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1.
Only a few cyclooctatetraene dianion (COT) π‐complexes of lanthanides have been crystallographically characterized. This first single‐crystal X‐ray diffraction characterization of a scandium(III) COT chloride complex, namely di‐μ‐chlorido‐bis[(η8‐cyclooctatetraene)(tetrahydrofuran‐κO )scandium(III)], [Sc2(C8H8)2Cl2(C4H8O)2] or [Sc(COT)Cl(THF)]2 (THF is tetrahydrofuran), (1), reveals a dimeric molecular structure with symmetric chloride bridges [average Sc—Cl = 2.5972 (7) Å] and a η8‐bound COT ligand. The COT ring is planar, with an average C—C bond length of 1.399 (3) Å. The Sc—C bond lengths range from 2.417 (2) to 2.438 (2) Å [average 2.427 (2) Å]. Direct comparison of (1) with the known lanthanide (Ln) analogues (La, Ce, Pr, Nd, and Sm) illustrates the effect of metal‐ion (M ) size on molecular structure. Overall, the M —Cl, M —O, and M —C bond lengths in (1) are the shortest in the series. In addition, only one THF molecule completes the coordination environment of the small ScIII ion, in contrast to the previously reported dinuclear Ln–COT–Cl complexes, which all have two bound THF molecules per metal atom.  相似文献   

2.
The title compound, [Cu(C9H5N2O3)2(C2H6OS)2], consists of octahedrally coordinated CuII ions, with the 3‐oxo‐3,4‐dihydroquinoxaline‐2‐carboxylate ligands acting in a bidentate manner [Cu—O = 1.9116 (14) Å and Cu—N = 2.1191 (16) Å] and a dimethyl sulfoxide (DMSO) molecule coordinated axially via the O atom [Cu—O = 2.336 (5) and 2.418 (7) Å for the major and minor disorder components, respectively]. The whole DMSO molecule exhibits positional disorder [0.62 (1):0.38 (1)]. The octahedron around the CuII atom, which lies on an inversion centre, is elongated in the axial direction, exhibiting a Jahn–Teller effect. The ligand exhibits tautomerization by H‐atom transfer from the hydroxyl group at position 3 to the N atom at position 4 of the quinoxaline ring of the ligand. The complex molecules are linked through an intermolecular N—H...O hydrogen bond [N...O = 2.838 (2) Å] formed between the quinoxaline NH group and a carboxylate O atom, and by a weak intermolecular C—H...O hydrogen bond [3.392 (11) Å] formed between a carboxylate O atom and a methyl C atom of the DMSO ligand. There is a weak intramolecular C—H...O hydrogen bond [3.065 (3) Å] formed between a benzene CH group and a carboxylate O atom.  相似文献   

3.
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   

4.
Reaction of [U(TrenTIPS)(THF)][BPh4] ( 1 ; TrenTIPS=N{CH2CH2NSi(iPr)3}3) with NaPH2 afforded the novel f‐block terminal parent phosphide complex [U(TrenTIPS)(PH2)] ( 2 ; U–P=2.883(2) Å). Treatment of 2 with one equivalent of KCH2C6H5 and two equivalents of benzo‐15‐crown‐5 ether (B15C5) afforded the unprecedented metal‐stabilized terminal parent phosphinidene complex [U(TrenTIPS)(PH)][K(B15C5)2] ( 4 ; U?P=2.613(2) Å). DFT calculations reveal a polarized‐covalent U?P bond with a Mayer bond order of 1.92.  相似文献   

5.
In the title compound, [Li(C4H8O)4][ZrCl2(C12H8N)3(C4H8O)], the environment of the Zr atom is pseudo‐octahedral, with the three carbazolyl ligands in a mer configuration. The counter‐ion of the zirconium complex is composed of an Li atom surrounded by four tetra­hydro­furan (THF) mol­ecules. The THF mol­ecule attached to the Zr atom is disordered over two sites, as are two of the THF mol­ecules in the lithium moiety. All bond distances and angles are consistent with those in complexes with similar structural entities. The Zr—N bond distances are 2.2185 (18) and 2.167 (3) Å.  相似文献   

6.
A new cyano‐bridged binuclear 4f‐3d complex Sm(DMSO)4‐(H2O)3Cr(CN)6 was synthesized and characterized by single crystal structure analysis. It crystallizes in monoclinic, space group P21 with a=0.9367(2) nm, b = 1.3917(3) nm, c = 1.1212(2) run, β = 99.88(3)° and Z = 2. In this binuclear complex, Sm atom is eight coordinated and linked to the Cr atom by a cyano bridge. The molecules packs to form 3D structure due to the hydrogen bonds among them. [K3(18‐C‐6)3(H2O)4]Cr(CN)6·3H2O (18‐C‐6 represents 18‐crown‐6‐ether) that was synthesized as a byproduct in the preparation of a Gd—Cr complex is also structurally characterized. Crystal data: triclinic, space group P‐l with a = 1.0496(7) nm, b= 1.1567(14) nm, c = 1.3530(13) nm, a = 94.15(9)°, β = 96.04(8)°, γ = 95.25(9)° and Z = l. [K3(18‐C‐6)3(H2O)4]‐Cr(CN)6·3H2O consists of ionic [K3(18‐C‐6)3(H2O)4]3+ and [Cr(CN)6]3‐ pairs, of which the [K3(18‐C‐6)3(H2O)4]3+ ion is a trinuclear duster connected by water, and K atoms are eight coordinated by eight oxygen atoms of one 18‐C‐6 and two water molecules.  相似文献   

7.
The potassium dihydrotriazinide K(LPh,tBu) ( 1 ) was obtained by a metal exchange route from [Li(LPh,tBu)(THF)3] and KOtBu (LPh,tBu = [N{C(Ph)=N}2C(tBu)Ph]). Reaction of 1 with 1 or 0.5 equivalents of SmI2(thf)2 yielded the monosubstituted SmII complex [Sm(LPh,tBu)I(THF)4] ( 2 ) or the disubstituted [Sm(LPh,tBu)2(THF)2] ( 3 ), respectively. Attempted synthesis of a heteroleptic SmII amido‐alkyl complex by the reaction of 2 with KCH2Ph produced compound 3 due to ligand redistribution. The YbII bis(dihydrotriazinide) [Yb(LPh,tBu)2(THF)2] ( 4 ) was isolated from the 1:1 reaction of YbI2(THF)2 and 1 . Molecular structures of the crystalline compounds 2 , 3· 2C6H6 and 4· PhMe were determined by X‐ray crystallography.  相似文献   

8.
袁福根  刘秀娟  张勇 《中国化学》2005,23(6):749-752
Reaction of divalent (Ph2N)2Sm(THF)4 with 1 equiv, of azobenzene in THF and then crystallization of the product in DME-Et2O mixed solvent produced the complex of [(PhEN)(DME)Sm]E(μ-η^2:η^2-N2Ph2)2 (1) in 65.0% yield. In complex 1, azobenzene molecules were reduced to be dianionic Ph2N2^2- ligands, bridging two samarium ions in two η^2:η^2 fashions. One samarium ion was bonded to a DME molecule and a diphenyl amido ligand besides two Ph2N2^2- ligands. The unusual Ln-η^2-arene close interaction was found for the first time for diphenyl amido lanthanides. Complex 1 could catalyze the polymerization of methyl methacrylate and acrylonitrile  相似文献   

9.
(PPh4)2[(SN)ReCl3(μ‐N)(μ‐NSN)ReCl3(THF)] – a Nitrido‐Thionitrosyl‐Dinitridosulfato‐Complex of Rhenium The title compound has been prepared from PPh4[ReVIICl4(NSCl)2] with excess N(SiMe3)3 in dichloromethane solution to give red‐brown single crystals after recrystallisation from acetonitrile/THF solutions. As a by‐product PPh4[ReNCl4] is formed. (PPh4)2[(SN)ReCl3(μ‐N)(μ‐NSN)ReCl3(THF)] ( 1 ): Space group P21/n, Z = 4, lattice dimensions at –80 °C: a = 1024.1(1), b = 2350.2(1), c = 2315.4(2) pm, β = 94.09(1)°, R1 = 0.0403. In the complex anion of 1 the rhenium atoms are connected by an asymmetric Re≡N–Re bridge as well as by a (NSN)4–‐bridge to form a planar Re2N(NSN) six‐membered heterocycle. Both rhenium atoms are coordinated by three chlorine atoms, one of them by a thionitrosyl ligand, the other one by the oxygen atom of a thf molecule.  相似文献   

10.
The N‐heterocyclic carbene, 1,3‐dimesityl‐imidazol‐2‐ylidene (IMes) reacts with tetrahydrofuran (THF) in the presence of an oxidizing uranyl triflate complex, UO2(OTf)2(thf)3 (?OTf = ?OSO2CF3), to give 1,4‐bis(1,3‐dimesityl‐2‐imidazolium)‐1,3‐butadiene bis(trifluoromethanesulfonate), formally understood as the coupling product of two equivalents of IMes with [CH?CH? CH?CH](OTf)2. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

11.
The crystal structures of tris(2‐methyl­quinolin‐8‐olato‐N,O)­iron(III), [Fe­(C10­H8­NO)3], (I), and aqua­bis(2‐methyl­quinolin‐8‐olato‐N,O)­copper(II), [Cu­(C10­H8NO)2­(H2O)], (II), have been determined. Compound (I) has a distorted octahedral configuration, in which the central Fe atom is coordinated by three N atoms and three O atoms from three 2‐methylquinolin‐8‐olate ligands. The three Fe—O bond distances are in the range 1.934 (2)–1.947 (2) Å, while the three Fe—N bond distances range from 2.204 (2) to 2.405 (2) Å. In compound (II), the central CuII atom and H2O group lie on the crystallographic twofold axis and the coordination geometry of the CuII atom is close to trigonal bipyramidal, with the three O atoms in the basal plane and the two N atoms in apical positions. The Cu—N bond length is 2.018 (5) Å. The Cu—O bond length in the basal positions is 1.991 (4) Å, while the Cu—O bond length in the apical position is 2.273 (6) Å. There is an intermolecular OW—H?O hydrogen bond which links the mol­ecules into a linear chain along the b axis.  相似文献   

12.
Neutral binuclear ruthenium complexes 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 of the general formula [{RuCl26p‐cym)}2 μ‐(NN)] (NN = bis(nicotinate)‐ and bis(isonicotinate)‐polyethylene glycol esters: (3‐py)COO(CH2CH2O)nCO(3‐py) and (4‐py)COO(CH2CH2O)nCO(4‐py), n =1–4), as well as mononuclear [RuCl26p‐cym)((3‐py)COO(CH2CH2OCH3)‐κN)], complex 9 , were synthesized and characterized using elemental analysis and electrospray ionization high‐resolution mass spectrometry, infrared, 1H NMR and 13C NMR spectroscopies. Stability of the binuclear complexes in the presence of dimethylsulfoxide was studied. Furthermore, formation of a cationic complex containing bridging pyridine‐based bidentate ligand was monitored using 1H NMR spectroscopy. Ligand precursors, polyethylene glycol esters of nicotinic ( L1 · 2HCl– L4 · 2HCl and L9 · HCl) and isonicotinic acid dihydrochlorides ( L5 · 2HCl– L8 · 2HCl), binuclear ruthenium(II) complexes 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 and mononuclear complex 9 were tested for in vitro cytotoxicity against 518A2 (melanoma), 8505C (anaplastic thyroid cancer), A253 (head and neck tumour), MCF‐7 (breast tumour) and SW480 (colon carcinoma) cell lines. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

13.
The reaction of PhN3(H)C6H4N3(H)Ph with Hg(NO3)2 in THF in the presence of triethylamine yields {Hg[PhN3C6H4N3(H)Ph](NO3)} as a yellow powder that can be recrystallized from THF/acetone. The crystals belong to the monoclinic system, space group P21 with the cell dimensions a = 9.639(2), b = 5.412(1), c = 19.675(4) Å, β= 97.47(3)°, V = 1017.7 (4) Å3, Z = 2. The crystal structure determination (2668 unique reflections with [I>2σ(I)], 262 parameters, R1 = 0.0393) shows that the structure consists of mononuclear complexes. Hg atoms are linearly coordinated by one Nα atom of the triazenide unit of the planar ligand [Hg‐N(1) = 2.101(8) Å] and an O atom of the NO3 ion [Hg‐O(1) = 2.11(1) Å]. Additional weak Hg‐N contacts [Hg‐N(4) = 2.662(9) and Hg‐N(3) = 2.851(9) Å] and an intramolecular hydrogen bond between the triazenide hydrogen and an O atom of the nitrate group are observed [N(6)‐H(6)···O(2) = 2.92(2) Å]. The complexes are stacked to infinite chains by metal‐arene π‐interactions. Each Hg atom is coordinated by the terminal phenyl rings of two neighboring complexes [Hg‐C from 3.40(1) to 4.10(1) Å] in a η2 fashion.  相似文献   

14.
The synthesis, structures and catalytic activities of three organolanthanide complexes supported by the H3tpa ligand (H3tpa = tris(pyrrolyl‐α‐methyl) amine) are described. Treatment of H3tpa with one equivalent of Ln[N(SiMe3)2]3 (Ln = Sc, Sm, Dy) in THF gives, after recrystallization from toluene/THF solution, Sc(tpa)(THF)2 ( 1 ), Sm(tpa)(THF)3 ( 2 ) and Dy(tpa)(THF)3 ( 3 ) in good yields. The structures of complexes 1 – 3 were determined by single‐crystal X‐ray diffraction and elemental analysis. Complexes 2 and 3 exhibited good catalytic activity for the polymerization of ?‐caprolactone.  相似文献   

15.
Methoxy‐modified β‐diimines HL 1 and HL 2 reacted with Y(CH2SiMe3)3(THF)2 to afford the corresponding bis(alkyl)s [L1Y(CH2SiMe3)2] ( 1 ) and [L2Y(CH2SiMe3)2] ( 2 ), respectively. Amination of 1 with 2,6‐diisopropyl aniline gave the bis(amido) counterpart [L1Y{N(H)(2,6‐iPr2? C6H3)}2] ( 3 ), selectively. Treatment of Y(CH2SiMe3)3(THF)2 with methoxy‐modified anilido imine HL 3 yielded bis(alkyl) complex [L3Y(CH2SiMe3)2(THF)] ( 4 ) that sequentially reacted with 2,6‐diisopropyl aniline to give the bis(amido) analogue [L3Y{N(H)(2,6‐iPr2? C6H3)}2] ( 5 ). Complex 2 was “base‐free” monomer, in which the tetradentate β‐diiminato ligand was meridional with the two alkyl species locating above and below it, generating tetragonal bipyramidal core about the metal center. Complex 3 was asymmetric monomer containing trigonal bipyramidal core with trans‐arrangement of the amido ligands. In contrast, the two cis‐located alkyl species in complex 4 were endo and exo towards the O,N,N tridentate anilido‐imido moiety. The bis(amido) complex 5 was confirmed to be structural analogue to 4 albeit without THF coordination. All these yttrium complexes are highly active initiators for the ring‐opening polymerization of L ‐LA at room temperature. The catalytic activity of the complexes and their “single‐site” or “double‐site” behavior depend on the ligand framework and the geometry of the alkyl (amido) species in the corresponding complexes. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5662–5672, 2007  相似文献   

16.
In the title complex, [Mn(C5H4NO)2(C5H5NO)2]n or [Mn(μ‐3‐PyO)2(3‐PyOH)2]n (3‐PyO is the pyridin‐3‐olate anion and 3‐PyOH is pyridin‐3‐ol), the MnII atom lies on an inversion centre and has octahedral geometry, defined by two N atoms and two deprotonated exocyclic O atoms of symmetry‐related pyridin‐3‐olate ligands [Mn—N = 2.3559 (14) Å and Mn—O = 2.1703 (11) Å], as well as two N atoms of terminal 3‐PyOH ligands [Mn—N = 2.3482 (13) Å]. The MnII atoms are bridged by the deprotonated pyridin‐3‐olate anion into a layer structure, generating sheets in the (01) plane. These sheets are linked by O—H⋯O hydrogen bonds. There are also π–π and C—H⋯π interactions in the crystal structure.  相似文献   

17.
In the title compound, 4‐iodoanilinium 2‐carboxy‐6‐nitrobenzoate, C6H7IN+·C8H4NO6, the anions are linked by an O—H...O hydrogen bond [H...O = 1.78 Å, O...O = 2.614 (3) Å and O—H...O = 171°] into C(7) chains, and these chains are linked by two two‐centre N—H...O hydrogen bonds [H...O = 1.86 and 1.92 Å, N...O = 2.700 (3) and 2.786 (3) Å, and N—H...O = 153 and 158°] and one three‐centre N—H...(O)2 hydrogen bond [H...O = 2.02 and 2.41 Å, N...O = 2.896 (3) and 2.789 (3) Å, N—H...O = 162 and 105°, and O...H...O = 92°], thus forming sheets con­taining R(6), R(8), R(13) and R(18) rings.  相似文献   

18.
Reaction of dichloro‐ and dibromodimethyltin(IV) with 2‐(pyrazol‐1‐ylmethyl)pyridine (PMP) afforded [SnMe2Cl2(PMP)] and [SnMe2Br2(PMP)] respectively. The new complexes were characterized by elemental analysis and mass spectrometry and by IR, Raman and NMR (1H, 13C) spectroscopies. Structural studies by X‐ray diffraction techniques show that the compounds consist of discrete units with the tin atom octahedrally coordinated to the carbon atoms of the two methyl groups in a trans disposition (Sn? C = 2.097(5), 2.120(5) Å and 2.110(6), 2.121(6) Å in the chloro and in the bromo compounds respectively), two cis halogen atoms (Sn? Cl = 2.4908(16), 2.5447(17) Å; Sn? Br = 2.6875(11), 2.7464(9) Å) and the two donor atoms of the ligand (Sn? N = 2.407(4), 2.471(4) Å and 2.360(5), 2.455(5) Å). In both cases, the Sn? N(pyridine) bond length is markedly longer than the Sn? N(pyrazole) distance. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

19.
The title compound, [Ni(C7H5O3)2(C10H24N4)], contains octahedral NiII in a centrosymmetric trans configuration with Ni—N distances of 2.0637 (17) and 2.0699 (16) Å and an Ni—O distance of 2.1100 (14) Å. The mol­ecules are linked by a single type of O—H?O hydrogen bond [O?O 2.618 (2) Å and O—H?O 161°] into two‐dimensional sheets; a singletype of N—H?O hydrogen bond [N?O 2.991 (2) Å and N—H?O 139°] links these sheets into a three‐dimensional framework.  相似文献   

20.
The bimetallic title complex, [CuFe(CN)5(C12H30N6O2)(NO)] or [Cu(L)Fe(CN)5(NO)] [where L is 1,8‐bis(2‐hydroxy­ethyl)‐1,3,6,8,10,13‐hexa­aza­cyclo­tetra­decane], has a one‐dimensional zigzag polymeric –Cu(L)–NC–Fe(NO)(CN)3–CN–Cu(L)– chain, in which the CuII and FeII centres are linked by two CN groups. In the complex, the CuII ion is coordinated by four N atoms from the L ligand [Cu—N(L) = 1.999 (2)–2.016 (2) Å] and two cyanide N atoms [Cu—N = 2.383 (2) and 2.902 (3) Å], and has an elongated octahedral geometry. The FeII centre is in a distorted octahedral environment, with Fe—N(nitroso) = 1.656 (2) Å and Fe—C(CN) = 1.938 (3)–1.948 (3) Å. The one‐dimensional zigzag chains are linked to form a three‐dimensional network via N—H⋯N and O—H⋯N hydrogen bonds.  相似文献   

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