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1.
The trichlorides of yttrium, samarium, and lutetium react with 2 equivalents of Na[C5H4 tBu] and 1 equivalent of NaBH4 to give [(η5-C5H4 tBu)2LnBH4(THF)] (Ln = Y ( 1 ), Sm ( 2 ), Lu ( 3 )) or with 2 equivalents of Na[C5Me4R] and 1 equivalent of NaBH4 to form [(η5-C5Me4R)2 · LnBH4(THF)] (R = H, Ln = Y ( 4 ), Sm ( 5 ), Lu ( 6 ); R = Me, Ln = Y ( 7 ), Sm ( 8 ), Lu ( 9 ); R = Et, Ln = Y ( 10 ), Sm ( 11 ), Lu ( 12 ); R = iPr, Ln = Y ( 13 ), Sm ( 14 ), Lu ( 15 )). The new compounds have been characterized by elemental analysis, NMR spectroscopy and mass spectrometry. The crystal structures of 8 and 10 were determined by single crystal X-ray diffraction.  相似文献   

2.
Organometallic Compounds of the Lanthanides. 113. [(tert-Butylcyclopentadienyl)(cyclopentadienyl)dimethylsilane] Complexes of selected Lanthanides The reaction of [Me2Si(C5H4)(tBuC5H3)]Li2 with LnCl3 (Ln = Y, Nd, Sm, Lu) in THF results in the formation of the chiral, dimeric complexes [Me2Si(C5H4)(tBuC5H3)]Ln(μ-Cl)2Li(THF)(Et2O) [Ln = Y ( 1 ), Nd ( 2 ), Sm ( 3 ), Lu ( 4 )]. The 1H-, 13C-NMR- and the mass spectra of the new compounds as well as the X-ray crystal structures of 2 a and 3 a were discussed.  相似文献   

3.
Organometallic Compounds of the Lanthanoids. 111. Synthesis and Characterization of Cationic Metallocene Complexes of the Lanthanoides. X-Ray Crystal Structure of [Cp Yb(THF)2][BPh4] Cationic organolanthanoide compounds [(C5H4R)2Sm(THF)2][BPh4] (R = tBu ( 1 ), SiMe3 ( 2 )), [PyrSm(THF)][BPh4] ( 3 ) (Pyr* = NC4H2tBu2-2,5), [CpLn(THF)2][BPh4] (Cp* = C5Me5; Ln = Y ( 4 ), Yb ( 5 )), and [(C5Me4Et)2 Ln(THF)2][BPh4] (Ln = Y ( 6 ), Sm ( 7 )) have been synthesized by oxidation of the divalent metallocenes [(C5H4R)2Sm(THF)2] (R = tBu, SiMe3), [PyrSm(THF)], [CpYb(THF), and [(C5Me4Et)2Sm(THF)] with Ag[BPh4] and by protolysis of the lanthanoide alkyls [CpYMe(THF)], [CpYbCH(SiMe3)2], and [(C5Me4Et)2LnCH(SiMe3)2] (Ln = Y, Sm) by [NEt3H][BPh4]. The 1H- and 13C-NMR spectra of the new compounds are discussed. 5 crystallizes in the space group P21/c with a = 10.604(7), b = 21.749(3), c = 19.124(4) Å, β = 96.47(4)°, Z = 4 and V = 4383(3) Å3 (R = 0.0291 for 8517 observed reflections with Fo ≥ 4σ (Fo).  相似文献   

4.
齐民华  沈琪等 《中国化学》2002,20(6):564-569
The reaction between K(1‐C5H9C9H6) and anhydrous LnCl3 (Ln=Sm, Yb) in the molar ratio of 2:1 in THF with subsequent treatment by Na‐K alloy afforded (1‐C5H9C9H6)2Ln‐(THF)n(Ln=Sm, n=1; Ln=Yb, n=2), while the reaction of Sml2 with K(1‐C5H9C9H6) in the molar ratio of 1:2 in THF gave the anionic complex K(1‐C5H9C9H6)3Sm(THF)3. The X‐ray structure of (1‐C5H9C9H6)2Yb(THF)2 showed that central metal Yb is coordinated by two cyclopentadienyl rings of 1‐cyclopentylindenyls and two oxygen atoms from two tetrahydrofuran molecules to form pseudo‐tetrahedral coordinate geometry. All these complexes are active for the polymerization of acrylonitrile.  相似文献   

5.
The heterobimetallic peralkylated complexes [Ln(AlR4)2]n (Ln = Sm, Yb; R = Me, Et) were synthesized by a silylamide elimination route from Ln[N(SiMe3)2]2(THF)2 and an excess of AlR3. The solid-state structure of [Sm(AlEt4)2]n is isomorphous to that of the ytterbium derivative. Polymeric [Yb(AlMe4)2]n was examined by 1H and 13C MAS NMR spectroscopy revealing the presence of distinct bridging methyl groups. The reaction of [Yb(AlMe4)2]n and 1,10-phenanthroline (Phen) afforded the monomeric donor adduct Yb(AlMe4)2(Phen), while the protonolysis reaction with 2 equiv. C5Me5H (HCp*) yielded a separated ion pair of composition [Cp*Yb(THF)(4)][AlMe(4)]. Single-crystal X-ray diffraction data are provided for both ytterbium(II) complexes. Solid-state magnetic measurements (SQUID) were performed on [Sm(AlMe4)2]n, [Sm(AlEt4)2]n, SmI2(THF)2 and Sm[N(SiMe3)2]2(THF)2 showing high effective magnetic moments 3.67micro(B) < micro(eff) < 4.43micro(B).  相似文献   

6.
于晓燕  金国新  翁林红 《中国化学》2002,20(11):1256-1262
IntroductionUptodateconsiderableattentionhasbeendevotedtothemetalcomplexeswithchalcogenolateligands .1,2Recentlytransitionmetalcomplexescontainingachelating1,2 dicarba closo dodecabarane 1,2 dichalcogenolatelig ands3 10 haveattractedagreatdealofinterestduetot…  相似文献   

7.
The reactivity of the mono(pentamethylcyclopentadienyl) divalent lanthanide tetraphenylborate complexes, (C5Me5)Ln(BPh4) (Ln = Sm, 1; Yb, 2), was investigated to determine how Ln2+ and (BPh4)1? reactivity would combine in these species. The (BPh4)1? ligand in (C5Me5)Yb(BPh4) can be displaced with KN(SiMe3)2 to form the heteroleptic divalent dimer, {(C5Me5)Yb[μ-N(SiMe3)2]}2 (3). Both 1 and 2 reduce phenazine to give the bis(pentamethylcyclopentadienyl) ligand redistribution products, [(C5Me5)2Ln]2(μ-C12H8N2). 2,2-Bipyridine is reduced by 1 to yield the ligand redistribution product, (C5Me5)2Sm(C10H8N2) (4), while 2 does not react with bipyridine. Tert-butyl chloride is reduced by 1 to form the trimetallic pentachloride complex [{(C5Me5)(THF)Sm}3(μ-Cl)5][BPh4] (6), in a reaction that appears to use the reductive capacity of both Sm2+ and (BPh4)1?.  相似文献   

8.
9.
The preparation and characterization of a series of neutral rare‐earth metal complexes [Ln(Me3TACD)(η3‐C3H5)2] (Ln=Y, La, Ce, Pr, Nd, Sm) supported by the 1,4,7‐trimethyl‐1,4,7,10‐tetraazacyclododecane anion (Me3TACD?) are reported. Upon treatment of the neutral allyl complexes [Ln(Me3TACD)(η3‐C3H5)2] with Brønsted acids, monocationic allyl complexes [Ln(Me3TACD)(η3‐C3H5)(thf)2][B(C6X5)4] (Ln=La, Ce, Nd, X=H, F) were isolated and characterized. Hydrogenolysis gave the hydride complexes [Ln(Me3TACD)H2]n (Ln=Y, n=3; La, n=4; Sm). X‐ray crystallography showed the lanthanum hydride to be tetranuclear. Reactivity studies of [Ln(Me3TACD)R2]n (R=η3‐C3H5, n=0; R=H, n=3,4) towards furan derivatives includes hydrosilylation and deoxygenation under ring‐opening conditions.  相似文献   

10.
Amido Ligands for the Synthesis of Polynuclear Lanthanoid Complexes By 1 : 1 reaction of LnBr3 with NaNHPh in THF the Rare-Earth Complexes [Ln2Br42-NHPh)2(thf)5] (Ln = Sm ( 1 ), Ln = Gd ( 2 )) with two bridging anilido ligands are obtained. In the system LnBr3/NaNHPh/(Me2SiO)3 the tetranuclear compounds [Ln44-O)(NHPh)3(OSiMe2NPh)6Na5(thf)7] · THF (Ln = Gd ( 3 ), Ln = Yb ( 4 )) can be built up. They have a central μ4-oxygene atom in the Ln4-tetrahedron. It has an oxa-dimethylsilyl-N-phenylamido ligand over all edges and an anilido ligand on three vertexes. By this reaction small amount of [Na4(thf)6Yb2(OSiMe2NPhSiMe2O)2(OSiMe2NPh)2(NHPh)2] ( 5 ) with a O- and N-bridged Yb–Na polyhedron and N-phenyl-bis(dimethylsilanolato)-ligands coordinating μ22 with its oxygen atoms are obtained. Reaction of Lanthanideshalides with LiNHtBu leads to dimeric complexes. The formation of bridging oxasilylamido ligands is also observed. The compound [Li2Ln(OSiMe2NtBu)2(HNtBu)(thf)]2 (Ln=Sm ( 6 ), Gd ( 7 ) and Yb ( 8 )) contains now an O- and N-bridged Ln–Li polyhedron. (Crystal Data of 1–8 see ‘‘Inhaltsverzeichnis”︁”︁).  相似文献   

11.
[Ln[N(SiMe3)2]2(THF)2](Ln = Sm, Yb) reacts with 1 equiv. of carbon-bridged biphenols, 2,2'-methylene-bis(6-tert-butyl-4-methylphenol)(L1H2) or 2,2'-ethylidene-bis(4,6-di-tert-butylphenol)(L2H2), in toluene to give the novel aryloxide lanthanide(II) complexes [[LnL1(THF)n]2](Ln = Sm, n = 3 (1); Ln = Yb, n = 2 (2)) and [[LnL2(THF)3]2](Ln = Sm (5); Ln = Yb (6)) in quantitative yield, respectively. Addition of 2 equiv. of hexamethylphosphoric triamide (HMPA) to a tetrahydrofuran (THF) solution of 1, 2 and 5 affords the corresponding HMPA-coordinated complexes, [[LnL1(THF)m(HMPA)n]2(THF)y](Ln = Sm, n = 2, m = 0, y = 2 (3); Ln = Yb, m = 1, n = 1, y = 6 (4)) and [[SmL2(HMPA)2]2](7) in excellent yields. The single-crystal structural analyses of 3, 4 and 7 revealed that these aryloxide lanthanide(II) complexes are dimeric with two Ln-O bridges. The coordination geometry of each lanthanide metal can be best described as a distorted trigonal bipyramid. Complexes 1-3, 5 and 7 can catalyze the ring-opening polymerization of epsilon-caprolactone (epsilon-CL), and 1-3, along with 5 show moderate activity for the ring-opening polymerization of 2,2-dimethyltrimethylene carbonate (DTC) and the copolymerization of epsilon-CL and DTC to give random copolymers with high molecular weights and relatively narrow molecular weight distributions..  相似文献   

12.
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   

13.
Reaction of LnCl3 first with three equivalent of C5H5Na in THF, then with one equivalent of N‐phenyldiethanolamine in THF‐DME afforded complexes of {[(C5H5)Ln((‐OCH2CH2)2N(C6H5)]4((4‐Cl)}[Na(DME)4] (Ln=Sm ( 1 ), Yb ( 2 )), being characterized by infrared spectra, elemental analyses and X‐ray crystallography. They are ionic pair compounds. The anionic part is a cluster, which can be viewed as a cyclic tetramer with four (C5H5)Ln units bridged by four pairs of OR groups, forming a pinwheel structure. Both the complexes can catalyze the ring‐opening polymerization of ε‐caprolactone under mild conditions, and complex 1 is more active than complex 2 . The polymerization accords with one order reaction kinetics for monomer concentration. The molecular weight increases with the yield increasing, and the molecular weight distribution is rather narrow (1.19相似文献   

14.
A series of rare earth metal amido complexes bearing methylene‐linked pyrrolyl‐amido ligands were prepared through silylamine elimination reactions and displayed high catalytic activities in hydrophosphonylations of aldehydes and unactivated ketones under solvent‐free conditions for liquid substrates. Treatment of [(Me3Si)2N]3Ln(μ‐Cl)Li(THF)3 with 2‐(2,6‐Me2C6H3NHCH2)C4H3NH ( 1 , 1 equiv) in toluene afforded the corresponding trivalent rare earth metal amides of formula {(μ‐η51):η1‐2‐[(2,6‐Me2C6H3)NCH2](C4H3N)LnN(SiMe3)2}2 [Ln=Y ( 2 ), Nd ( 3 ), Sm ( 4 ), Dy ( 5 ), Yb ( 6 )] in moderate to good yields. All compounds were fully characterized by spectroscopic methods and elemental analyses. The yttrium complex was also characterized by 1H NMR spectroscopic analyses. The structures of complexes 2 , 3 , 4 , and 6 were determined by single‐crystal X‐ray analyses. Study of the catalytic activities of the complexes showed that these rare earth metal amido complexes were excellent catalysts for hydrophosphonylations of aldehydes and unactivated ketones. The catalyzed reactions between diethyl phosphite and aldehydes in the presence of the rare earth metal amido complexes (0.1 mol %) afforded the products in high yields (up to 99 %) at room temperature in short times of 5 to 10 min. Furthermore, the catalytic addition of diethyl phosphite to unactivated ketones also afforded the products in high yields of up to 99 % with employment of low loadings (0.1 to 0.5 mol %) of the rare earth metal amido complexes at room temperature in short times of 20 min. The system works well for a wide range of unactivated aliphatic, aromatic or heteroaromatic ketones, especially for substituted benzophenones, giving the corresponding α‐hydroxy diaryl phosphonates in moderate to high yields.  相似文献   

15.
Six new ethylthioethylcyclopentadienyl containing organolanthanide complexes CpLnCl [Ln=Gd (1), Dy (2)] and Cp2LnCpTh [Cp=C5H5, Ln=Yb (3), Sm (4), Dy (5), Y (6)] were synthesized by the reaction of ethylthioethyl‐cyclopentadienyl (CpTh) sodium salt with LnCl3 or Cp2LnCl in THF. Complexes 1–6 were characterized by elemental analyses, infrared and mass spectroscopies. The molecular structures of complexes 1–3 were also determined by the X‐ray single crystal diffraction. The results show that the side‐chain sulfur atom on the ethylthioethylcyclopentadienyl ring can form intramolecular chelating coordination to the central lanthanide ion, improving the stability of organolanthanide complexes and reducing the number of coordinated THF molecules.  相似文献   

16.
Discrete ion-pair complexes [Ln(EDBP)2(DME)Na(DME)3] [Ln=Er (1), Yb (2), Sm (3)] have been synthesized by the reaction between sodium salt of 2,2′-ethylidene-bis(4,6-di-tert-butylphenol)(EDBPH2) and Ln(BH4)3·3THF (Ln=Er, Yb, Sm) followed by centrifugation and recrystalization. The complexes were characterized by elemental analysis and FT-IR, and the bonding model of these compounds was confirmed by X-ray single crystal diffraction for complex 1. It was found that four O atoms in two biphenol ligands as well as two O atoms in one ethylene glycol dimethyl ether (DME) molecule connect to the center rare earth metal atom, while sodium exists as counterpart cation to balance the charge. Complexes 1–3 can all be used as single component initiators for the ring-opening polymerization of ɛ-caprolactone.  相似文献   

17.
The synthesis and characterization of dimeric lanthanide amides stabilized by a dianionic N‐aryloxo functionalized β‐ketoiminate ligand are described in this paper. Reactions of 4‐(2‐hydroxy‐5‐tert‐butyl‐phenyl)imino‐2‐pentanone (LH2) with Ln[N(SiMe3)2]3(µ‐Cl)Li(THF)3 in a 1:1 molar ratio in THF gave the dimeric lanthanide amido complexes [LLn{N(SiMe3)2}(THF)]2 [Ln=Nd ( 1 ), Sm ( 2 ), Yb ( 3 ), Y ( 4 )] in good isolated yields. These complexes were characterized by IR spectroscopy, elemental analysis, and 1H NMR spectroscopy in the case of complex 4 . The definitive molecular structures of complexes 1 , 3 , and 4 were determined. It was found that complexes 1 to 4 can initiate the ring‐opening polymerization of L‐lactide.  相似文献   

18.
In this paper, we report the first examples of trispyrazolylmethane complexes of rare earths. Reaction of LnCl3 with Tpm* (tris(3,5-dimethylpyrazolyl)methane) in THF or acetonitrile gives good yields of the [Ln(Tpm*)Cl3] (Ln = Y, Ce, Nd, Sm, Gd, Yb). Tpm* adducts of the lanthanide triflates [Ln(Tpm*)(OTf)3(THF)] (Ln = Y, Ho, Dy) may also be prepared. The X-ray crystal structures of [Y(Tpm*)Cl3], [Sm(Tpm*)Cl3(THF)], and [Ln(Tpm*)(OTf)3(THF)] (Ln = Y, Ho) are reported. The halide/triflate complexes may be used to prepare the aryloxide complexes [Ln(Tpm*)(OArMe2)3] (Ln = Y, Nd, Sm, Yb; ArMe2 = C6H3-2,6-(CH3)2), which are fluxional in solution as a result of interactions between the Tpm* and the aryloxide groups. The structures of the Nd and Sm complexes have been determined. Finally, the reaction of [Nd(BH4)3(THF)3] with Tpm* in THF results in the displacement of two THF molecules to give [Nd(Tpm*)(BH4)3(THF)]. Infrared spectra are consistent with tridentate borohydride coordination. The X-ray structures of these compounds indicate that the Tpm* ligand is less strongly bound than its anionic trispyrazolylborate analogues.  相似文献   

19.
Two types of isostructural complexes of lanthanide chlorides with diglyme have been synthesized. These are mononuclear molecular complexes [LnCl3(diglyme)(THF)] (Ln = Eu ( 1 ), Gd ( 2 ), Dy ( 3 ), Er ( 4 ), Yb ( 5 ); diglyme = diethylen glycol dimethyl ether) and binuclear molecular complexes [LnCl3(diglyme)]2 (Ln = Dy ( 3d ), Er ( 4d ), Yb ( 5d )). Complex 1 was obtained by the reaction of [EuCl3(DME)2] with diglyme in THF. The complexes 2 – 5 and 3d – 5d resulted from reactions of LnCl3·6H2O, (CH3)3SiCl and diglyme in THF. The mononuclear complexes 2 – 5 crystallized directly from the solutions where the reactions of lanthanide compounds with diglyme took place. Recrystallizations of the powder products of the same reactions from dichloromethane resulted in the binuclear complexes 3d – 5d . Reactions of lanthanide bromide hydrates, (CH3)3SiBr and diglyme in THF achieved mononuclear molecular complexes [LnBr3(diglyme)(L)] (Ln = Gd, L = H2O ( 6 ); Ln = Ho, L = THF ( 7 )). Crystals of 6 and 7 were grown by recrystallization from dichloromethane. The lanthanide atoms (Ln = Eu–Yb) are seven‐coordinated in a distorted pentagonal bipyramidal fashion in all reported complexes, 1 – 7 and 3d – 5d . Four oxygen atoms and three halide ions are coordinated to lanthanide atoms in 1 – 7 , [LnX3(diglyme)(L)]. Four chloride ions, two bridging and two nonbridging, and three oxygen atoms are coordinated to lanthanide atoms in 3d – 5d , [LnCl3(diglyme)]2.  相似文献   

20.
Organometallic Compounds of the Lanthanides. 155 [1] Synthesis and Characterization of New Lanthanocene Complexes containing Silylated Cyclopentadienyl Ligands The trichlorides of yttrium, samarium, and lutetium react with two equiv. of K[C5H4SiEt3] ( 1 ) to form the dimeric compounds [(η5‐C5H4SiEt3)2LnCl]2 (Ln = Y ( 2 ), Sm ( 3 ), Lu ( 4 )). These react with one equiv. of methyllithium to give the corresponding dimeric lanthanocenemethyl complexes [(η5‐C5H4SiEt3)2LnMe]2 (Ln = Y ( 5 ), Sm ( 6 ), Lu ( 7 )). The reaction between samarium trichloride and lutetium trichloride, respectively with two equiv. of K[1, 3‐C5H3(SiMe3)2] followed by one equiv. of methyllithium results in the formation of the monomeric methyl complexes [η5‐1, 3‐C5H3(SiMe3)2]2LnMe(THF) (Ln = Sm ( 8 ), Lu ( 9 )). The new compounds have been characterized by elemental analysis, mass spectrometry, 1H‐ and 13C{1H} NMR spectroscopy, as well as 1 — 7 by single crystal X‐ray structure analysis.  相似文献   

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