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1.
Reaction of [Rh(CO)2I]2 (1) with MeI in nitrile solvents gives the neutral acetyl complexes, [Rh(CO)(NCR)(COMe)I2]2 (R=Me, 3a; tBu, 3b; vinyl, 3c; allyl, 3d). Dimeric, iodide-bridged structures have been confirmed by X-ray crystallography for 3a and 3b. The complexes are centrosymmetric with approximate octahedral geometry about each Rh centre. The iodide bridges are asymmetric, with Rh-(μ-I) trans to acetyl longer than Rh-(μ-I) trans to terminal iodide. In coordinating solvents, 3a forms mononuclear complexes, [Rh(CO)(sol)2(COMe)I2] (sol=MeCN, MeOH). Complex 3a reacts with pyridine to give [Rh(CO)(py)(COMe)I2]2 and [Rh(CO)(py)2(COMe)I2] and with chelating diphosphines to give [Rh(Ph2P(CH2)nPPh2)(COMe)I2] (n=2, 3, 4). Addition of MeI to [Ir(CO)2(NCMe)I] is two orders of magnitude slower than to [Ir(CO)2I2]. A mechanism for the reaction of 1 with MeI in MeCN is proposed, involving initial bridge cleavage by solvent to give [Rh(CO)2(NCMe)I] and participation of the anion [Rh(CO)2I2] as a reactive intermediate. The possible role of neutral Rh(III) species in the mechanism of Rh-catalysed methanol carbonylation is discussed.  相似文献   

2.
The iron hydrido complex HFe(CO)2{P(OPh)3}{(PhO)2POC6H4} (1), was rapidly deprotonated by DBU or [BzMe3N][OH] in THF to afford the new carbonyl iron anion [Fe(CO)2{P(OPh)3}{(PhO)2POC6H4}] ([2]), containing an ortho-metallated triphenyl phosphite ligand. Complex [2] reacted with triorganostannyl and plumbyl salts and with halogens to give the octahedral FeII compounds Fe(CO)2{P(OPh)3}{(PhO)2POC6H4}(X) (X=SnPh3, 3; SnMe3, 4; PbPh3, 5; PbMe3, 6; Cl, 7; Br, 8; I, 9). The Group 14 complexes 3-6 were obtained in one isomeric form in which the PIII-donor atoms are mutually cis, the carbonyl ligands are cis and the P(OPh)3 and MR3 (M=Sn, Pb; R=Ph, Me) groups are trans as determined by solution-state IR, 31P and 13C NMR spectroscopic data. This geometry was confirmed for 3 by a single crystal X-ray diffraction study. The halide complexes, however, were obtained as a mixture of isomers. The major isomer (7, X=Cl; 8a, X=Br; 9a, X=I) has cis P atoms, trans CO groups and the halide located trans to the phosphorus atom of the ortho-metallated phosphite ligand. The structure of 9a was confirmed by an X-ray diffraction study. Two other isomers, designated 8b (X=Br) and 9b (X=I), with cis P atoms and cis CO groups were isolated from the reactions of [2] with Br2 and I2, respectively. The structure of the latter was established by X-ray crystallography and is related to 9a by exchange of the P(OPh)3 ligand and a carbonyl group such that the metal-bound C atom of the five-membered metallacycle is trans to CO. The stereo-geometry of 8b could not be unambiguously assigned from the spectroscopic data; however, two of the seven possible geometric isomers were suggested as plausible structures.  相似文献   

3.
When the iron sulfide complexes (μ-Sx)[CpFe(CO)2]2 (x = 2, 3) are treated with O-alkyl oxalyl chlorides ROCOCOCl the complexes CpFe(CO)2SCOCO2R (1) [R = Me (a), Et (b)] are obtained. Similarly, the complexes CpFe(CO)2SeCOCO2R (2) are obtained from the analogous iron selenide (μ-Se)[CpFe(CO)2]2 reaction with the same reagents. Treatment of the iron selenide with half equivalent of oxalyl chloride produces the dimeric complex [CpFe(CO)2SeCO]2 (3). The new complexes, 1, 2 and 3, have been characterized by elemental analyses, IR and 1H NMR spectroscopy. The solid state structures of 1a, 2a, 3 and [CpFe(CO)2SCO]2 (4) were determined by an X-ray crystal structure analysis.  相似文献   

4.
The mono-substituted amine derivatives [Ir4(CO)11L] (L = pyridine (1), 4-methylpyridine (2), 4-ter-butyl pyridine (3), 3,5-dimethylpyridine (4), 3,4-dimethylpyridine (5)) were obtained by the reaction of [Ir4(CO)11Br] with the corresponding aromatic amine. In the solid state, cluster 2 has an approximate Cs symmetry with all terminal ligands as shown by an X-ray analysis. In solution, this unbridged structure is in dynamic equilibrium with two other isomeric forms having three edge-bridging CO’s on a common basal face and the amine ligand coordinated in axial or in radial position relative to this face.  相似文献   

5.
The organotin complex [Ph3SnS(CH2)3SSnPh3] (1) was synthesized by PdCl2 catalyzed reaction between Ph3SnCl and disodium-1,3-propanedithiolate which in turn was prepared from 1,2-propanedithiol and sodium in refluxing THF. Reaction of 1 with Ru3(CO)12 in refluxing THF affords the mononuclear complex trans-[Ru(CO)4(SnPh3)2] (2) and the dinuclear complex [Ru2(CO)6(μ-κ2-SCH2CH2CH2S)] (3) in 20 and 11% yields, respectively, formed by cleavage of Sn-S bond of the ligand and Ru-Ru bonds of the cluster. Treatment of pymSSnPPh3 (pymS = pyrimidine-2-thiolate) with Ru3(CO)12 at 55-60 °C also gives 2 in 38% yield. Both 1 and 2 have been characterized by a combination of spectroscopic data and single crystal X-ray diffraction analysis.  相似文献   

6.
The crystal structures of the four-coordinate trans-[Rh(Cl)(CO)(SbPh3)2] (1) and the five-coordinate trans-[Rh(Cl)(CO)(SbPh3)3] (2) are reported, as well as the unexpected oxidative addition product, trans-[Rh(I)2(CH3)(CO)(SbPh3)2] (3), obtained from the reaction of 2 with CH3I. The formation constants of the five-coordinate complex were determined in dichloromethane, benzene, diethyl ether, acetone and ethyl acetate as 163±8, 363±10, 744±34, 1043±95 and 1261±96 M−1, respectively. While coordinating solvents facilitate the formation of the five-coordinate complex, the four-coordinate complex could be obtained from diethyl ether due to the favorable low crystallization energy. The tendency of stibine ligands to form five-coordinate rhodium(I) complexes is attributed mainly to electron deficient metal centers in these systems, with smaller contributions by the steric effects. The average effective cone angle for the SbPh3 ligand in the three crystallographic studies was determined as 139° with individual values ranging from 133 to 145°.  相似文献   

7.
Addition of excess CF3CO2H (HTFA) to [Rh2Pt2(CO)7(PPh3)3], I, under nitrogen results in the formation of a salt (X2+ Y2−), which contains only the second example of a di-cationic carbonyl hydride tetra-nuclear cluster, [H2Rh2Pt2(CO)7(PPh3)3]2+, X2+, and a presently partially characterized polymetallic anion Y2−. The di-cation X2+ has been characterized by mass spectrometry and a variety of multinuclear NMR methods. Since there is no difference in the electron count for I and X2+, it is probable that both I and X2+ adopt similar butterfly metallic frameworks with a Rh-Rh hinge; in X2+, there are two bridging hydrides to the same wing-tip Pt but the phosphine site occupancies on the Rh2Pt2-framework in I and X2+ are different.  相似文献   

8.
Substitution of thf ligands in [Cr(thf)3Cl3] and [Cr(thf)2(OH2)Cl3] was investigated. 2,2′-Bipyridine (bipy) was reacted with [Cr(thf)3Cl3] to form [Cr(bipy)(thf)Cl3] (1), which was subsequently reacted with water to give [Cr(bipy)(OH2)Cl3] (2). Reaction of 1 with acetonitrile (CH3CN), pyridine (py) and pyridine derivatives to form [Cr(bipy)(L)Cl3] (L = CH3CN 3, py 4 and 4-pyR with R = NH25, But6 and Ph 7). In addition, the substitution of bipy in [Cr(thf)3Cl3] was followed by 1H NMR spectroscopy at room temperature, which showed completion of the reaction in ca. 100 min. Complex 2 was characterised by single crystal X-ray diffraction. The theoretical powder diffraction pattern of 2 was compared to the experimentally obtained powder X-ray diffraction pattern, and shows excellent agreement. The dimer [Cr2(bipy)2Cl4(μ-Cl)2] was cleaved asymmetrically to give the anionic complex [Cr(bipy)Cl4] (8) and [Cr(bipy)2Cl2]+ (9). Complexes 8 and 9 were characterised by single crystal X-ray diffraction.  相似文献   

9.
[PPN][Se5Fe(NO)2] (1) and [K-18-crown-6-ether][S5Fe(NO)2] (2′) were synthesized and characterized by IR, UV-Vis, EPR spectroscopy, magnetic susceptibility, and X-ray structure. [PPN][Se5Fe(NO)2] easily undergoes ligand exchange with S8 and (RS)2 (R = C7H4SN (5), o-C6H4NHCOCH3 (6), C4H3S (7)) to form [PPN][S5Fe(NO)2] and [PPN][(SR)2Fe(NO)2]. The reaction displays that [E5Fe(NO)2] (E = Se (3), S (4)) facilely converts to [Fe4E3(NO)7] by adding acid HBF4 or oxidant [Cp2Fe][BF4] in THF, respectively. Obviously, complexes 1 and 2′ serve as the precursors of the Roussin’s black salts 3 and 4. The electronic structure of {Fe(NO)2}9 core of [Se5Fe(NO)2] is best described as a dynamic resonance hybrid of {Fe+1(NO)2}9 and {Fe−1(NO+)2}9 modulated by the coordinated ligands. The findings, EPR signal of g = 2.064 for 1 at 298 K, implicate that the low-molecular-weight DNICs and protein-bound DNICs may not exist with selenocysteine residues of proteins as ligands, since the existence of protein-bound DNICs and low-molecular-weight DNICs in vitro has been characterized with a characteristic EPR signal at g = 2.03. In addition, complex 2′ treated human erythroleukemia K562 cancer cells exposed to UV-A light greatly decreased the percentage survival of the cell cultures.  相似文献   

10.
The synthesis of [K]2[CpFe(CN)3] (1) and its pentamethylcyclopentadienyl analog (2) has been described via the photolysis of the corresponding [K][CpFe(CO)(CN)2] salts in methanol in the presence of KCN. The structure of complex 1 has been characterized by means of X-ray crystallography, where the potassium ions are interacting with the N atoms of the cyanide ligands. As expected, the average νCN stretching frequency in the anion is 16 cm−1 higher than that in the more electron-donating pentamethylcyclopentadienyl derivative.  相似文献   

11.
Novel bipyridine-type linking ligands L1 ((4-py)-CHN-C10H6-NCH-(4-py)) and L2 ((3-py)-CHN-C10H6-NCH-(3-py)), a pair of isomers due to possessing different pairs of terminal pyridyl groups, were prepared by the Schiff-base condensation. In ligand L1, the N?N separation between the terminal pyridyl groups is 16.0 Å, with their nitrogen donor atoms at the para positions (4,4′). The corresponding N?N separation in ligand L2 is 14.2 Å, with the nitrogen donor atoms at the meta positions (3,3′). 1-D zigzag-chain coordination polymers [Zn(L1)(NO3)2] (1) and [Zn(L2)(NO3)2] (2) were prepared by reactions of Zn(NO3)2 · 6H2O with ligands L1 and L2, respectively, by solution diffusion. Polymer 3, [Cd(L1)1.5(NO3)2], prepared from Cd(NO3)2 · 4H2O and L1, exhibits a 1-D ladder structure, whose repeating ladder unit consists of four Cd metals and four L1 ligands to create a large 76-membered ring with dimensions of 20.8 × 20.8 Å. All products were structurally characterized by X-ray diffraction.  相似文献   

12.
The preparation, crystal structures and magnetic properties of three copper(II) compounds of formulae [Cu2(dmphen)2(dca)4] (1), [Cu(dmphen)(dca)(NO3)]n (2) and [Cu(4,4-dmbpy)(H2O)(dca)2] (3) (dmphen=2,9-dimethyl-1,10-phenanthroline, dca=dicyanamide and 4,4-dmbpy=4,4-dimethyl-2,2-bipyridine) are reported. The structure of 1 consists of discrete copper(II) dinuclear units with double end-to-end dca bridges whereas that of 2 is made up of neutral uniform copper(II) chains with a single symmetrical end-to-end dca bridge. Each copper atom in 1 and 2 is in a distorted square pyramidal environment: two (1) or one (2) nitrile-nitrogen atoms from bridging dca groups, one of the nitrogen atoms of the dmphen molecule (1 and 2) and either one nitrile-nitrogen from a terminal dca ligand (1) or a nitrate-oxygen atom (2) build the equatorial plane whereas the second nitrogen atom of the heterocyclic dmphen fills the axial position (1 and 2). The copper-copper separations through double (1) and single (2) end-to-end dca bridges are 7.1337(7) (1) and 7.6617(7) (2). Compound 3 is a mononuclear copper(II) complex whose structure contains two neutral and crystallographically independent [Cu(4,4-dmbpy)(H2O)(dca)2] molecules which are packed in two different layer arrangements running parallel to the bc-plane and alternating along the a-axis. The copper atoms in both molecules have slightly distorted square pyramidal surroundings with the two nitrogen atoms of the 4,4-dmbpy ligand and two dca nitrile-nitrogen atoms in the basal plane and a water oxygen in the apical position. A semi co-ordinated dca nitrile-nitrogen from a neighbour unit [2.952(6) Å for Cu(2)-N] is in trans position to the apical water molecule in one of the two molecules, this feature representing part of the difference in supramolecular connections in the alternating layers referred to above. Magnetic susceptibility measurements for 1-3 in the temperature range 1.9-290 K reveal the occurrence of weak antiferromagnetic interactions through double [J=−3.3 cm−1 (1), ] and single [J=−0.57 cm−1 (2), ] dca bridges and across intermolecular contacts [θ=−0.07 K (3)].  相似文献   

13.
Two new heterometallic complexes, [Cu(en)(H2O)]2[Fe(CN)6]·4H2O (1) and [Cu(en)2][KFe(CN)6] (2), have been isolated from the reactions of CuCl2 and en with K3[Fe(CN)6] in different molar ratios. Both complexes have been characterized by X-ray analyses, IR spectra and elemental analyses. Complex 1 is a cyanide bridged bimetallic assembly, its crystal structure consists of a two-dimensional polymeric sheet with two different rings, one a four-membered square ring and another a 12-membered hexagonal ring. The Fe(II) ion of 1 has two terminal, two linear bridging and two 1,1 en-on bridging cyanide groups. In the crystal structure of 2, the neighboring [Fe(CN)6]3− units are bridged by the K+ and the [K[Fe(CN)6]]2− units forming a three-dimensional network structure. The [Cu(en)2]2+ units fill in the holes of the network acting as counter cations and charge compensations. Variable temperature magnetic susceptibility studies of 1 indicate that the complex exhibits ferromagnetic interaction between the Cu(II) ions.  相似文献   

14.
Cyclometalation of benzo[h]quinoline (bzqH) by [RuCl(μ-Cl)(η6-C6H6)]2 in acetonitrile occurs in a similar way to that of 2-phenylpyridine (phpyH) to afford [Ru(bzq)(MeCN)4]PF6 (3) in 52% yield. The properties of 3 containing ‘non-flexible’ benzo[h]quinoline were compared with the corresponding [Ru(phpy)(MeCN)4]PF6 (1) complex with ‘flexible’ 2-phenylpyridine. The [Ru(phpy)(MeCN)4]PF6 complex is known to react in MeCN solvent with ‘non-flexible’ diimine 1,10-phenanthroline to form [Ru(phpy)(phen)(MeCN)2]PF6, being unreactive toward ‘flexible’ 2,2′-bipyridine under the same conditions. In contrast, complex 3 reacts both with phen and bpy in MeCN to form [Ru(bzq)(LL)(MeCN)2]PF6 {LL = bpy (4) and phen (5)}. Similar reaction of 3 in methanol results in the substitution of all four MeCN ligands to form [Ru(bzq)(LL)2]PF6 {LL = bpy (6) and phen (7)}. Photosolvolysis of 4 and 5 in MeOH occurs similarly to afford [Ru(bzq)(LL)(MeCN)(MeOH)]PF6 as a major product. This contrasts with the behavior of [Ru(phpy)(LL)(MeCN)2]PF6, which lose one and two MeCN ligands for LL = bpy and phen, respectively. The results reported demonstrate a profound sensitivity of properties of octahedral compounds to the flexibility of cyclometalated ligand. Analogous to the 2-phenylpyridine counterparts, compounds 4-7 are involved in the electron exchange with reduced active site of glucose oxidase from Aspergillus niger. Structure of complexes 4 and 6 was confirmed by X-ray crystallography.  相似文献   

15.
The crystal structures of [Cr(NO)(NH3)5](PF6)2 (red) and [Cr(NO)(NH3)5]Cl(PF6) (brown) have been determined. The [Cr(NO)(NH3)5]2+(A) complex cations in these compounds have a slightly distorted octahedral geometry with a strictly linear Cr-N-O arrangement (from symmetry). The short interatomic distances (2.399 Å × 4) between the O (nitrosyl) and H (ammonia in adjacent complex cations) atoms in A(PF6)2 indicate the existence of hydrogen bonds, while the interatomic distances (3.258 Å × 8) between those in ACl(PF6) are much longer, and the hydrogen bonds should be weak in spite of the presence of the smaller counter anion of chloride ion in ACl(PF6). Comparisons of the five crystal structures of A(PF6)2, ACl2, ACl(ClO4), ACl(PF6), and A(ClO4)2 have led to the conclusion that the existence of the strong hydrogen bonds gives red crystals of A(PF6)2, while the absence of hydrogen bonds results in the formation of green crystals of A(ClO4)2 (O ? H, 3.595 Å × 2). The color change of the crystals (from red to green) with the change of outer sphere anions is attributed to the change of the strength of the hydrogen bonding between the complex cations.  相似文献   

16.
Two rhenium(I) tricarbonyl complexes with the tridentate monoanionic NSO ligands, 4-(benzimidazol-2-yl)-3-thiabutanoic acid (complex 3) and [1-(11-carboxyundecanyl)-4-(benzimidazol-2-yl)]-3-thiabutanoic acid (complex 4) were synthesized and characterized by spectroscopic methods and elemental analysis. X-ray crystallographic analysis of complex 3 revealed a distorted octahedral geometry around rhenium defined by the three facially bound CO groups and the NSO donor atom set of the tridentate ligand. The analogous technetium-99m complexes (complexes 5 and 6) were also prepared quantitatively by reaction of the NSO ligands with the fac-[99mTc(H2O)3(CO)3]+ synthon and their identity was established by chromatographic comparison to their rhenium congeners. Biodistribution in mice of complex 6 bearing the fatty acid chain showed significant heart uptake (6.26 ± 0.79% ID/g p.i.) at 1 min accompanied, however, with a heart:blood ratio below 1.  相似文献   

17.
A hexarhenium cyanohydroxo anionic cluster complex [Re6Se8(CN)4(OH)2]4− was synthesized for the first time starting from [Re6Se8(OH)6]4−, which was crystallized as a salt of the composition Cs2.75K1.25[Re6Se8(CN)4(OH)2]·H2O (1). The reaction of the complex with Cu2+ in an aqueous ammonia or methylamine solutions afforded [Cu(NH3)5]2[Re6Se8(CN)4(OH)2]·8H2O (2) or [{Cu(CH3NH2)4}2Re6Se8(CN)4(OH)2] (3), respectively. All of these three compounds were characterized by a single-crystal X-ray diffraction method. Compound 1 is crystallized in the tetragonal space group I4/m with eight formula units per cell (a = b = 17.4823(14) Å, c = 19.430(2) Å, V = 5938.3(10) Å3); compound 2 is crystallized in the monoclinic space group P21/n with two formula units per cell (a = 12.1845(13) Å, b = 8.6554(9) Å, c = 19.2568(19) Å, β = 91.081(2)°, V = 2030.5(4) Å3); compound 3 is crystallized in the orthorhombic space group Cmcm with four formula units per cell (a = 19.816(4) Å, b = 14.611(3) Å, c = 13.751(3) Å, V = 3981.2(13) Å3). The luminescence properties of 1 were studied in both aqueous solution and solid state. In addition, the electronic structure of [Re6Se8(CN)4(OH)2]4− was elucidated by DFT calculations.  相似文献   

18.
《Inorganica chimica acta》2005,358(3):520-526
The strong affinity of coordinated biimidazole for chloride ion via N-H?Cl hydrogen bonding has been used as a strategy to build up two different modular assemblies between chloride and biimidazole-metal modules. The crystal structure of these two new metal-containing architectures, {[Cu(H2biim)2]Cl2 (1) and [Zn(Cl)(H2biim)2]Cl (2)}, is reported. The EPR spectrum of 1 is also discussed.  相似文献   

19.
The crystalline compounds (Hbipy)2[Ge(C2O4)3] (1) and (Hphen)2[Ge(C2O4)3] · 2(H2O) (2) [Hbipy+ is the 2,2′-bipyridinium cation (C10H9N2), and Hphen+ is the 1,10′-phenathrolinium cation (C12H9N2)] were isolated from mild hydrothermal syntheses and their structures were elucidated from single-crystal X-ray diffraction. The two compounds were further characterised by vibrational spectroscopy (FT-IR and FT-Raman), thermogravimetric analysis (TGA) and CHN elemental composition. Compounds 1 and 2 comprise the tris(oxalato-O,O′)germanate dianion complex, [Ge(C2O4)3]2−, which co-crystallises with Hbipy+ (in 1), or Hphen+ and water molecules (in 2). In 1, the germanium oxalate anionic complex, [Ge(C2O4)3]2−, and the Hbipy+ organic residues interact mutually via N-H?O hydrogen bonding interactions, leading to supramolecular discrete hydrogen-bonded units which are further interconnected via π-π stacking. Compound 2, on the other hand, exhibits a more complex hydrogen bonding network due to the presence of the water molecules of crystallisation which, along with π-π stacking between neighbouring Hphen+ residues, mediate the crystal packing.  相似文献   

20.
The reaction of 2-(2-aminophenyl)benzothiazole (Habt) with [Re(CO)5Br] led to the isolation of the rhenium(I) complex fac-[Re(Habt)(CO)3Br] (1). With trans-[ReOCl3(PPh3)2], the ligand Habt decomposed to form the oxofree rhenium(V) complex [Re(itp)2Cl(PPh3)] (2) (itp = 2-amidophenylthiolate). From the reaction of trans-[ReOBr3(PPh3)2] with 2-(2-hydroxyphenyl)benzothiazole (Hhpd) the complex [ReVOBr2(hpd)(PPh3)] (3) was obtained. Complexes 1-3 are stable and lipophilic. 1H NMR and infrared assignments, as well as the X-ray crystal structures, of the complexes are reported.  相似文献   

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