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1.
3,4-Bis[pentamethylcyclopentadienyl]tricyclo-[3.1.0.02,6] hexaphosphane 1 reacts with Cr(CO)5thf or W(CO)5thf to give the zwitterionic chromium complex 1,9,10-tris(pentacarbonylchromium)−3,4,5,6,11-pentamethyl-7-pentamethylcyclopentadienyl-3,4,5,6,11-pentacarba-penta-cyclo-[6.1. 1.1,8.13,6.O2,7.010,11 ]-4-en-7-ium-9-id-undeca-phosphane 2 and the analogous tungsten compound 3, respectively. The basic structures of 2 and 3 are similar to the cunean-moiety of the Hittorf-modification of phosphorus.  相似文献   

2.
Unexpected Reduction of [Cp*TaCl4(PH2R)] (R = But, Cy, Ad, Ph, 2,4,6‐Me3C6H2; Cp* = C5Me5) by Reaction with DBU – Molecular Structure of [(DBU)H][Cp*TaCl4] (DBU = 1,8‐diazabicyclo[5.4.0]undec‐7‐ene) [Cp*TaCl4(PH2R)] (R = But, Cy, Ad, Ph, 2,4,6‐Me3C6H2 (Mes); Cp* = C5Me5) react with DBU in an internal redox reaction with formation of [(DBU)H][Cp*TaCl4] ( 1 ) (DBU = 1,8‐diazabicyclo[5.4.0]undec‐7‐ene) and the corresponding diphosphane (P2H2R2) or decomposition products thereof. 1 was characterised spectroscopically and by crystal structure determination. In the solid state, hydrogen bonding between the (DBU)H cation and one chloro ligand of the anion is observed.  相似文献   

3.
Die Reaktion von [Cp′′′Co(η4‐P4)] ( 1 ) (Cp′′′=1,2,4‐tBu3C5H2) mit MeNHC (MeNHC=1,3,4,5‐tetramethylimidazol‐2‐ylidene) führt über eine NHC‐induzierte Phosphorkationen‐Abstraktion zum Ringkontraktionsprodukt [(MeNHC)2P][Cp′′′Co(η3‐P3)] ( 2 ), welches das erste Beispiel eines anionischen CoP3‐Komplexes repräsentiert. Solche von NHCs induzierten Ringkontraktionsreaktionen lassen sich ebenfalls auf Tripeldecker‐Sandwich‐Komplexe anwenden. So werden die Komplexe [(Cp*Mo)2(μ,η6:6‐E6)] ( 3 a , 3 b ) (Cp*=C5Me5; E=P, As) zu den Komplexen [(MeNHC)2E][(Cp*M)2(μ,η3:3‐E3)(μ,η2:2‐E2)] ( 4 a , 4 b ) transformiert, wobei 4 b das erste strukturell charakterisierte Beispiel eines NHC‐substituierten AsI‐Kations darstellt. Darüber hinaus führt die Reaktion des Vanadium‐Komplexes [(Cp*V)2(μ,η6:6‐P6)] ( 5 ) mit MeNHC zur Bildung der neuartigen Komplexe [(MeNHC)2P][(Cp*V)2(μ,η6:6‐P6)] ( 6 ), [(MeNHC)2P][(Cp*V)2(μ,η5:5‐P5)] ( 7 ) bzw. [(Cp*V)2(μ,η3:3‐P3)(μ,η1:1‐P{MeNHC})] ( 8 ).  相似文献   

4.
The reaction of [Cp′′′Co(η4‐P4)] ( 1 ) (Cp′′′=1,2,4‐tBu3C5H2) with MeNHC (MeNHC=1,3,4,5‐tetramethylimidazol‐2‐ylidene) leads through NHC‐induced phosphorus cation abstraction to the ring contraction product [(MeNHC)2P][Cp′′′Co(η3‐P3)] ( 2 ), which represents the first example of an anionic CoP3 complex. Such NHC‐induced ring contraction reactions are also applicable for triple‐decker sandwich complexes. The complexes [(Cp*Mo)2(μ,η6:6‐E6)] ( 3 a , 3 b ) (Cp*=C5Me5; E=P, As) can be transformed to the complexes [(MeNHC)2E][(Cp*M)2(μ,η3:3‐E3)(μ,η2:2‐E2)] ( 4 a , 4 b ), with 4 b representing the first structurally characterized example of an NHC‐substituted AsI cation. Further, the reaction of the vanadium complex [(Cp*V)2(μ,η6:6‐P6)] ( 5 ) with MeNHC results in the formation of the unprecedented complexes [(MeNHC)2P][(Cp*V)2(μ,η6:6‐P6)] ( 6 ), [(MeNHC)2P][(Cp*V)2(μ,η5:5‐P5)] ( 7 ) and [(Cp*V)2(μ,η3:3‐P3)(μ,η1:1‐P{MeNHC})] ( 8 ).  相似文献   

5.
Synthesis and Properties of Pentamethylcyclopentadienylsubstituted PPC and AsPC three-membered Rings Via the reaction of bis-(pentamethylcyclopentadienyl)diphosphene [Cp*P?PCp*, 1 ] and 1-(pentamethylcyclopentadienyl)-2-(2,4,6-tritbutylphenyl)- diphosphene [Cp*P?PMes*, 2 ] with the diazomethanes N2CHR [R = H, Si(CH3)3] the four new diphosphiranes Cp*PPCp*CHSi(CH3)3, 4a , Cp*PPMes*CHSi(CH3)3, 4b , Cp*PPCp*CH2, 5a , Cp*PPMes*CH2, 5b , are obtained. The formation of 4a results via a 2 + 3-cyclo-addition product, which could be proved by nmr spectroscopy. The reaction of As-(pentamenthylcyclopentadienyl)-P-(2,4,6-tritbutylphenyl) arsaphosphene [Cp*As?PMes*, 3 ] with diazomethane leads to 1-(pentamethylcyclopentadienyl)-2-(2,4,6-tritbutylphenyl)-1-arsa-2 -phosphacyclopropane [phospharsiran, Cp*AsPMes*CH2, 6 ]. Analysis of the structures by nmr spectroscopy gives clear evidence for a trans-orientation of the substituents at the El? P bond (El = As, P) in all of the three membered ring systems. For the diphosphirane Cp*PPCp*CH2 ( 5a ) a Cp*-phosphorus bond cleavage by thermolysis cannot be observed. From the reaction of compound 5a with Cr(CO)5thf one obtains 1-(pentacarbonylchrom)-1,2-bis(pentamethylcyclopentadienyl)-1,2- diphosphacyclo-propane, 7 .  相似文献   

6.
The reaction of [Cp*MCl4] (M = Nb, Ta; Cp* = C5Me5) with PH2R in toluene at room temperature gives the primary phosphine complexes [Cp*MCl4(PH2R)] [Cp* = C5Me5; M = Nb: R = But ( 1a ), Ad ( 2a ), Cy ( 3a ), Ph ( 4a ), 2, 4, 6‐Me3C6H2 (Mes) ( 5a ); M = Ta: R = But ( 1b ), Ad ( 2b ), Cy ( 3b ), Ph ( 4b ), Mes ( 5b )] in high yield. 1—5 were characterized spectroscopically (NMR, IR, MS) and by crystal structure determinations. The starting material [Cp*TaCl4] is monomeric in the solid state, as shown by crystal structure determination.  相似文献   

7.
A route to directly access mixed Al–Fe polyphosphide complexes was developed. The reactivity of pentaphosphaferrocene, [Cp*Fe(η5‐P5)] (Cp*=C5Me5), with two different low‐valent aluminum compounds was investigated. The steric and electronic environment around the [AlI] centre are found to be crucial for the formation of the resulting Al–Fe polyphosphides. Reaction with the sterically demanding [Dipp‐BDIAlI] (Dipp‐BDI={[2,6‐iPr2C6H3NCMe]2CH}?) resulted in the first Al‐based neutral triple‐decker type polyphosphide complex. For [(Cp*AlI)4], an unprecedented regioselective insertion of three [Cp*AlIII]2+ moieties into two adjacent P?P bonds of the cyclo‐P5 ring of [Cp*Fe(η5‐P5)] was observed. The regioselectivity of the insertion reaction could be rationalized by isolating an analogue of the reaction intermediate stabilized by a strong σ‐donor carbene.  相似文献   

8.
Formal [2 + 2 + 2] addition reactions of [Cp*Ru(H2O)(NBD)]BF4 (NBD = norbornadiene) with PhC?CR (R = H, COOEt) give [Cp*Ru(η6‐C6H5? C9H8R)] BF4 (1a, R = H; 2a, R = COOEt). Treatment of [Cp*Ru(H2O)(NBD)]BF4 with PhC?C? C?CPh does not give [2 + 2 + 2] addition product, but [Cp*Ru(η6‐C6H5? C?C? C?CPh)] BF4(3a). Treatment of 1a, 2a, 3a with NaBPh4 affords [Cp*Ru(η6‐C6H5? C9H8R)] BPh4 (1b, R = H; 2b, R = COOEt) and [Cp*Ru(η6‐C6H5? C?C? C?CPh)] BPh4(3b). The structures of 1b, 2b and 3b were determined by X‐ray crystallography. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

9.
Molecular and Crystal Structure of Bis[chloro(μ‐phenylimido)(η5‐pentamethylcyclopentadienyl)tantalum(IV)](Ta–Ta), [{TaCl(μ‐NPh)Cp*}2] Despite the steric hindrance of the central atom in [TaCl2(NPh)Cp*] (Ph = C6H5, Cp* = η5‐C5(CH3)5), caused by the Cp* ligand, the imido‐ligand takes a change in bond structure when this educt is reduced to the binuclear complex [{TaCl(μ‐NPh)Cp*}2] in which tantalum is stabilized in the unusual oxidation state +4.  相似文献   

10.
Unprecedented functionalized products with an η4‐P5 ring are obtained by the reaction of [Cp*Fe(η5‐P5)] ( 1 ; Cp*=η5‐C5Me5) with different nucleophiles. With LiCH2SiMe3 and LiNMe2, the monoanionic products [Cp*Fe(η4‐P5CH2SiMe3)]? and [Cp*Fe(η4‐P5NMe2)]?, respectively, are formed. The reaction of 1 with NaNH2 leads to the formation of the trianionic compound [{Cp*Fe(η4‐P5)}2N]3?, whereas the reaction with LiPH2 yields [Cp*Fe(η4‐P5PH2)]? as the main product, with {[Cp*Fe(η4‐P5)]2PH}2? as a byproduct. The calculated energy profile of the reactions provides a rationale for the formation of the different products.  相似文献   

11.
Double chloride abstraction of Cp*AsCl2 gives the dicationic arsenic species [(η5‐Cp*)As(tol)][B(C6F5)4]2 ( 2 ) (tol=toluene). This species is shown to exhibit Lewis super acidity by the Gutmann–Beckett test and by fluoride abstraction from [NBu4][SbF6]. Species 2 participates in the FLP activation of THF affording [(η2‐Cp*)AsO(CH2)4(THF)][B(C6F5)4]2 ( 5 ). The reaction of 2 with PMe3 or dppe generates [(Me3P)2As][B(C6F5)4] ( 6 ) and [(σ‐Cp*)PMe3][B(C6F5)4] ( 7 ), or [(dppe)As][B(C6F5)4] ( 8 ) and [(dppe)(σ‐Cp*)2][B(C6F5)4]2 ( 9 ), respectively, through a facile cleavage of C?As bonds, thus showcasing unusual reactivity of this unique As‐containing compound.  相似文献   

12.
New 1,1′-Ferrocene Dichalcogenato Complexes of Ruthenium and Osmium Both trinuclear 1,1′-ferrocene dichalcogenato complexes(1) such as fc(E[MLn])2 ( 1a—c ) (with [MLn] = Ru(CO)2Cp*; E = S, Se, Te) and dinuclear [3]ferrocenophane derivatives of the type fcE2[MLn] (with [MLn] = Ru(CO)(η6-C6Me6) ( 2a, b ), Ru(NO)Cp* ( 3a, b ) (E = S, Se) or Os(NO)Cp* ( 4a—c ) (E = S, Se, Te)) were synthesized and characterized by their IR-, 1H- and 13C NMR spectra as well as their mass spectra. The molecular structure of fcS2[Os(NO)Cp*] ( 4a ) was determined by an X-Ray structure analysis; the long Fe…?Os distance of 431.1(1)pm excludes any direct bonding interactions.  相似文献   

13.
[CpR(OC)Mo(μ‐η2:2‐P2)2FeCpR′] as Educt for Heterobimetallic Dinuclear Clusters with P2 and CnRnP4‐n Ligands (n = 1, 2) The cothermolysis of [CpR(OC)Mo(μ‐η2:2‐P2)2FeCpR′] ( 1 ) and tBuC≡P ( 2 ) as well as PhC≡CPh ( 3 ) affords the heterobimetallic triple‐decker like dinuclear clusters [(Cp'''Mo)(Cp*′Fe)(P3CtBu)(P2)] ( 4 ), Cp''' = C5H2tBu3‐1,2,4, Cp*′ = C5Me4Et, and [(Cp*Mo)(Cp*Fe)(P2C2Ph2)(P2)] ( 5 ) with a bridging tri‐ and diphosphabutadiendiyl ligand. 4 and 5 have been characterized additionally by X‐ray crystallography.  相似文献   

14.
The first title metallocene, 1,3‐bis(dichlorotitanocene)‐1,1,3,3‐tetramethyldisiloxane dichloromethane solvate, [(η5‐C5H5)­TiCl2­(η5‐C5H4­Si­Me2)]2O·­CH2Cl2, (I), crystallizes in space group P21/c. Compound (I) represents the first crystal structure of a bimetallic siloxy‐bridged titanocene. The geometric parameters of (I) are similar to those of the parent titanocene; however, the disiloxane substituents adopt an unexpected eclipsed conformation. The second title metallocene, 1,3‐bis­[(penta­methyl­cyclo­penta­dienyl)­(cyclo­penta­dien­yl)­titanium dichloride]‐1,1,3,3‐tetra­methyl­disiloxane, [(η5‐C5‐Me5)­TiCl2­(η5‐C5H4­Si­Me2)]2O, (II), represents the second crystal structure of a bimetallic siloxy‐bridged titanocene and crystallizes in the space group P21/n. Compound (I) possesses non‐crystallographic twofold molecular symmetry and both metal centers adopt pseudo‐tetrahedral geometries. The geometric parameters of (II) are similar to those of the mixed titanocene Cp*CpTiCl2 (Cp* = C5Me5) and the disiloxane substituents adopt a staggered conformation.  相似文献   

15.
Reaction of [CpnMCl4?x] (M=V: n=x=2; M=Nb: n=1, x=0) or [Cp*TaCl4] (Cp=η5‐C5H5, Cp*=η5‐C5Me5), with [LiBH4?thf] at ?70 °C followed by thermolysis at 85 °C in the presence of [BH3?thf] yielded the hydrogen‐rich metallaboranes [(CpM)2(B2H6)2] ( 1 : M=V; 2 : M = Nb) and [(Cp*Ta)2(B2H6)2] ( 3 ) in modest to high yields. Complexes 1 and 3 are the first structurally characterized compounds with a metal–metal bond bridged by two hexahydroborate (B2H6) groups forming a symmetrical complex. Addition of [BH3?thf] to 3 results in formation of a metallaborane [(Cp*Ta)2B4H8(μ‐BH4)] ( 4 ) containing a tetrahydroborate ligand, [BH4]?, bound exo to the bicapped tetrahedral cage [(Cp*Ta)2B4H8] by two Ta‐H‐B bridge bonds. The interesting structural feature of 4 is the coordination of the bridging tetrahydroborate group, which has two B? H bonds coordinated to the tantalum atoms. All these new metallaboranes have been characterized by mass, 1H, 11B, and 13C NMR spectroscopy and elemental analysis and the structural types were established unequivocally by crystallographic analysis of 1 – 4 .  相似文献   

16.
Contributions to the Chemistry of Phosphorus. 227. HP4º as a Complex Ligand: Formation and Properties of [(η5-C5H5)2ZrCl(P4H)], [(η5-C5Me5)2ZrCl(P4H)], and [(η5-C5H5)3Zr(P4H)] The novel complexes [(η5-C5H5)2ZrCl(P4H)] ( 1 ), [(η5-C5Me5)2ZrCl(P4H)] ( 2 ), and [(η5-C5H5)3Zr(P4H)] ( 3 ) have been obtained by reaction of a solution of (Na/K)HP4 with the zirconocen derivatives [(η5-C5H5)2ZrCl2], [(η5-C5Me5)2ZrCl2], and [(η5-C5H5)31-C5 H5)Zr] under suitable conditions. The structure of the compounds 1 – 3 , which are only stable in solution, has been elucidated by means of 31P-NMR spectroscopy. It is highly probable that the exo,endo isomer exists in each case. In addition, further isomers of lower relative abundancies have been observed, in which the ligands presumably exhibit a different spatial orientation relatively to each other.  相似文献   

17.
Triangulated Dodecahedral Heterotrimetallic‐ and ‐tetrametallic Iron–Ruthenium Clusters with CpR and Pn Ligands (n = 5, 4) The cothermolysis of [Cp*Fe(η5‐P5)] ( 1 ) and [{Cp″(OC)2Ru}2](Ru–Ru) ( 2 ), Cp″ = C5H3But2‐1,3, affords low yields of [Cp″Ru(η5‐P5)] ( 3 ) and [{Cp″Ru}2P4] ( 4 ) as well as the triangulated dodecahedral hetero‐ and homotrimetallic clusters [{Cp″Ru}2{Cp*Fe}P5] ( 5 ), [{Cp″Ru}3P5] ( 6 ), [{Cp*Fe}2{Cp″Ru}P5] ( 7 ) and the tetranuclear compound [{Cp″Ru}3{Cp*Fe}P4] ( 8 ). X‐ray crystallographic studies show that the P5 ligand in the distorted M2M′P5‐triangulated dodecahedra of 5 and 7 offers an unusual novel coordination mode derived from the educt 1 .  相似文献   

18.
When activated with fluorinated borate cocatalysts the trimetallic complexes [Cp*LnMe2]3 (Ln=Y, Lu; Cp*=C5Me5) promote efficiently the formation of high-cis polybutadiene. Respective polyisoprenes instead bear much less pronounced microstructures, but reveal crosslinked products at lower polymerization temperatures. Varying the amount of cocatalyst, the emerging active species were examined by NMR spectroscopic techniques (incl. 1H DOSY). The occurrence of donor-solvent and thermally induced degradation products of the highly reactive precatalyst [Cp*YMe2]3 and derived catalyst species was revealed by the elucidation of methylidene clusters [Cp*3Y3Me4(CH2)(thf)2] and [Cp*6Y6Me4(CH2)4], as well as [(Cp*Y)2Me2(N(Me)2(C6H4)]n[B(C6F5)4]n, implying a multimetallic active species.  相似文献   

19.
A coordinatively unsaturated iron‐methyl complex having an N‐heterocyclic carbene ligand, [Cp*Fe(LMe)Me] ( 1 ; Cp*=η5‐C5Me5, LMe=1,3,4,5‐tetramethyl‐imidazol‐2‐ylidene), is synthesized from the reaction of [Cp*Fe(TMEDA)Cl] (TMEDA=N,N,N′,N′‐tetramethylethylenediamine) with methyllithium and LMe. Complex 1 is found to activate the C? H bonds of furan, thiophene, and benzene, giving rise to aryl complexes, [Cp*Fe(LMe)(aryl)] (aryl=2‐furyl ( 2 ), 2‐thienyl ( 3 ), phenyl ( 4 )). The C? H bond cleavage reactions are applied to the dehydrogenative coupling of furans or thiophenes with pinacolborane (HBpin) in the presence of tert‐butylethylene and a catalytic amount of 1 (10 mol % to HBpin). The borylation of the furan/thiophene or 2‐substituted furans/thiophenes occurs exclusively at the 2‐ or 5‐positions, respectively, whereas that of 3‐substituted furans/thiophenes takes place mainly at the 5‐position and gives a mixture of regioisomers. Treatment of 2 with 2 equiv of HBpin results in the quantitative formation of 2‐boryl‐furan and the borohydride complex [Cp*Fe(LMe)(H2Bpin)] ( 5 ). Heating a solution of 5 in the presence of tert‐butylethylene led to the formation of an alkyl complex [Cp*Fe(LMe)CH2CH2tBu] ( 6 ), which was found to cleave the C? H bond of furan to produce 2 . On the basis of these results, a possible catalytic cycle is proposed.  相似文献   

20.
The reaction of [Cp*2RuBr]+Br with bromine in CH2Cl2 (CD2Cl2) in an inert atmosphere at room temperature produces the complexes [Cp*Ru(Br)C5Me4CH2Br]+Br3 (syn conformer), [Cp*Ru(Br)C5Me3(CH2Br)2]+ (syn and anti conformers), and [Ru(Br)(C5Me4CH2Br)2]+ (syn conformer). All complexes were characterized by 1H and 13C NMR spectroscopy; the former complex, by elemental analysis. These complexes were also prepared by the reaction of [Cp*RuC5Me4CH2]+BF4 with bromine in CH2Cl2. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2712–2718, December, 2005.  相似文献   

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