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1.
Synthesis and Structure of Tetrameric Tris(trimethylsilyl)indium(I) and of New Silyl substituted Indium Compounds The reaction of InCp* with [LiSi(SiMe3)3·3thf] yielded in the first silylsubstituted tetrahedrane of indium [In4{Si(SiMe3)3}4] ( 1 ). It crystallizes together with [In{Si(SiMe3)3}3] ( 2 ) in dark green crystals. Colourless crystals of [Li(OH)(OSiMe3)In{Si(SiMe3)3}2]2 ( 3 ) were isolated as a byproduct from this reaction. It's structural core are three connected four membered rings made up of In‐, Li‐ and O‐atoms. From the reaction of [InOSO2CF3] with [LiSi(SiMe3)3·3thf] colourless crystals of [In{Si(SiMe3)3}2OSO2CF3·thf] ( 4 ) were isolated. InCp* reacted with [LiSiMe(SiMe3)2·3thf] to form the orange‐coloured monoindane [In{SiMe(SiMe3)2}3] ( 5 ). 1 – 4 were characterized by X‐ray crystal structure analyses.  相似文献   

2.
Three new complexes with phosphanylphosphido ligands, [Cu4{μ2‐P(SiMe3)‐PtBu}4] ( 1 ), [Ag4{μ2‐P(SiMe3)‐PtBu2}4] ( 2 ) and [Cu{η1‐P(SiMe3)‐PiPr2}2]–[Li(Diglyme)2]+ ( 3 ) were synthesized and structurally characterized by X‐ray diffraction, NMR spectroscopy, and elemental analysis. Complexes 1 and 2 were obtained in the reactions of lithium derivative of diphosphane tBu2P‐P(SiMe3)Li · 2.7THF with CuCl and [iBu3PAgCl]4, respectively. The X‐ray diffraction analysis revealed that the complexes 1 and 2 present macrocyclic, tetrameric form with Cu4P4 and Ag4P4 core. Complex 3 was prepared in the reaction of CuCl with a different derivative of lithiated diphosphane iPr2P‐P(SiMe3)Li · 2(Diglyme). Surprisingly, the X‐ray analysis of 3 revealed that in this reaction instead of the tetramer the monomeric form, ionic complex [Cu{η1‐P(SiMe3)‐PiPr2}2]–[Li(Diglyme)2]+ was formed.  相似文献   

3.
The reaction of CuCl, LiAs(SiMe3)2 and dppb (Bis(diphenylphosphino)butane) leads to the formation of ionic cluster complexes. Depending on the reaction conditions one can isolate [Cu8As3(AsSiMe3)2(dppb)4]+[Cu{As2(SiMe3)2}{As4(SiMe3)4}]‐ ( 1 ) and [Cu8As3(AsSiMe3)2(dppb)4]+[Cu{As(SiMe3)2}2]‐ ( 2 ). The same reaction of CuCl, dppm (Bis(diphenylphosphino)methane) and LiSb(SiMe3)2 leads to the neutral cluster complex [Cu10(Sb3)2(SbSiMe3)2(dppm)6] ( 3 ). The structures of 1‐3 have been solved by X‐ray single crystal analyses.  相似文献   

4.
Synthesis and Crystal Structures of New Phosphorus‐bridged Bimetallic Clusters of the Elements Mercury and Iron The reaction of [Fe(CO)4(HgX)2] (X = Cl, Br) with P(SiMe3)2tBu in the presence of tertiary phosphines and phosphinium salts leads to the ionic compounds [PPh4]2[Hg12{Fe(CO)4}8(PtBu)4X2] (X = Cl, Br) ( 1 , 2 ). If [Fe(CO)4(HgX)2] reacts with P(SiMe3)2tBu the polymeric polynuclear complex [Hg15{Fe(CO)4}3(PtBu)8Br8]n ( 3 ) as well as the twenty mercury‐ and eight iron‐atoms containing [Hg20{Fe(CO)4}8(PtBu)10X4]‐clusters (X = Br, Cl) ( 4 , 5 ) are formed. The reaction of [Fe(CO)4(HgX)2] with LiPPh2 yields to the phosphanido‐bridged [Hg4{Fe(CO)4}2(PPh2)2Cl2] ( 6 ), where as the use of LiP(SiMe3)Ph leads to the diphosphinidene‐bridged cluster [Li(thf)4]2[Hg10{Fe(CO)4}6(P2Ph2)2Br6] ( 7 ). The structures of the compounds 1–7 were characterized by X‐ray single crystal structure analysis.  相似文献   

5.
Syntheses and Crystal Structures of Chalcogenido‐bridged Nickel Cluster Compounds [Ni5Se4Cl2(PPhEt2)6], [Ni12Se12(PnPr3)6], and [Ni18S18(PiPr3)6] The reaction of (R)ESiMe3 (R = SiMe3, Mes = C9H11; E = S, Se) with [NiCl2(PPhEt2)2] and [NiCl2(PR3)2] (R = nPr, iPr) gives new chalcogenido‐bridged nickel cluster compounds [Ni5Se4Cl2(PPhEt2)6]·2THF ( 1 ), [Ni12Se12(PnPr3)6]·2THF ( 2 ), and [Ni18S18(PiPr3)6]·2THF ( 3 ). The structures of these compounds were determined by single crystal X‐ray structural analyses.  相似文献   

6.
We report on the synthesis of new derivatives of silylated clusters of the type [Ge9(SiR3)3]? (R = SiMe3, Me = CH3; R = Ph, Ph = C6H5) as well as on their reactivity towards copper and zinc compounds. The silylated cluster compounds were synthesized by heterogeneous reactions starting from the Zintl phase K4Ge9. Reaction of K[Ge9{Si(SiMe3)3}3] with ZnCl2 leads to the already known dimeric compound [Zn(Ge9{Si(SiMe3)3}3)2] ( 1 ), whereas upon the reaction with [ZnCp*2] the coordination of [ZnCp*]+ to the cluster takes place (Cp*=1,2,3,4,5‐pentamethylcyclopentadienyl) under the formation of [ZnCp*(Ge9{Si(SiMe3)3}3)] ( 2 ). A similar reaction leads to [CuPiPr3(Ge9{Si(SiMe3)3}3)] ( 3 ) from [CuPiPr3Cl] (iPr=isopropyl). Further we investigated the novel silylated cluster units [Ge9(SiPh3)3]? ( 4 ) and [Ge9(SiPh3)2]? ( 5 ), which could be identified by mass spectroscopy. Bis‐ and tris‐silylated species can be synthesized by the respective stoichiometric reactions, and the products were characterized by ESI‐MS and NMR experiments. These clusters show rather different reactivity. The reaction of the tris‐silylated anion 4 with [CuPiPr3Cl] leads to [(CuPiPr3)3Ge9(SiPh3)2]+ as shown from NMR experiments and to [(CuPiPr3)4{Ge9(SiPh3)2}2] ( 6 ), which was characterized by single‐crystal X‐ray diffraction. Compound 6 shows a new type of coordination of the Cu atoms to the silylated Zintl clusters.  相似文献   

7.
Syntheses and Crystal Structures of Novel Chalcogenido‐bridged Niobium Copper Clusters In the presence of tertiary phosphines, the reaction of NbCl5 and Copper(I) salts with Se(SiMe3)2 (E = S, Se) affords the new chalcogenido‐bridged niobium‐copper cluster compounds ( 1 ) and [NbCu4Se4Cl (PPh3)4] ( 2 ). Using E(R)SiMe3 (E = S, Se, R = Ph, nPr) instead of the bisilylated selenium species leads to the compounds [NbCu2(SPh)6(PMe3)2] ( 3 ), [NbCu2(SPh)6(PnPr3)2] ( 4 ), [NbCu2(SePh)6(PMe3)2] ( 5 ), [NbCu2(SePh)6(PnPr3)2] ( 6 ), [NbCu2(SePh)6(PiPr3)2] ( 7 ), [NbCu2(SePh)6(PtBu3)2] ( 8 ), [NbCu2(SePh)6(PiPr2Me)2] ( 9 ), [NbCu2(SePh)6(PPhEt2)2] ( 10 ), [Nb2Cu2(SnPr)8(PnPr3)2Cl2] ( 11 ) and [Nb2Cu6(SnPr)12(PiPr3)2Cl4]·2 CH3CN ( 12 ·2 CH3CN). By reacting CuI salts and NbCl5 with the monosilylated selenides Se(tBu)SiMe3 and Se(iPr)SiMe3 which have a weak Se–C bond the products [Nb2Cu6Se6(PiPr3)6Cl4] ( 13 ), [Nb2Cu4Se2(SeiPr)6(PnPr3)4Cl2] ( 14 ) and [Nb2Cu6Se2(SeiPr)10(PEt2Me)2Cl2]·DME ( 15 ) are formed which contain selenide as well as alkylselenolate ligands. The molecular structures of all of these new compounds were determined by single crystal X‐ray diffraction measurements.  相似文献   

8.
The reaction of iPr2Si(PH2)2 ( 1 ) with [Ca{N(SiMe3)2}2(THF)2] at 25 °C in molar ratio 1:1 yields the compound [Ca3{iPr2Si(PH)2}3(THF)6] ( 2 ). Compound 2 consists of two Ca2P3 trigonal bipyramids with one conjoint calcium corner and SiiPr2 bridged phosphorus atoms. In contrast, the same reaction at 60 °C yield the complex [Ca({P(SiiPr2)2PH}2(THF)4] ( 3 ). The isotype strontium compound [Sr({P(SiiPr2)2PH}2(THF)4] ( 4 ) was obtained from the reaction of iPr2Si(PH2)2 with [Sr{N(SiMe3)2}2(DME)2]. The Compounds 2 – 4 were characterised by single crystal X‐ray diffraction, elemental analysis as well as IR and NMR spectroscopic techniques.  相似文献   

9.
Through SiP bond cleavage, the reaction of P7(SiMe3)3 with one equivalent of KOtBu or LiOtBu afforded different isomers of the heptaphosphanide anion [P7(SiMe3)2]−. With LiOtBu, concomitant inversion at an equatorial (silylated) phosphorus atom occurred and the Cs symmetric isomer characterized by a mirror plane formed. With KOtBu, inversion did not occur and the resulting asymmetric anion with C1 symmetry formed. With NaOtBu, a mixture of both isomers was obtained. The symmetries and structures of the anions were elucidated with 31P{1H} and 29Si{1H} NMR spectroscopy, and relative stabilities were calculated employing the B3LYP/6-31+G* method.The reaction of KP7(SiMe3)2 or LiP7(SiMe3)2 with 1,2-dichlorotetramethyldisilane led to (SiMe3)2P7SiMe2SiMe2P7(SiMe3)2, a molecule composed of two P7-cages connected by a disilane bridge. It can also be obtained through silyl exchange using P7(SiMe3)3 and ClMe2SiSiMe2Cl. The compound was characterized with 31P and 29Si-NMR spectroscopy and elemental analysis. Treatment of P7(SiMe3)3 with HypCl (Hyp = hypersilyl = Si(SiMe3)3) in DME led to the quantitative formation of Hyp2P7SiMe3. Single crystal X-ray diffraction as well as 31P and 29Si-NMR spectroscopy proves the presence of a heteroleptically substituted heptaphosphane cage.Quantum chemical HF and B3LYP/6-31G* calculations of equilibrium structures for the two possible isomers of P7(SiMe3)3 (sym and asym) reveal that asym is destabilized by about 30-40 kJ mol−1, which explains why its formation could not be observed. The phosphorus inversion barrier for the sym → asym transition is calculated as 60-70 kJ mol−1.  相似文献   

10.
Syntheses and Crystal Structures of [Cu4(As4Ph4)2(PRR′2)4], [Cu14(AsPh)6(SCN)2(PEt2Ph)8], [Cu14(AsPh)6Cl2(PRR′2)8], [Cu12(AsPh)6(PPh3)6], [Cu10(AsPh)4Cl2(PMe3)8], [Cu12(AsSiMe3)6(PRR′2)6], and [Cu8(AsSiMe3)4(PtBu3)4] (R, R′ = Organic Groups) Through the reaction of CuSCN with AsPh(SiMe3)2 in the presence of tertiary phosphines the compounds [Cu4(As4Ph4)2(PRR′2)4] ( 1 – 3 ) ( 1 : R = R′ = nPr, 2 : R = R′ = Et; 3 : R = Me, R′ = nPr) and [Cu14(AsPh)6(SCN)2(PEt2Ph)8] ( 4 ) can be synthesised. Using CuCl instead of CuSCN results to the cluster complexes [Cu14(AsPh)6Cl2(PRR′2)8] ( 5–6 ) ( 5 : R = R′ = Et; 6 : R = Me, R′ = nPr), [Cu12(AsPh)6(PPh3)6] ( 7 ) and [Cu10(AsPh)4Cl2(PMe3)8] ( 8 ). Through reactions of CuOAc with As(SiMe3)3 in the presence of tertiary phosphines the compounds [Cu12(AsSiMe3)6(PRR′2)6] ( 9 – 11 ) ( 9 : R = R′ = Et; 10 : R = Ph, R′ = Et; 11 : R = Et, R′ = Ph) and [Cu8(AsSiMe3)4(PtBu3)4] ( 12 ) can be obtained. In each case the products were characterised by single‐crystal‐X‐ray‐structure‐analyses. As the main structure element 1 – 3 each have two As4Ph42–‐chains as ligands. In contrast 4 – 12 contain discrete AsR2–ligands.  相似文献   

11.
New Phosphido-bridged Multinuclear Complexes of Ag and Zn. The Crystal Structures of [Ag3(PPh2)3(PnBu2tBu)3], [Ag4(PPh2)4(PR3)4] (PR3 = PMenPr2, PnPr3), [Ag4(PPh2)4(PEt3)4]n, [Zn4(PPh2)4Cl4(PRR′2)2] (PRR′2 = PMenPr2, PnBu3, PEt2Ph), [Zn4(PhPSiMe3)4Cl4(C4H8O)2] and [Zn4(PtBu2)4Cl4] AgCl reacts with Ph2PSiMe3 in the presence of tertiary Phosphines (PnBu2tBu, PMenPr2, PnPr3 and PEt3) to form the multinuclear complexes [Ag3(PPh2)3(PnBu2tBu)3] 1 , [Ag4(PPh2)4(PR3)4] (PR3 = PMenPr2 2 , PnPr3 3 ) and [Ag4(PPh2)4(PEt3)4]n 4 . In analogy to that ZnCl2 reacts with Ph2PSiMe3 and PRR′2 to form the multinuclear complexes [Zn4(PPh2)4Cl4(PRR′2)2] (PRR′2 = PMenPr2 5 , PnBu3 6 , PEt2Ph 7 ). Further it was possible to obtain the compounds [Zn4(PhPSiMe3)4Cl4(C4H8O)2] 8 and [Zn4(PtBu2)4Cl4] 9 by reaction of ZnCl2 with PhP(SiMe3)2 and tBu2PSiMe3, respectively. The structures were characterized by X-ray single crystal structure analysis. Crystallographic data see “Inhaltsübersicht”.  相似文献   

12.
New Arsinidene-bridged Multinuclear Cluster Complexes of Ag and Au. The Crystal Structures of [Ag14(AsPh)6Cl2(PR3)8], (PR3 = PEt3, PMenPr2, PnPr3), [M4(As4Ph4)2(PR3)4], (M = Ag, PR3 = PEt3, PnPr3; M = Au, PR3 = PnPr3), [Au10(AsPh)4(PhAsSiMe3)2(PnPr3)6] The reaction of AgCl with PhAs(SiMe3)2 in presence of tertiary phosphines (PR3) leads to arsinidene-bridged silver clusters with the composition [Ag14(AsPh)6Cl2(PR3)8], (PR3 = PEt3 1 , PMenPr2 2 , PnPr3 3 ). Further it is possible to obtain the multinuclear complexes [Ag4(As4Ph4)2(PR3)4], (PR3 = PEt3 4 , PMenPr2 5 ). In analogy to that [PMe3AuCl] reacts with PhAs(SiMe3)2 and PnPr3 to form the compound [Au4(As4Ph4)2(PnPr3)4] 6 , which is isostructurell to 4 and 5 . The gold cluster [Au10(AsPh)4(PhAsSiMe3)2(PnPr3)6] 7 was obtained from the same solution. The structures were characterized by X-ray single crystal structure analysis. (Crystallographic data see “Inhaltsübersicht”)  相似文献   

13.
The metalation of HP(SiMe3)2 with Y[CH(SiMe3)2]3 gives the homoleptic {Y[P(SiMe3)2]3}2 (1) which crystallizes from toluene in the monoclinic space group P21/c. The yttrium atoms are in a distorted tetrahedral environment with Y‐P bond lengths of 267.7 and 284.8 pm to the terminal and bridging substituents, respectively. The metathesis reaction of [1, 3‐(Me3Si)2C5H3]2YCl with KPSitBu3 yields (tetrahydrofuran‐O)‐1, 1', 3, 3'‐tetrakis(trimethylsilyl)yttrocene‐tri(tert‐butyl)silylphosphanide ( 2 ). The molecular structure of 2 in solution was deduced by NMR spectroscopy and X‐ray crystallography. The coupling constants 1J(Y, P) and 1J(P, H) show values of 144.0 Hz and 201.0 Hz, respectively.  相似文献   

14.
Coordinatively Unsaturated Iron Chalcogenolate Complexes with Trigonal Planar Ligand Spheres – Synthesis, Properties, and Reactions with Nitrogen and Oxygen Donor Molecules The new bulky organo-selenium compound 2,4,6-triphenylbenzeneselenole ( 1 A ) was synthesized by a multistep-reaction from 1,3,5-triphenylbenzene. 1 A was converted by oxidation into the air-stable bis(2,4,6-triphenylphenyl)diselenide ( 1 B ), which was characterized by X-ray diffraction. The stepwise reaction of [Fe2{N(SiMe3)2}4] with 1 A leads to the complexes [Fe2(SeC6H2-2,4,6-Ph3)2{N(SiMe3)2}2] ( 2 ) and [Fe2(SeC6H2-2,4,6-Ph3)4] ( 3 ), controlled by their molar ratios. The conversion of 2 to 3 is also described. In addition, the coordinatively unsaturated thiolate complexes [Fe2{SC6H3-2,6-(SiMe3)2}2{N(SiMe3)2}2] ( 4 ) and [Fe2{SC6H3-2,6-(SiMe3)2}4] ( 5 ) were synthesized by stepwise reaction of [Fe2{N(SiMe3)2}4] with 2,6-bis(trimethylsilyl)benzenethiole. It is also possible to convert the heteroleptic compound 4 into the homoleptic thiolate complex 5 . During our investigations of the reactivity of 5 towards small electroneutral molecules, the compounds [Fe2{SC6H3-2,6-(SiMe3)2}4 · (MeCN)2] ( 6 ) and [Fe{SC6H3-2,6-(SiMe3)2}2(OPEt3)] ( 7 ) were obtained. 6 is the product of the addition of two molecules of acetonitrile to 5 . The iron atoms of 6 are coordinated by three sulfur and one nitrogen atom in a distorted tetrahedral manner. When 5 is treated with triethylphosphine oxide instead of acetonitrile, the mononuclear complex 7 with the coordination number three is formed. The iron atom is surrounded by two sulfur and one oxygen donor functions.  相似文献   

15.
Zincselenide- and Zinctellurideclusters with Phenylselenolate- and Phenyltellurolateligands. The Crystal Structures of [NEt4]2[Zn4Cl4(SePh)6], [NEt4]2[Zn8Cl4Se(SePh)12], [Zn8Se(SePh)14(PnPr3)2], [HPnPr2R]2[Zn8Cl4Te(TePh)12] (R = nPr, Ph), and [Zn10Te4(TePh)12(PR3)2] (R = nPr, Ph) In the prescence of NEt4Cl ZnCl2 reacts with PhSeSiMe3 or a mixture of PhSeSiMe3/Se(SiMe3)2 to form the ionic complexes [NEt4]2[Zn4Cl4(SePh)6] 1 or [NEt4]2[Zn8Cl4Se(SePh)12] 2 respectively. The use of PnPr3 instead of the quarternary ammonia salt leads in toluene to the formation of crystalline [Zn8Se(SePh)14(PnPr3)2] 3 . Reactions of ZnCl2 with PhTeSiMe3 and tertiary phosphines result in acetone in crystallisation of the ionic clusters [HPnPr2R]2[Zn8Cl4Te(TePh)12] (R = nPr 4 , Ph 5 ) and in THF of the uncharged [Zn10Te4(TePh)12(PR3)2] (R = nPr 6 , Ph 7 ). The structures of 1–7 were obtained by X-ray single crystal structure. ( 1 : space group P21/n (No. 14), Z = 4, a = 1212,4(2) pm, b = 3726,1(8) pm, c = 1379,4(3) pm β = 99,83(3)°; 2 space group P21/c (Nr. 14), Z = 4, a = 3848,6(8) pm, b = 1784,9(4) pm, c = 3432,0(7) pm, β = 97,78(3)°; 3 : space group Pnn2 (No. 34), Z = 2, a = 2027,8(4) pm, b = 2162,3(4) pm, c = 1668,5(3) pm; 4 : space group P21/c (No. 14), Z = 4, a = 1899,8(4) pm, b = 2227,0(5) pm, c = 2939,0(6) pm, β = 101,35(3)°; 5 : space group space group P21/n (No. 14), Z = 4, a = 2231,0(5) pm, b = 1919,9(4) pm, c = 3139,5(6) pm, β = 109,97(4)°; 6 : space group I41/a (No. 88), Z = 4, a = b = 2566,0(4) pm, c = 2130,1(4) pm; 7 : space group P1¯ (No. 2), Z = 2, a = 2068,4(4) pm, b = 2187,8(4) pm, c = 2351,5(5) pm, α = 70,36°, β = 84,62°, γ( = 63,63°)  相似文献   

16.
Treatment of AsP3 with 0.75 equivalents of [{GaC(SiMe3)3}4] resulted in selective insertion of three equivalents of {GaC(SiMe3)3} into the three As? P bonds to give [As{GaC(SiMe3)3}3P3] ( 1 ‐As) with an intact cyclo‐P3 ring. This yellow compound has been characterized by NMR spectroscopy, combustion analysis, single‐crystal X‐ray diffraction, UV/Vis spectroscopy, Raman spectroscopy, and cyclic voltammetry (THF, 0.2 M [TBA][B(C6F5)4]; TBA=tetrabutyl ammonium). Computational models of 1 ‐As and the isomeric [P{GaC(SiMe3)3}3AsP2] ( 1 ‐P) have been investigated as well, revealing several interesting electronic features of these cage molecules. Following from the cyclic voltammetry studies of 1 ‐As that highlight an irreversible two‐electron reduction at ?2.2 V versus Fc/Fc+, treatment with one equivalent of [Mg(C14H10)(thf)3] resulted in two‐electron reduction to provide [As{GaC(SiMe3)3}3P3Mg(thf)3] ( 2 ), in which the Mg2+ ion has inserted into one of the P? P bonds of the cyclo‐P3 ring. It was also found that treatment of AsP3 or P4 with one equivalent of [{GaC(SiMe3)3}4] resulted in formation of the quadruple insertion products [As{GaC(SiMe3)3}4P3] ( 3 ) and [P{GaC(SiMe3)3}4P3] ( 4 ), respectively.  相似文献   

17.
Treatment of Co4(CO)12 with an excess of trimethylsilylacetylene (TMSA) in the presence of tri(2‐thienyl)phosphine in THF at 25 °C for 2 hours yielded six compounds. Two pseudo‐octahedral, alkyne‐bridged tetracobalt clusters, [Co4(μ4‐η2‐HC≡CSiMe3)(CO)10(μ‐CO)2] ( 4 ) and [Co4(μ4‐η2‐HC≡CSiMe3)‐(CO)9(μ‐CO)2{P(C4H4S)3}] ( 6 ), along with an alkyne‐bridged dicobalt complex, [Co2(CO)5(μ‐HC≡CSiMe3)‐{P(C4H4S)3}] ( 5 ), were obtained as new compounds. The addition of the thienylphosphine ligand, in fact, facilitates the reaction rate. Reaction of an alkyne‐bridged dicobalt complex, [(η2‐H‐C≡C‐SiMe3)Co2(CO)6] ( 3 ), with a bi‐functional ligand, PPh(‐C≡C‐SiMe3)2, yielded an unexpected six‐membered, cyclic compound, {(Ph)(Me3Si‐C≡C)P‐[(η2‐C≡C‐SiMe3)Co2(CO)5]}2 ( 7 ). All of these new compounds were characterized by spectroscopic means; the solid‐state structures of ( 5 ), ( 6 ) and ( 7 ) have been established by X‐ray crystallography.  相似文献   

18.
The title compound, poly[potassium [diaquapenta‐μ2‐dicyanamido‐dicadmium(II)] dihydrate], {K[Cd2(C2N3)5(H2O)2]·2H2O}n, contains two‐dimensional anionic sheets of {[Cd2{N(CN)2}(H2O)2]−}n with a modified (6,3)‐net (layer group , No. 35). Two sets of equivalent sheets interpenetrate orthogonally to form a tetragonal enmeshed grid.  相似文献   

19.
The reaction of YbCl3 with two equivalents of NaN‐(SiMe3)2 has afforded a mixture of several ytterbium bis(trimethylsilyl) amides with the known complexes [Yb{N(SiMe3)2}2(μ‐Cl)(thf)]2 ( 1 ) and [Yb{N(SiMe3)2}3]( 4 ) as the main products and the cluster compound [Yb3Cl4O{N(SiMe3)2}3(thf)3]( 2 ) as a minor product. Treatment of 1 and 2 with hot n‐heptane gave the basefree complex [Yb{N(SiMe3)2}2(μ‐Cl)]2 ( 3 ) in small yield. The structures of compounds 1—4 and the related peroxo complex [Yb2{N(SiMe3)2}4(μ‐O2)(thf)2]( 5 ) have been investigated by single crystal X‐ray diffraction. In the solid‐state, 3 shows chlorobridged dimers with terminal amido ligands (av. Yb—Cl = 262.3 pm, av. Yb—N = 214.4 pm). Additional agostic interactions are observed from the ytterbium atoms to four methyl carbon atoms of the bis(trimethylsilyl)amido groups (Yb···C = 284—320 pm). DFT calculations have been performed on suitable model systems ([Yb2(NH2)4(μ‐Cl)2(OMe2)2]( 1m ), [Yb2(NH2)4(μ‐Cl)2]( 3m ), [Yb‐(NH2)3]( 4m ), [Yb2(NH24(μ‐O2)(OMe2)2]( 5m ), [Yb{N‐(SiMe3)2}2Cl] ( 3m/2 ) and Ln(NH2)2NHSiMe3 (Ln = Yb ( 6m ), Y ( 7m )) in order to rationalize the different experimentally observed Yb—N distances, to support the assignment of the O—O stretching vibration (775 cm ‐1) in the Raman spectrum of complex 5 and to examine the nature of the agostic‐type interactions in σ‐donorfree 3 .  相似文献   

20.
Amido Metalates of Rare Earth Elements. Syntheses and Crystal Structures of [Na(12-crown-4)2][M{N(SiMe3)2}3(OSiMe3)] (M = Sm, Yb), [Na(THF)3Sm{N(SiMe3)2}3(C≡C–Ph)], [Na(THF)6][Lu2(μ-NH2)(μ-NSiMe3){N(SiMe3)2}4], and of [NaN(SiMe3)2(THF)]2. Applications of Rare Earth Metal Complexes as Polymerization Catalysts The amido silyloxy complexes [Na(12-crown-4)2][M{N(SiMe3)2}3(OSiMe3)] with M = Sm ( 1 a ), Eu ( 1 b ), Yb ( 1 c ), and Lu ( 1 d ) were obtained from the trisamides M[N(SiMe3)3]3 and NaOSiMe3 in n-hexane in the presence of 12-crown-4; they form yellow to orange-red crystals, of which 1 a and 1 c were characterized crystallographically. The complexes crystallize isotypically with one another in the monoclinic space group I2/a with eight formula units per unit cell. The metal atoms of the complex anions are tetrahedrally coordinated by the three nitrogen atoms of the N(SiMe3)2– ligands and by the oxygen atom of the OSiMe3– ligand. With 172.4° for 1 a and 179.3° for 1 c the bond angles M–O–Si are practically linear. With ethynylbenzene in the presence of NaN(SiMe3)2 in tetrahydrofuran the trisamides M[N(SiMe3)2]3 react under formation of the complexes [Na(THF)3M{N(SiMe3)2}3 · (C≡C–Ph)] with M = Ce ( 2 a ), Sm ( 2 b ), and Eu ( 2 c ), of which 2 b was characterized crystallographically (monoclinic, space group P21/n, Z = 4). 2 b forms an ion pair in which the terminal carbon atom of the C≡C–Ph– ligand is connected with the samarium atom of the Sm[N(SiMe3)2]3 group and the sodium ion is side-on connected with the acetylido group. According to the crystal structure determination (space group P212121, Z = 4) [Na(THF)6][Lu2(μ-NH2)(μ-NSiMe3) · {N(SiMe3)2}4] ( 3 ), which is formed as a by-product, consists of [Na(THF)6]+ ions and dimeric anions, in which the lutetium atoms are connected to form a planar Lu2N2 four-membered ring via a μ-NH2 bridge with average Lu–N distances of 227.2 pm and via a μ-NSiMe3 bridge of average Lu–N distances of 218.5 pm. According to the crystal structure determination (space group P 1, Z = 1) [NaN(SiMe3)2(THF)]2 ( 4 ) forms centrosymmetric dimeric molecules with Na–N distances of the Na2N2 four-membered ring of 239.9 pm and distances Na–O of the terminally bonded THF molecules which are 226.7 pm. The vinylic polymerization of methylmethacrylate (MMA) catalyzed by 1 c resulted in high molecular weight polymethylmethacrylate (PMMA) with moderate yields. The reaction of 1 a or 2 b with MMA did not give PMMA. Insoluble polynorbornene was obtained in low yields by reaction of norbornene/methylaluminoxane (MAO) with 1 a , 1 c , or 2 b . The ring opening polymerization of ϵ-caprolacton or δ-valerolacton catalyzed by 2 b resulted in corresponding polylactones in quantitative yields.  相似文献   

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