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1.
The upper limit of the free energy of the barrier to rotation of the platinum bis-phosphine unit in [3,3-(PMe2Ph)2-closo-3,1,2-PtC2B9H11] 1 is 30< kJ mol−1 in dichloromethane solution. This relatively low value is similar in magnitude to crystal-packing forces, and compound 1 crystallises from CH2Cl2-hexane solution as a 1 : 1 mixture of two different conformers with significantly different platinum-to-C2B3 bonding. These observations lead to the proposal of a general mechanism for the mutual rotation of {M(PR3)2} units above C2B9H11.  相似文献   

2.
Posters     
Abstract.

The reaction of thionyl chloride with liquid ammonia produces the thionyl imide anion, NSO? Addition of metal chloride bis-phosphine complexes such as [PtCl2(PMe3)2] the resulting NH3(I) solution has been shown to produce compounds of the type [Pt(NSO)2(PMe3)2].[1] Here, we describe the synthesis of Hg(NSO)2 in liquid ammonia, using HgCl2 as the starting material.  相似文献   

3.
The process and mechanism of the ligand volume controlled Pd(PR3)2 (PR3=PH3, PMe3, and PtBu3) oxidative addition with aryl bromide were investigated, using density functional theory method with the conductor-like screening model. Association pathway and dissocia-tion pathway were investigated by the comparison of several energies. The cleavage energy of Pd(PR3)2 complex was calculated, as well as the oxidative addition reaction barrier energy of Pd(PR3)n (n=1,2) with aryl bromide in N,N-dimethylformamide solvent. This study proved that the ligands volume possessed a great impact on the mechanism of oxidative addition: less bulky ligand palladium associated with aryl bromide via two donor ligands,but larger bulky ligand palladium coordinated via monoligand.  相似文献   

4.
Summary Upon u.v. irradiation of [Fe(CO)4(PR 3 )] with HSiR3 (HSiR3 = HSiMePh2, PR3 = PPh3; HSiR3 = HSiMe2Cl, PR3 = PPh3 or PMe2Ph; HSiR3 = HSiMeCl2, PR3 = PPh3, PMePh2, PMe2Ph or PMe3; HSiR3 = HSiCl3, PR3 = PPh3, PMePh2, PMe2Ph, PMe3 or PBu 3 n ) the corresponding hydridosilyl complexes [Fe(CO)3H(PR3)SiR3] are formed. The complexes have themer configuration with acis disposition of the hydride and the silyl ligands. Prolonged irradiation with an excess of silane results in the formation of bis-silyl complexes [Fe(CO)3(PR3)(SiR3)2], if electron density at the metal is not too high. Thus, [Fe(CO)3H(PPh3)SiMePh2] and [Fe(CO)3-H(PMe2Ph)SiMe2Cl] can be obtained but not the corresponding bis-silyl complexes. Most bis-silyl complexes are obtained asmer-isomers with acis-arrangement of the silyl ligands. Only for [Fe(CO)3(PR3)(SiCl3)2] with small phosphine ligands (PR3 = PMe3 or PMe2Ph) is thefac-isomer formed.Part VII of this series, ref. (1).  相似文献   

5.
C5H5Co(PMe3)2 (I) reacts with CSSe to give C5H5Co(η2-CSSe)PMe3 (IV) and C5H5Co(CS)PMe3 (V). The thiocarbonyl complex V is formed in an almost quantitative yield by Se abstraction from IV and PPh3. The corresponding compounds C5H5Co(CS)PMe2Ph (VII) and C5H5Co(CS)[P(OMe)3] (VIII) are obtained as the main products directly from CSSe and C5H5Co(PMe2Ph)2 or C5H5Co[P(OMe)3]2. In the reaction of C5H5Co(PR3)2 (PR3 = PMe3, PMe2Ph) with CSe2, the carbon diselenide complexes C5H5Co(η2-CSe2)PMe3 (XI) and C5H5Co(η2-CSe2)PMe2Ph (XIV) are formed. XI reacts with PPh3 to give C5H5Co(CSe)PMe3 (XII). Cyclopentadienylcobalt compounds containing CSSe22?, CSe32? and C2Se42? as ligands are isolated as side products in the; reactions of C5H5Co(PR3)2 and C5H5Co(CO)PR3 (PR3 = PMe3, PMe2Ph) with CSSe and CSe2, respectively. Displacement of ethylene from C5H5Rh(C2H4)PMe3 by CSSe yields the complex C5H5Rh(η2-CSSe)PMe3 (XVIII) which reacts with PPh3 to give C5H5Rh(CS)PMe3 (XIX) and with excess CSSe to give C5H5RhC2S2Se2(PMe3) (XX). Besides small amounts of C5H5Rh(η2CSSe)PMe2Ph (XXI), the corresponding metallaheterocycle C5H5RhC2S2Se2(PMe2Ph) (XXII) is formed as the main product from C5H5Rh(C2H4)PMe2Ph and CSSe.  相似文献   

6.
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   

7.
Direct reduction of WCl6 with PMe3 in toluene at 120°C in a sealed tube affords the complexes [WCl4(PMe3)x] (x = 2, 3). [WCl4(PMe3)3] abstracts oxygen from equimolar amounts of water in wet acetone or tetrahydrofuran to give [WOCl2(PMe3)3] in very high yields. This procedure has been successfully applied to the high yield synthesis of other known oxotungsten(IV) complexes, [WOCl2(PR3)3] (PR3 = PMe2Ph and PMePh2). Metathesis reactions of [WOCl2(PMe3)3] with NaX give [WOX2(PMe3)3] (X = NCO, NCS) and [WOX2(PMe3)] (X = Me2NCS2). The synthesis of the trimethylphosphite analogue, [WOCl2(P(OMe)3)3], is also described and the structures of the new complexes assigned on the basis of IR and 1H and 31P NMR spectroscopy.  相似文献   

8.
The reaction of [Pt2X2(-Cl)2(PR3)2] with NaSpy or NaSepy gave complexes of the type [PtX(Epy)(PR3)]n (X=Cl or Ar; E=S or Se; PR3=PEt3, PMe2Ph, PMePh2 or PPh3; n=1 or 2) which were characterized by elemental analysis and by 1H, 31P{1H}, 195Pt{1H} n.m.r. spectroscopy. When X=Cl a dynamic equilibrium between [Pt2Cl2(-Spy)2(PR3)2] and [PtCl(k-S,N-Spy)(PR3)] species exists in CHCl3 solution. The aryl derivatives, X=Ar, exist exclusively as dimers (n=2) with predominantly SN bridging. The [Pt(Spy)2 (PPh3)2] complex, prepared by reacting [PtCl2 (PPh3)2] with NaSpy, dissociates in CHCl3 to [Pt(k-S,N-Spy) (Spy)(PPh3)] and PPh3 at room temperature.  相似文献   

9.
The 1H and 31P NMR spectra of (η3-allyl)Pt(PR3)Cl] (PR3 = PMe3, PCy3, P-t-Bu3, P-n-Bu3, PPh3, PPh2Me, PPhMe2 and P(p-Tol)3) complexes in chloroform have been studied. The results suggest that there is bonding interaction between the phosphine and the allyl group via central metal atom.  相似文献   

10.
On the Reactivity of Alkylthio Bridged 44 CVE Triangular Platinum Clusters: Reactions with Bidentate Phosphine Ligands The 44 cve (cluster valence electrons) triangular platinum clusters [{Pt(PR3)}3(μ‐SMe)3]Cl (PR3 = PPh3, 2a ; P(4‐FC6H4)3, 2b ; P(n‐Bu)3, 2c ) were found to react with PPh2CH2PPh2 (dppm) in a degradation reaction yielding dinuclear platinum(I) complexes [{Pt(PR3)}2(μ‐SMe)(μ‐dppm)]Cl (PR3 = PPh3, 3a ; P(4‐FC6H4)3, 3b ; P(n‐Bu)3; 3e ) and the platinum(II) complex [Pt(SMe)2(dppm)] ( 4 ), whereas the addition of PPh2CH2CH2PPh2 (dppe) to cluster 2a afforded a mixture of degradation products, among others the complexes [Pt(dppe)2] and [Pt(dppe)2]Cl2. On the other hand, the treatment of cluster 2a with PPh2CH2CH2CH2PPh2 (dppp) ended up in the formation of the cationic complex [{Pt(dppp)}2(μ‐SMe)2]Cl2 ( 5 ). Furthermore, the terminal PPh3 ligands in complex 3a proved to be subject to substitution by the stronger donating monodentate phosphine ligands PMePh2 and PMe2Ph yielding the analogous complexes [{Pt(PR3)}2(μ‐SMe)(μ‐dppm)]Cl (PR3 = PMePh2, 3c ; PMe2Ph, 3d ). NMR investigations on complexes 3 showed an inverse correlation of Tolmans electronic parameter ν with the coupling constants 1J(Pt,P) and 1J(Pt,Pt). All compounds were fully characterized by means of NMR and IR spectroscopy. X‐ray diffraction analyses were performed for the complexes [{Pt{P(4‐FC6H4)3}}2(μ‐SMe)(μ‐dppm)]Cl ( 3b ), [Pt(SMe)2(dppm)] ( 4 ), and [{Pt(dppp)}2(μ‐SMe)2]Cl2 ( 5 ).  相似文献   

11.
Mono-cyclopentadienyl complexes CpVX2(PR3)2 and Cp′VX2 (PR3)2 (Cp = η5- C5H5; Cp′ = η5-C5H4Me; R = Me, Et; X = Cl, Br) have been prepared by reaction of VX3(PR3)2 with CpM (M = Na, T1, SnBun3, 1/2 Mg) or Cp′Na. Attempts to prepare analogous complexes with other phosphine ligands, PPh3, PPh2 Me, PPhMe2, Pcy3, DMPE and DPPE failed. Reduction of CpVCl2(PEt3)2 with zinc or aluminium under CO (1 bar) offers a simple method for the preparation of CpV(CO)3(PEt3). The crystal structure of the trimethylphosphine complex CpVCl2(PMe3)2 is reported.  相似文献   

12.
Ammonolysis of Halogeno Complexes of Tetravalent Platinum Reactions of liquid ammonia and ammonium hexahalogenoplatinates(IV) at ?40°C yield mixtures of halogenoammine complexes [Pt(NH3)6?nXn]X4?n (X = Cl, Br, I; n = 3, 2, 1, 0). Hexaammine platinum(IV) salts, [Pt(NH3)6]X4, may be isolated as main product only after several weeks of reaction. Interactions at room temperature of liquid ammonia and hexachloro or hexabromo complexes produce quantitatively the novel dinuclear di-m?-amido-bis[tetraammineplatinum(IV)] complex, [(H3N)4Pt(NH2)2Pt(NH3)4]X6. By interaction of gaseous or liquid ammonia and subsequent addition of potassium amide solution in excess potassium hexaamido platinate(IV), K2[Pt(NH2)6], is formed in good yield.  相似文献   

13.
Binuclear platinum complexes of general formula [Pt2Cl2(-L)(-pz)(PR3)2] [L = 2-Spy, py = pyridyl, S2P(OR)2 (R = Et or i-Pr); pz = pyrazolate; PR3 = PEt3, PMe2Ph or PMePh2] have been synthesized. They adopt a cis configuration in which the phosphine ligands are trans to the single atom bridging ligand, L.  相似文献   

14.
Five complexes of type cis-[PtCl2(PR3)Q] (PR3 =PMe3, PMe2Ph, PEt3; Q = CH2 CHOCOCH3 or CH2=CHCH2OCOCH3) have been prepared. The crystal structure of cis-[PtCl2[PME2Ph)(CH2=CHOCOCH3)] is described. Crystals of cis-[PtCl2(PME2Ph)(CH2-CHOCOCH3)] are triclinic, with a 8.441(4), b 13.660(5), c 7.697(3) Å, a 101.61(3)°, β 111.85(3)° γ 95.22(3)°, pP1, Z = 2. The structure was determined from 2011 reflections I σ 3σ (I) and refined to R = 0.037. The CH3COO grouping is syn to the cis-PMe2Ph ligand, with bond lengths of PtCl (trans to P) 2.367(3), PtCl (trans to olefin) 2.314(3), PtP 2.264(2), and PtC of 2.147(12) and 2.168(11) Å. The complexes cis-[PtCl2- (PR3)Q] were studied by variable temperature 1H and 31P NMR spectroscopy. Spectra of the vinyl acetate complexes were temperature dependent as a result of rotation about the platinum—olefin bond. The rotation was “frozen out” at ca. 240 K; for cis-[PtCl2(PME2Ph)(CH2=CHOCOCH3] ΔG≠ (rotation) 15.0 ± 0.2 kcal mol-1. NMR parameters for the rotamers are reported. NMR studies of the interaction between chloro-bridged complexes of type [Pt2Cl2(PR3)2] (PR3 = P-N-Pr3 or PMe2Ph) and vinyl acetate shows that even at low temperatures (213 K) equilibrium favours the bridged complex and the proportion of trans-[PtCl2(PR3)CH2=CHOCOCH3)] is very small e.g. 2%. The allyl acetate complexes cis-[PtCl2(PR3)(CH2=CHCH2OCOCH3)] showed only one rotamer over the range 333–213 K. Reversible dissociation of cis-[PtCl2(PMe2Ph)- (CH2=CHCH2OCOCH3)] to [Pt2Cl4(PMe2Ph)2] + allyl acetate was studied at ambient temperature. At low temperatures e.g. 213–190 K addition of allyl acetate to a CDCl3 solution of [Pt2Cl2(P-n-Pr3)2] reversibly gave some olefin complex trans-[PtCl2(P-n-Pr3)(CH2=CHCH2OCOCH3)] and some O-bonded complex trans-[PtCl2(P-n-Pr3)(CH2=CHCH2OCOCH3)].  相似文献   

15.
The cyclopentadienylcobalt(I) compounds C5H5Co(PMe3)P(OR)3 (R = Me, Et, Pri) and C5H5Co(C2H4)L (L = PMe3, P(OMe)3, CO) are prepared by ligand substitution starting from C5H5Co(PMe3)2 and C5H5Co(C2H4)2. Whereas the reaction of C5H5Co(PMe3)P(OMe)3 with CH2Br2 mainly gives [C5H5CoBr(PMe3)P(OMe)3]Br, the dihalogenocobalt(III) complexes C5H5CoX2(PMe3) (X = Br, I) are obtained from C5H5Co(CO)PMe3 and CH2X2. Treatment of C5H5Co(CO)PMe3 or C5H5Co(C2H4)PMe3 with CH2ClI at low temperatures produces a mixture of C5H5CoCH2Cl(PMe3)I and C5H5CoCl(PMe3)I, which can be separated due to their different solubilities. The same reaction in the presence of ligand L gives the carbenoidcobalt(III) compounds [C5H5CoCH2Cl(PMe3)L]PF6 in nearly quantitative yields. If NEt3 is used as the Lewis base, the ylide complexes [C5H5Co(CH2PMe3)(PMe3)X]PF6 (X = Br, I) are obtained. The PF6 salts of the dications [C5H5Co(CH2PMe3)(PMe3)L]2+ (L = PMe3, P(OMe)3, CNMe) and [C5H5Co(CH2PMe3)(P(OMe)3)2]2+ are prepared either from [C5H5Co(CH2PMe3)(PMe3)X]+ and L, or more directly from C5H5Co(CO)PMe3, CH2X2 and PMe3 or P(OMe)3, respectively. The synthesis of C5H5CoCH2OMe(PMe3)I is also described.  相似文献   

16.
Abstract

A series of complexes having the general formula, [Co(CNR)3(PR3)2]X2, X = ClO4, BF4 with CNR = CNCMe3, CNCHMe2, CNC6H11. CNCH2Ph and PR3 = PPh3, P(C6H4Me-p)3, P(C6H4OMe-p)3 has been synthesized and characterized. Synthesis can be achieved by reaction of [Co(CNR)4(AsPh3)2]X2 complexes with controlled excess of PR3 ligands, and by AgClO4/AgBF4 oxidation of the [Co(CNR)3(PR3)2]X complexes. The latter procedure is preferable. Alternate syntheses of the [Co(CNR)3(PR3)2]X complexes have also been employed. Five-coordinate Co(II) complexes have not been obtained using CNCMe3 with P(C6H4Me-p)3 ligands, CNCH2Ph with P(C6H4OMe-p)3 ligands, or CNC4H9-n with PPh3 ligands. [Co(CNC-Me3)3{P(C6H4Cl-p)3}2]ClO4 produced only [Co{CNCMe3)4H2O](ClO4)2 upon forced oxidation with excess AgClO4. [Co(CNR)3(PR3)2]X2 complexes appear to undergo varying degrees of distortion from regular (i.e., D 3h symmetry) axially-disubstituted trigonal bipyramidal coordination in the solid state, as evidenced by v(-N°C) IR patterns, but to assume regular trigonal bipyramidal coordination in solution. Effective magnetic moments indicate one-electron paramagnetism, and solution electronic spectra are compatible with trigonal bipyramidal coordination.  相似文献   

17.
The complexes C5H5Rh(PMe3)CS2(II) and C5H5Rh(PMe2Ph)CS2(III) are formed in excellent yields in the reaction of C5H5Rh(C2H4)PR3(PR3 = PMe3, PMe2Ph) with CS2 in benzene. The CS2 ligand in II and III is dihapto-bonded and at least in III is rigid. II reacts with Cr(CO)5THF and C5H5Mn(CO)2THF to give the binuclear complexes C5H5(PMe3)Rh(SCS)Cr(CO)5 (IV) and C5H5- (PMe3)Rh(SCS)Mn(CO)2C5H5 (V) in which the CS2 molecule bridges two different metal atoms. In the reaction of C5H5Rh(C2H4)PMe3 and CS2 under certain conditions a second product of C5H5Rh(PMe3)C2S4 (VI) is formed. The cyrstal structure shows that in this complex a five-membered RhSCSC heterocyclic ring is present.  相似文献   

18.
The hydrogenation of ketones with Co2(CO)6(PR3)2 (PR3 = PPh2-neomenthyl, PPh2 -6-deoxo-1,2:3,4-diisopropylidene d-galactose and PMe2 -menthyl) as catalysts gives optically active alcohols in optical yields of 1.6 to 5%.  相似文献   

19.
The complexes C5H5Rh(PMe3)C2H3R′ (R′  H, Me, Ph) and C5H5Rh(PR3)C2H4(PR3  PMe2Ph, PPri3) are prepared by reaction of[PMe3(C2H3R/t')RhCl]2 or [PR3(C2H4)RhCl]2 and TlC5H5, respectively. They react with HBF4 in ether/propionic anhydride to form the BF4 salts of the hydrido(olefin)rhodium cations [C5H5RhH(C2H3R′)PR3]+(R  Me; R′  H, Me and R  Pri; R′  H). From C5H5Rh(PMe3)C2H3Ph and CF3COOH/NH4PF6 the η3-benzyl complex [C5H5Rh(PMe3)(η3-CH3CHC6H5)]PF6 is obtained. The reversibility of the protonation reactions is demonstrated by temperature-dependent NMR spectra and by deuteration experiments. The complexes C5H5Rh(PMe3)C2H3R′ (R′  H, Ph) and C5H5Rh(PMe2Ph)C2H4 react with CH3I in ether to give the salts [C5H5RhCH3(C2H3R′)PR3]I which in THF or CH3NO2 yield the neutral compounds C5H5RhCH3(PR3)I.  相似文献   

20.
The trihydrides (η5-C5Me5RuH3(PR3 = PMe3, FEt3, Pipr3, PCy3, PPh2Me, and PPh3) (2) are formed in the reaction of paramagnetic (η5C5Me5)RuCl2(PR3) (1) with NaBH4 in ethanol. The reaction of 1 with NaBH4, in THF yields intermediary tetrahydroborate complexes (η5-C5Me5)Ru(PR3)(BH4) (3), which are converted to the trihydrides 2 by treatment with ethanol. Irradiation of 2c and 2f in C6D6 solution with UV light causes H/D exchange reaction among the solvent, hydride ligands, and the coordinated phosphine.  相似文献   

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