtainable by an one‐pot synthesis from [Ru3(CO)12], an excess of tBu2PH and stoichiometric amounts of dppm via the formation of [Ru2(CO)4(μ‐H)(μ‐PtBu2)(tBu2PH)2] ( 1 ). 4 exhibits a Ru–Ru double bond which could be confirmed by addition of methylene to the dimetallacyclopropane [Ru2(CO)4(μ‐CH2)(μ‐H)(μ‐PtBu2)(μ‐dppm)] ( 5 ). The molecular structures of 3 , 4 and 5 were determined by X‐ray crystal structure analyses.  相似文献   

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Coordinatively Unsaturated Diruthenium Complexes: Synthesis and X‐Ray Crystal Structures of [Ru2(CO)4(μ‐H)(μ‐S)(μ‐PtBu2)(μ‐Ph2PCH2PPh2)], [Ru2(CO)4(μ‐X)(μ‐PtBu2)(μ‐Ph2PCH2PPh2)] (X = Cl, S2CH) [Ru2(CO)4(μ‐H)(μ‐PtBu2)(μ‐dppm)] ( 1 ) reacts in benzene with elemental sulfur to the addition product [Ru2(CO)4(μ‐H)(μ‐S)(μ‐PtBu2)(μ‐dppm)] ( 2 ) (dppm = Ph2PCH2PPh2). 2 is also obtained by reaction of 1 with ethylene sulfide. The reaction of 1 with carbon disulfide yields with insertion of the CS2 into the Ru2(μ‐H) bridge the dithioformato complex [Ru2(CO)4(μ‐S2CH)(μ‐PtBu2)(μ‐dppm)] ( 3 ). Furthermore, 1 reacts with [NO][BF4] to the complex salt [Ru2(CO)4(μ‐NO)(μ‐H)(μ‐PtBu2)(μ‐dppm)][BF4] ( 4 ), and reaction of 1 with CCl4 or CHCl3 affords spontaneously [Ru2(CO)4(μ‐Cl)(μ‐PtBu2)(μ‐dppm)] ( 5 ) in nearly quantitative yield. The molecular structures of 2 , 3 and 5 were confirmed by crystal structure analyses.  相似文献   

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