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1.
In order to study the effects of R group on Fe-Hg interactions and 31P chemical shifts, the structures of mononuclear complexes Fe(CO)3(PPh2R)2 (R=pym: 1, fur: 2, py: 3, thi: 4; pym=pyrimidine, fur=furyl, py=pyridine, thi=thiazole) and binuclear complexes [Fe(CO)3(PPh2R)2(HgCl2)] (R=pym: 5, fur: 6, py: 7, thi: 8) were studied by using the density functional theory (DFT) PBE0 method. The 31P chemical shifts were calculated by PBE0-GIAO method. Nature bond orbital (NBO) analyseswere also performed to explain the nature of the Fe-Hg interactions. The conclusions can be drawn as follows: (1) The complexes with nitrogen donor atoms are more stable than those with O or S atoms. The more N atom there are, the higher is the stabilitity of the complex. (2) The Fe-Hg interactions play a dominant role in the stabilities of the complexes. In 5 or 6, there is a σ-bond between Fe and Hg atoms, However, in 7 and 8, the Fe-Hg interations act as σP-Fe→nHg and σC-Fe→nHg delocalization. (3) Through Fe邛Hg interactions, there is charge transfer from R groups towards the P, Fe, and Hg atoms, which increases the electron density on P nucleus in binuclear complexes. As a result, compared with their mononuclear complexes, the 31P chemical shifts in binuclear complexes show some reduction. 相似文献
2.
In order to study the Fe-Cu interactions and their effects on 31p NMR, the structures of mononuclear complex Fe(CO)3fPhzPpy)a 1 and binuclear complexes Fe(CO)3(PhEPpy)z(CuXn) (2: Xn = Cl2^2-, 3: Xn = Cl-, 4: Xn = Br-) are calculated by density functional theory (DFT) PBE0 method. For complexes 1, 3 and 4, the 31p NMR chemical shifts calculated by PBE0-GIAO method are in good agreement with experimental results. The 31p chemical shift is 82.10 ppm in the designed complex 2. The Fe-Cu interactions (including Fe→Cu and Fe←Cu charge transfer) mainly exhibit the indirect interactions. Moreover, the Fe-Cu(I) interactions (mostly acting as σFe-p→4Scu and aFe-C→4Scu charge transfer) in complexes 3 and 4 are stronger than Fe-Cu(Ⅱ) interactions (mostly acting as σFe-p→4Scu and σFe-p←4Sc,) in complex 2. In complex 2, the stronger Fe←Cu interac- tions, acting as σFe-p←44SCu charge transfer, increase the electron density on P nucleus, which causes the upfield 31p chemical shift compared with mononuclear complex 1. For 3 and 4, although a little deshielding for P nucleus is derived from the delocalization of σFe-p→4Scu due to the Fe→Cu interactions, the stronger σFe-c→np charge-transfer finally increases the electron density on P nucleus. As a result, an upfield 31p chemical shift is observed compared with 1. The stability follows the order of 2〉3=4, indicating that Fe(CO)3(PhzPpy)2(CuCl2) is stable and could be synthesized experimentally. The N-Cu(Ⅱ) interaction plays an important role in the stability of 2. Because the delocalization of σFe-p→4SCu and σFe-c→πc-o weakens the a bonds of Fe-C and ~r bonds of CO, it is favorable for increasing the catalytic activity of binuclear complexes. Complexes 3 and 4 are expected to show higher catalytic activity compared to 2. 相似文献
3.
对PPh2py配合物[M(CO)3(PPh2py)2](M=Fe, Ru)的三种构型的异构体1-6进行了研究. 其中PPh2py以两个P原子与M配位形成HH构型1(Fe)和4(Ru), 以一个P和一个N原子与M配位形成HT构型2(Fe)和5(Ru), 以两个N原子与M配位形成HH’构型3(Fe)和6(Ru). 结果表明, (1) PPh2py中P原子对HOMO轨道的贡献最大, PPh2py作为电子给体时易以P原子与金属原子结合. (2)从分子能量和相互作用能数据表明, 配合物中HH构型最稳定, HH'构型最不稳定, 这与合成产物为HH构型的结果一致. (3) 键长和Wiberg键级均表明P—M键比N—M键结合力强. P、M原子间存在σ键, 而N、Fe原子间仅存在nN→n*M或nN→σ*M-P的电荷转移作用. (4) HH构型中M对HOMO的贡献最大, PPh2py向M的电荷转移最强, 使M的负电荷最大, 故HH构型最易作为电子给体以M原子与第二个金属配位形成双核配合物. 相似文献
4.
应用密度泛函理论(DFT)的PBE0方法, 金属原子采用SDD基组, H、C、O和N原子采用6-31G*基组, P和Cl原子采用6-311G*基组, 对单核配合物Ir(CO)Cl(Ph2Ppy)2(1), 双核配合物Ir(CO)(Cl)2(Ph2Ppy)2HgCl(2)、Ir(CO)Cl(Ph2Ppy)2HgCl2(3)和Ir(CO)(Cl)2(HgCl2)(Ph2Ppy)2HgCl(4)进行结构优化, 并在优化的基础上采用基组重叠误差(BSSE)校正计算相互作用能, 通过自然键轨道(NBO)和前线轨道分析研究Ir-Hg相互作用和氧化还原反应的实质. 通过计算发现, Ir(CO)Cl(Ph2Ppy)2与HgCl2发生氧化还原反应得到的产物2和4比非氧化还原产物3稳定. Ir-Hg相互作用强度顺序为3<4<2, 且随着Ir-Hg相互作用强度增大, HOMO轨道中Ir和Hg成分逐渐趋于接近. 配合物2和4都具有一对Ir-Hg成键与反键轨道, 其成键轨道的组成分别为0.5985sd0.06Hg+0.8012sd2.48Ir和0.5794sd0.05Hg+0.8151sd2.48Ir, 但3中Ir与Hg的相互作用较弱, 只存在弱相互作用(电荷转移作用), 表现为nIr→nHg的直接作用和σIr—P(1)→nHg、σIr—C(1)→nHg的间接作用. 相似文献
5.
Theoretical Studies on the Fe-M Interactions and 31P NMR in Fe(CO)3(EtPhPpy)2MX2 (X=NCS,SCN, Cl; M=Zn,Cd, Hg)
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To study the Fe?M interactions and their effects on 31P NMR, the structures of Fe(CO)3(EtPhPpy)2 1,Fe(CO)3(EtPhPpy)2M(NCS)2 (2: M=Zn, 3: M=Cd, 4: M=Hg) and Fe(CO)3(EtPhPpy)2CdX2 (5: X=Cl,6: X=SCN) were investigated by density functional theory (DFT) PBE0 method. The stabilities S of complexes follow S(2)>S(3)>S(4) and S(3)≈S(6)>S(5), indicating that 6 is stable and may be synthesized.The complexes with thiocyanate are more stable than that with chloride in Fe(CO)3(EtPhPpy)2CdX2.The strength I of Fe-M interactions follows I(2)≈I(3)相似文献
6.
配合物[M(CO)3(PPh2py)2](M=Fe,Ru)异构体的理论研究 总被引:4,自引:0,他引:4
对PPh2py配合物[M(CO)3(PPh2py)2](M=Fe,Ru)的三种构型的异构体1-6进行了研究.其中PPh2py以两个P原子与M配位形成HH构型1(Fe)和4(Ru),以一个P和一个N原子与M配位形成HT构型2(Fe)和5(Ru),以两个N原子与M配位形成HH'构型3(Fe)和6(Ru).结果表明,(1)PPh2py中P原子对HOMO轨道的贡献最大,PPh2py作为电子给体时易以P原子与金属原子结合.(2)从分子能量和相互作用能数据表明,配合物中HH构型最稳定,HH'构型最不稳定,这与合成产物为HH构型的结果一致.(3)键长和Wiberg键级均表明P-M键比N-M键结合力强.P、M原子间存在σ键,而N、Fe原子间仅存在nN→nM或nN→σM-P的电荷转移作用.(4)HH构型中M对HOMO的贡献最大,PPh2py向M的电荷转移最强,使M的负电荷最大,故HH构型最易作为电子给体以M原子与第二个金属配位形成双核配合物. 相似文献
7.
Xuan Xu Liang Fang Guo-Chun Yang Zhong-Min Su 《Journal of organometallic chemistry》2006,691(9):1927-1933
To study the Ru-M interactions and their effects on 31P NMR, complexes [Ru(CO)3(Ph2Ppy)2] (py = pyridine) (1) and [Ru(CO)3(Ph2Ppy)2MCl2] (M = Zn, 2; Cd, 3; Hg, 4) were calculated by density functional theory (DFT) PBE0 method. Moreover, the PBE0-GIAO method was employed to calculate the 31P chemical shifts in complexes. The calculated 31P chemical shifts in 1-3 follow 2 > 3 > 1 which are consistent to experimental results, proving that PBE0-GIAO method adopted in this study is reasonable. This method is employed to predict the 31P chemical shift in designed complex 4. Compared with 1, the 31P chemical shifts in 2-4 vary resulting from adjacent Ru-M interactions. The Ru → M or Ru ← M charge-transfer interactions in 2-4 are revealed by second-order perturbation theory. The strength order of Ru → M interactions is the same as that of the P-Ru → M delocalization with Zn > Cd > Hg, which coincides with the order of 31P NMR chemical shifts. The interaction of Ru → M, corresponding to the delocalization from 4d orbital of Ru to s valence orbital of M2+, results in the delocalization of P-Ru → M, which decreases the electron density of P nucleus and causes the downfield 31P chemical shifts. Except 2, the back-donation effect of Ru ← M, arising from the delocalization from s valence orbital of M2+ to the valence orbital of Ru, is against the P-Ru → M delocalization and results in the upfield 31P chemical shifts in 4. Meanwhile, the binding energies indicate that complex 4 is stable and can be synthesized experimentally. However, as complex [Ru(CO)3(Ph2Ppy)2HgCl]+5 is more stable than 4, the reaction of 1 with HgCl2 only gave 5 experimentally. 相似文献
8.
Fiorella Bachechi Alfredo Burini Rossana Galassi Bianca Rosa Pietroni 《Journal of Molecular Structure》2005,740(1-3):119-123
The Hg(II) complex [Hg(TFP)2(OTFP)3][ClO4]2 with TFP=tri-2-furyl-phosphine and OTFP=tri-2-furylphosphinoxide has been prepared and characterised. It crystallises in the hexagonal P63/m space group with Z=2, a=13.308(3), c=21.092 (4) Å, V=3235(1) Å3. The structure of the complex cation consists of independent molecules with Hg pentacoordinated in exact trigonal bipyramidal geometry. 相似文献
9.
Paul Conway Seamus M. Grant A.R. Manning F.S. Stephens 《Journal of organometallic chemistry》1980,186(3):C61-C63
[Fe(CO)2 {P(OR)3}2 (SO2)] complexes (R = aryl) exist in solution as equilibrium mixtures of two isomers; both have been shown by X-ray diffraction studies (where R = Ph or o-MeC6H4) to have planar coordination about SO2 and trigonal bipyramidal coordination about Fe, but in one isomer (R = Ph) the equatorial plane is occupied by SO2 and two CO ligands whilst in the other one (R = o-MeC6H4) it is occupied by the SO2 and two P ligands. 相似文献
10.
The paper presents a combined experimental and computational study of mono- and disubstituted Re(V) oxocomplexes obtained in the reactions of [ReOX3(EPh3)2] (X = Cl, Br; E = P, As) with 2-(2-hydroxyphenyl)-1H-benzimidazole (Hhpb). From the reactions of [ReOX3(PPh3)2] with Hhpb in molar ratio 1:1 cis and trans stereoisomers of [ReOX2(hpb)(PPh3)] were isolated, whereas the [ReOX3(AsPh3)2] oxocompounds react with Hhpb to give only cis-halide isomers. The [ReOX2(hpb)(EPh3)] and [ReO(OMe)(hpb)2]·MeCN complexes have been characterized spectroscopically and structurally (by single-crystal X-ray diffraction). The DFT and TDDFT calculations have been carried out for the trans-[ReOBr2(hpb)(PPh3)], cis-[ReOBr2(hpb)(AsPh3)] and [ReO(OMe)(hpb)2], and their UV–Vis spectra have been discussed on this basis. 相似文献
11.
A new class of M(II)–Hg(II) (M=Cu(II), Co(II), Ni(II)) mixed-metal coordination polymers, Cu(2-pyrazinecarboxylate)2HgCl2 (4), [Co(2-pyrazinecarboxylate)2(HgCl2)2] · 0.61H2O (5) and [Ni(2-pyrazinecarboxylate)2(HgCl2)2] · 0.77H2O (6), have been prepared by self assembly of metal-containing building blocks, M(2-pyrazinecarboxylate)2 · (H2O)2(M=Cu(II), Co(II), Ni(II)), with HgCl2. Compounds 4–6 were characterized fully by IR, elemental analysis and single crystal X-ray diffraction. Compound 4 crystallized in the monoclinic space group C2/c, with a=17.916(5) Å, b=7.223(2) Å, c=13.335(4) Å, β=128.726(3)°, V=1346.2(6) Å3, Z=4. It contains alternating Hg(II) and Cu(II) metal centers that are cross-linked by 2-pyrazinecarboxylate spacers and chlorine co-ligands to generate a unique three-dimensional Hg(II)–Cu(II) mixed metal framework. Compound 5 crystallized in the triclinic space group P
, with a=6.3879(7) Å, b=6.6626(8) Å, c=13.2286(15) Å, α=96.339(2)°, β=91.590(2)°, γ=113.462(2)°, V=511.71(10) Å3, Z=1. Compound 6 also crystallized in the triclinic space group P
, with a=6.3543(8) Å, b=6.6194(8) Å, c=13.2801(16) Å, α=96.449(2)°, β=92.263(2)°, γ=113.541(2)°, V=506.67(11) Å3, Z=1. Compounds 5 and 6 are isostructural and in the solid state the Hg(II)M(II)Hg(II) units are connected by Hg2Cl2 linkages to produce a novel M(II)–Hg(II) (M=Co(II), Ni(II)) zigzag mixed-metal chain, in which a new type of M–M′–M′–M array was observed. The metal containing building blocks, M(2-pyrazinecarboxylate)2 · (H2O)2 (M=Cu(II), Co(II), Ni(II)), exhibit different connectivities to HgCl2 depending on the metal cation contained within them. 相似文献
12.
Methylpalladium(II) dithiolate complexes of the type [PdMe(SS)(ER3] (SS = S2 CNR2 (R = Me or Et), S2COEt, S2P(OR)2 (R = Et, nPr, iPr), S2PPh2; ER3 = PMePh2, PPh3, AsPh3) have been synthesized by the reaction of [Pd2Me2(μ-Cl)2(PMePh2)2] with sodium/potassium/ammonium salts of the dithio acid or by treatment of [PdMeCl(cod)] with ER3 followed by sodium/potassium/ammonium salts of the dithio ligand. All the complexes were characterized by elemental analysis, IR and nuclear magnetic resonance (1H, 31P) data. 相似文献
13.
The reactions of [ReX2(η2-N2COPh-N′,O)(PPh3)2] with 4-phenylpyrimidine have been performed. As a result, the two complexes [ReX2(N2COPh)(4-PhPyr)(PPh3)2] (X = Cl, Br) (4-PhPyr = 4-phenylpyrimidine), isostructural in the solid state, have been obtained. The crystal and molecular structures of ([ReCl2(N2COPh)(4-PhPyr)(PPh3)2])2·CHCl3 (1) and ([ReBr2(N2COPh)(4-PhPyr)(PPh3)2])2·CHCl3 (2) have been determined. The electronic structure of [ReCl2(N2COPh)(4-PhPyr)(PPh3)2] has been examined using the density functional theory (DFT) method. The spin-allowed electronic transitions of 1 have been calculated with the time-dependent DFT method, and the UV–Vis spectrum of [ReCl2(N2COPh)(4-PhPyr)(PPh3)2] has been discussed on this basis. 相似文献
14.
The syntheses and 13C, 17O, 29Si and 31P NMR spectra of a series of Mo(CO)4((PPh2O)2Y(R)R′) (Y(R) = P(O), Si(Me); R′=alkyl, haloalkyl, aryl) and [Mo(CO)4(PPh2O)2]2Si complexes are given. The chemical shift ranges of the cis and trans carbonyl 13C and 17O, phenyl C(1) 13C and 31P resonances are relatively large and, with the exception of the cis carbonyl 17O chemical shifts, the correlations between the chemical shifts of the various resonances are excellent. These correlations are consistent with the model of metal carbonyl 13C and 17O chemical shifts proposed by Bodner and Todd. In addition they allow the model to be extended to include the diphenylphosphinite 31P chemical shifts in these complexes. The excellent correlations may be due to the presence of the chelate ring which limits the rotation around the molybdenum-phosphorus bond and to the fact that all three groups directly bonded to the phosphorus remains constant. 相似文献
15.
The reactions of [ReOX3(AsPh3)2] and [ReOX3(PPh3)2] with 2-(2′-hydroxyphenyl)-2-benzoxazoline (Hhbo) have been examined and [ReOX2(hbo)(AsPh3)] and [ReOX2(hbo)(PPh3)] (X = Cl, Br) complexes have been obtained. The crystal and molecular structures of [ReOCl2(hbo)(AsPh3)] (1) and [ReOBr2(hbo)(PPh3)] (4) have been determined. The electronic structures of 1 and 4 have been calculated with the density functional theory (DFT) method. The spin-allowed electronic transitions of 1 and 4 have been calculated with the time-dependent DFT method, and the UV–Vis spectra of these complexes have been discussed. 相似文献
16.
17.
Alireza Ariafard 《Journal of organometallic chemistry》2004,689(14):2275-2283
A set of phosphine complexes of the type W(CO)3(PX3)2(CH2CH2) (X=H, CH3, F, Cl, Br, and I) were investigated by density functional theory method (BP86) to examine the effect of the substituent X on the orientation of C-C vector of the ethylene ligand with respect to one of the metal-ligand bonds as well as the donation and the backdonation in the bonding ligands of phosphine and ethylene. When X=CH3, H, F, and Cl, the ethylene C-C vector prefers to be coplanar with metal-phosphine bonds, while for the ethylene complexes containing PBr3 and PI3 ligands, the structural preference is coplanarity of the ethylene and the metal-carbonyl bonds. The molecular orbital calculations and natural bond orbital analysis were used to examine the structural consequences derived from these complexes. It can be concluded that the structural preferences in the complexes have a clear relation to electronic effects of phosphine ligands. Our calculations for halide phosphine complexes, particularly for PBr3 and PI3, allow us to conclude that in addition to electronic effects, steric factors can also affect the orientation of the ethylene ligand in complexes. 相似文献
18.
Zinc(II) and mercury(II) thiocyanate complexes with nicotinamide, bis(nicotinamide-N)-bis(thiocyanato-N)zinc(II) (1) and catena-[nicotinamide-N-(μ-thiocyanato-S,N)(thiocyanato-S)mercury(II)] (2), have been prepared and characterized by spectroscopic, thermal and X-ray crystallographic methods. The vibrational bands of diagnostic value are compared to the values of the free ligand and the data are in good correlation with the X-ray results. Centrosymmetrical hydrogen bonded dimers are found, R22(10) in 1 and R22(8) in 2. 相似文献
19.
Alejandro J. Arce Rubn Machado Ysaura De Sanctis Raúl Isea Reinaldo Atencio Antony J. Deeming 《Journal of organometallic chemistry》1999,580(2):3519
The compound [Re2(CO)8(MeCN)2] reacts with diazoindene (C9H6N2) while refluxing in THF to afford three dirhenium products in which C9H6N2 is cleaved with loss of N2 and with incorporation of the residual indenylidene group into the products. Two indenylidene groups are coupled in two diastereomers of [Re2(CO)6(μ,η5:η5-1,1′-C18H12)] where C18H12=bis(indenylidene). X-ray structures show that these isomers are related as RR/SS and RS isomers. These have the two Re(CO)3 groups coordinated transoid and cisoid, respectively to a trans bis(indenylidene) bridge. The third product is the μ-indenylidene complex [Re2(CO)8(μ,η1:η5-C9H6)], which was also structurally characterised by X-ray diffraction. 相似文献
20.
Anvarhusein A. Isab Sidra Nawaz Muhammad Saleem Muhammad Altaf Muhammad Monim-ul-Mehboob Saeed Ahmad Helen Stoeckli Evans 《Polyhedron》2010
Mixed ligand silver(I) complexes of triphenylphosphine and thioureas (thiourea (Tu), N-methylthiourea (Metu), N,N′-dimethylthiourea (Dmtu) and N,N′-diethylthiourea (Detu)) with the general formulae, [(Ph3P)2Ag(thione)]NO3 and [(Ph3P)Ag(thione)2]NO3, have been prepared and characterized by elemental analysis, IR and NMR (1H, 13C and 31P) spectroscopic methods. The crystal structure of one of them has been determined by X-ray crystallography. The spectral data of the complexes are consistent with sulfur coordination of the thiones to silver(I). The single crystal X-ray structure of complex 1, {[Ag(PPh3)(thiourea)(NO3)]2·[Ag(PPh3)(thiourea)]2(NO3)2}, shows that the complex consists of two independent centrosymmetric binuclear units, each having the silver atoms coordinated to one PPh3 and two bridging thiourea molecules. In one of the independent units the silver atom is additionally bound to a nitrate ion, leading to a tetrahedral geometry, while in the other unit the silver atom adopts a trigonal planar environment. Antimicrobial activities of the complexes were evaluated by their minimum inhibitory concentration and the results showed that the complexes show a wide range of activity against two gram-negative bacteria (Escherichiacoli, Pseudomonasaeruginosa) and molds (Aspergillusniger, Penicilliumcitrinum), while the activities were poor against yeasts (Candidaalbicans, Saccharomycescerevisiae). However, the title complex did not show activity against any tested microorganism. 相似文献