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1.
Alkynylnickel complexes trans-C6Cl5Ni(PPhMe2)2CCR (IIIa, R H; IIIb, R Me; IIIc, R Et; IIId, R CH2OH; IIIe, R CH2CH2OH; IIIf, R Ph; IIIg, R C6H4OMe-p) have been prepared from trans-[C6Cl5Ni-(PPhMe2)2L]ClO4 and monosubstituted acetylenes in the presence of triethylamine, and their reactions with alcohols in the presence of perchloric acid were studied. Complexes IIIa and IIIe afforded alkoxycarbene complexes trans-[C6Cl5Ni-(PPhMe2)2{C(OR′)Me}]ClO4 (IVa, R′ Me; IVb, R′ Et; IVc, R′ n-Pr) or trans-C6Cl5Ni(PPhMe2)2{}]ClO4(IVd), respectively, but IIIb either decomposed or afforded trans-C6Cl5Ni(PPhMe2)2CHC(OMe)Me, depending on the amount of acid used. Treatment of IVaIVd with amines resulted in deprotonation to give α-alkoxyvinyl complexes, trans-C6Cl5Ni(PPhMe2)2C(OR′)CH2 (VIaVIc) or trans-C6Cl5Ni(PPhMe2)2 (VId), the reaction being reversible. A 1H NMR study indicated: (i) that the carbene methyl and the vinyl protons IV or VI are D-exchangeable by MeOD without catalyst; (ii) that the basicity of VIa is comparable to those of amines; (iii) that the carbene complexes IVaIVc have two isomers due to hindered rotation about the C(carbene)O bond in solution, IVb existing in the Z-form in the solid state; (iv) that the rotationalbarriers (°G≠) about the C(carbene)O bond in IVb and the NiC-(carbene) bond in IVd are 20 (or more) and 11.7 kcal/mol, respectively. These results are explained in term of double bond character of the carbene carbon and its surrounding atoms. 相似文献
2.
《Journal of organometallic chemistry》1987,323(3):C47-C50
Reaction of RCCH (R Ph, CO2Meor CO2Et) with trans-[M(N2)2(dppe)2] (M Mo or W; dppe Ph2PCH2CH2PPh2) or [Mo(dppm)3] (dppm Ph2PCH2PPh2) gives the alkyne complexes [M(RCCH)2(diphos)2] (diphos dppe, M Mo, R = Ph; dihpos dppm, M Mo, R Ph or CO2Me) and the alkynyl complexes trans-[M(cCR)2(dppe)2], [MH2(CCR)2 (dppe)2] (M Mo or W. R Ph, CO2Me or CO2Et) and cis-[WH(CCCO2Me)(dppe)2]: the X-ray structure of trans-[Mo(CCPh)2(dppe)2] is reported. 相似文献
3.
Internally consistent assignments of the 31P-{1H} NMR parameters of the complexes [Pt(RCCR′)(PPh3)2] are proposed, based on the premise that the magnitude of 1J(PtP) depends mainly on the nature of the moiety CR trans to P. For a given R, 2J(PP) correlates with 1J(PtP) for thebond trans to CR. The alkynes PhCCSnEt3, PhCCSnPh3, Me3SiCCCl, Me3SiCCBr, Et3SiCCI and MeCCI undergo oxidative addition reactions with [Pt(C2H4)(PPh3)2]; the intermediate alkyne complex was detected for PhCCSnEt3, Me3SiCCCl and Me3CCBr. The triyne Me(CC)3Me forms platinum(0) complexes by coordination with the central or terminal CC bond and appears also to give a platinum(II) complex by oxidative addition. 相似文献
4.
H.David Empsall Bernard L. Shaw Anthony J. Stringer 《Journal of organometallic chemistry》1975,94(1):131-138
Several new platinum(II) acetylide complexes, trans-{Pt[CCCR1R2(OR3)]2-L2} (R1, R2 H, Me, Et; CR1R2 cyclohexylidene; R3 H, Me or Ph), trans-[Pt(CCCH2CH2OH)2L2], trans-[Pt(p-tolylacetylide)2L2] and trans-[PtX(p-tolylacetylide)L2] (L PMe2Ph or in one case, AsMe2Ph) have been prepared. Platinum(II) acetylide complexes with tertiary hydroxyl groups are easily dehydrated by acetic anhydride/pyridine to give platinum-enyne complexes. Analogous compounds with primary hydroxyl groups do not dehydrate but give acetates. 1H and 13C NMR data are given and the shift reagent Eu(fod)3 was used to analyse the 1H NMR spectrum of trans-[Pt(CCCH2CH2OH)2(PMe2Ph)2]. 相似文献
5.
《Journal of organometallic chemistry》1988,346(3):C53-C57
The 16-electron fragment (NP3)Rh+ inserts in a highly stereospecific manner across CH bonds from acetylene and 1-alkynes to give the octahedral cis-(alkynyl)hydrides [(NP3)Rh(H)(CCR)]BPh4 (R = H, Ph, COOEt). The structure of the cis-(ethynyl)hydride [(NP3)Rh(H)(CCH)]BPh4 · 1.5 THF has been established by X-ray diffraction. The trigonal bipyramidal rhodium(I) complex [(NP3)RhH], reacts with terminal alkynes to give H2 and the neutral σ-acetylides [(NP3)Rh(CCR)] (R = Ph, COOEt). These undergo metathesis between terminal alkynes and the σ-acetylide ligand through a mechanism involving consecutive breaking and making of CH bonds. 相似文献
6.
Preparation and properties of the diamagnetic planar complexes trans-[p-C6H4(CCPd(X)(PEt3)2)2] (X = Cl, Br, I, NCS) and trans-[p-C6H4(CCPd(X)(PEt3)2)2](ClO4)2 (X = PEt3, pyridine) are described. The structures of the compounds have been determined by 31P and 1H NMR spectroscopy. The IR spectra are discussed. 相似文献
7.
[WBr2(CO4]n reacts with alkynes to give complexes [WBr2CO(RCCR)2]2 (1) (R = R′ = Me, Et, Ph; R = Me, R′ = Ph), which react with nucleophiles L{L = CNBut, PPh3, or P(OMe)3} to give monoalkyne derivatives (WBr2(CO)(RCCR′)L2](2). An intermediate bis-alkyne adduct [WBr2CO(MeCCMe)2(CNBut)] (3) was isolated in the reaction of [WBr2CO(MeCCMe)2]2 with CNBut illustrating that cleavage of the dimer (1) is the first stage in these reactions. 相似文献
8.
《Journal of organometallic chemistry》1991,414(2):C51-C53
The complexes trans-[Ru(PMe3)4(CCPh)2] and trans-[Ru(PMe3)4(CCC6H4C6H4CCSnMe3)2] have been prepared from the reaction between trans-[Ru(PMe3)4Cl2] and an excess of either Me3SnCCPh or Me3SnCCRCCSnMe3 (R = p-C6H4C6H4), respectively. However, if only one equivalent of the latter reagent is used the rod-like polymeric species trans-[-Ru(PMe3)4CCRCC-]n can be isolated. 相似文献
9.
Reduction of various pentafluorophenylnickel(II) complexes in the presence of phosphines gives unstable nickel(I) compounds but Ni(C6F5)(CO)2(PPh3)2 is isolated in the presence of CO. Similar NiR(CO)2(PPh3)2 (R = C6F5,C6Cl5, 2,3,5,6-C6Cl4H) are obtained by reaction of the halogenonickel(I) complex with MgRBr or LiR. Reduction of NiX2L2 in the presence of acetylenes gives [NiXL2]2(μ-PhCCR) (R = H, X = Cl and R = Ph, X = Cl, Br) when L = P-n-Bu3 but only NiX(PPh3)3 are recovered when L = PPh3. No reaction with the alkyne is observed for [NiX(PPh3)2]n but [NiCl(PPh3)]n reacts with RCCR′ to give paramagnetic NiCl(PPh3)(CRCR′) (R = Ph, R′= H, COOEt), diamagnetic [NiCl(PPh3)]2(μ-PhCCPh) and cyclotrimerization when R = R′ = COOMe. Chemical and structural behaviour of the new nickel(I) complexes is described. 相似文献
10.
E. Jóna T. Šramko P. Ambrovič J. Gažo 《Journal of Thermal Analysis and Calorimetry》1972,4(2):153-160
The decomposition heats (ΔH) for complexes of the type Ni(NCS)2L2 were studied by means of a differential scanning calorimeter. From the decreasing values ofΔH the following order has been established:a) for pseudooctahedral complexes: py >β-pic > > Q; andb) for square-planar complexes: 2,6-lut > Q >α-pic. The results obtained are compared with the data from the TG, DTG, and DTA curves. 相似文献
11.
Cationic alkoxycarbene complexes of platinum(II) have been isolated in the reactions of trans-[(PR3)2PtX(R′OH)]PF6 (X H or Me; R′ Me or Et) with Me3SiCCR′′ (R′′ H, Me or SiMe3). In these reactions cleavage of the carbon-silicon bond by the nucleophilic attack of alcohol has been observed. These carbene complexes have been characterized by elemental analyses and by IR, 1H and 13C NMR spectral data. 13C NMR chemical shift data for carbene carbon atoms suggest that the carbene carbon may be very positively charged. 相似文献
12.
《Journal of organometallic chemistry》1989,367(3):C18-C20
Reactive CO-free monocyclopentadienylvanadium(I) complexes CpV(η2-RCCR′)(PMe3)2 (R,R′ = Ph,Ph; Ph,Me; Et,Et) can be synthesized by Mg reduction of CpVCl2(PMe3)2 in the presence of free alkyne. Reaction with a second alkyne, or use of diynes in the reduction, produces metallacycles with the metallacyclopentatriene structure. 相似文献
13.
[Pt(C2O4)(dppe)] reacts thermally with PhCCH to produce [Pt(CCPh)2(dppe)], which has been prepared by alternative routes. Similar treatment of [Pt(C2O4)(dppm)] initially produces [Pt(CCPh)2(dppm)], which rearranges to give cis,cis-[Pt2(CCPh)4(μ-dppm)2]. Reaction of [PtCl2(dppm)] with PhCCH/KOH/18-crown-6, or with (PhCC)SnMe3, gives [Pt(CCPh)2(dppm)], which may be converted to the cis,cis-dimer by addition of oxalic acid. Ultraviolet irradiation or refluxing with a trace amount of dppm converts [Pt(CCPh)2(dppm)] to trans,trans-[Pt2(CCPh)4(μ-dppm)2], but the cis,cis-dimer is stable under these conditions. [Pt(C2O4)L2] (L = PPh3, PEt3) complexes also react thermally with PhCCH to yield [Pt(CCPh)2L2] species. 相似文献
14.
The reaction of cis-[PdCl2(CNR)2] (R = Ph, p-MeC6H4, p-MeOC6H4) and trans-[PdI2(CNPh)2] with HgR′2 (R′ = Me, Ph) followed by addition of PPh3 (Pd/PPh3, ) gives complexes of the type trans- [PdX {C(=NR)C(R′)=NR}(PPh3)2] (X = Cl, I) I as main products. These bis(imino) compounds may result from double insertion of the coordinated isocyanides into a PdR′ σ-bond. NaBPh4 was also found to act like HgPh2 as a good phenylating agent towards coordinated isocyanide. The reactions of I with methanolic HClO4 yield cationic compounds: trans- [PdX{C(NHR)C(R′)=NR}(PPh3)2]ClO4; the protonated bis(imino) group may also be formulated as {C(=NR)C(R′)NHR} and a fast equilibrium between the two forms probably exists in solution. The factors influencing the reaction with HgR′2 and spectroscopic data (IR and 1H NMR) for the complexes are reported and discussed. 相似文献
15.
Camino Bartolomé Jose Miguel Martín-Alvarez Fernando Villafañe 《Journal of organometallic chemistry》2006,691(18):3862-3873
Halide abstraction from [Pd(μ-Cl)(Fmes)(NCMe)]2 (Fmes = 2,4,6-tris(trifluoromethyl)phenyl or nonafluoromesityl) with TlBF4 in CH2Cl2/MeCN gives [Pd(Fmes)(NCMe)3]BF4, which reacts with monodentate ligands to give the monosubstituted products trans-[Pd(Fmes)L(NCMe)2]BF4 (L = PPh3, P(o-Tol)3, 3,5-lut, 2,4-lut, 2,6-lut; lut = dimethylpyridine), the disubstituted products trans-[Pd(Fmes)(NCMe)(PPh3)2]BF4, cis-[Pd(Fmes)(3,5-lut)2(NCMe)]BF4, or the trisubstituted products [Pd(Fmes)L3]BF4 (L = CNtBu, PHPh2, 3,5-lut, 2,4-lut). Similar reactions using bidentate chelating ligands give [Pd(Fmes)(L-L)(NCMe)]BF4 (L-L = bipy, tmeda, dppe, OPPhPy2-N,N′, (OH)(CH3)CPy2-N,N′). The complexes trans-[Pd(Fmes)L2(NCMe)]BF4 (L = PPh3, tht) (tht = tetrahydrothiophene) and [Pd(Fmes)(L-L)(NCMe)]BF4 (L-L = bipy, tmeda) were obtained by halide extraction with TlBF4 in CH2Cl2/MeCN from the corresponding neutral halogeno complexes trans-[Pd(Fmes)ClL2] or [Pd(Fmes)Cl(L-L)]. The aqua complex trans-[Pd(Fmes)(OH2)(tht)2]BF4 was isolated from the corresponding acetonitrile complex. Overall, the experimental results on these substitution reactions involving bulky ligands suggest that thermodynamic and kinetic steric effects can prevail affording products or intermediates different from those expected on purely electronic considerations. Thus,water, whether added on purpose or adventitious in the solvent, frequently replaces in part other better donor ligands, suggesting that the smaller congestion with water compensates for the smaller M-OH2 bond energy. 相似文献
16.
Tetracloro-o-benzoquinone reacts with (diphenylacetylene)bis(tirphenylphosphine)platinum(0) to give the novel platinum(II) diphenylacetylene complex, Pt(C6Cl4O2)PhCCPh)(PPh3), (I), which reacts with hydrogen halides to give the compelexes cis-PtX2(PhCCPh((PPh3), (X = Cl or Br). Hydrogen chloride also readily removes the tetrachloro-o-benzoquinoneligand from the adducts Ni(C6Cl4O2)(Ph2PCH2CH2PPh2) and M(C6Cl4O2)(PPh3)2, (M = Pd or Pt) but it has no reaction upon Ir(Cl)(C6Cl4O2)(CO)(PPh3)2 at room temperature. The acetylene in (1) is susceptible to nucleophilic attact and reaction with diethylamine gives the vinyl adduct Pt(C6Cl4O2)(CPhCPh)NHEt2)(PPh3). Other reactions of (I) have also been studied. Attemps to prepare other olefin or acetylene complexes of platinum(II) by the action of tetrachlor-o-benzoquinone on the complexes Pt(L)(PPh3)2, (L = PhCCH,(Et)(Me)(HO)CCCC(OH)(Me)(Et), HOCH2OH, CF3CCCF3, CF2CF2, CF2CH2 or trans-PhCHCHPh) are also described. 相似文献
17.
《Journal of organometallic chemistry》1987,331(1):63-72
Bis(η-cyclopentadienyl)hydridorhenium Cp2ReH undergoes stereospecific trans insertion reactions when treated with monosubstituted acetylenes HCCR (R CO2Me, CN, CF3). The cis alkenyl complexes Cp2Re[η1-(Z)-CHCHR] thus formed isomerize thermally or under acid catalysis to produce the trans isomers Cp2Re[η1-(E)-CHCHR]. When Cp2ReH adds to HCCCOMe only the trans isomer is observed. The regiospecific β-addition of Cp2ReH contrasts with the α-addition of Cp2MoH2 and Cp2WH2. The insertion of acetylenes HCCR′ into the metalcarbon bond of some alkenyl complexes Cp2Re[η1-(E)-CHCHR] affords butadienyl complexes Cp2Re[η1-{(1E,3E)-CHCHR′CHCHR&}] (R,R′ COMe, CO2Me). The (E,E)-configuration of these compounds is deduced from 3J(13-C1H) coupling constants. 相似文献
18.
《Journal of organometallic chemistry》1992,423(3):C43-C47
Bis(acetylides) and bis(diacetylides) of ruthenium(II), trans-Ru(CO)2(PEt3)2(CCR)2 (1) (1a, R Ph; 1b, R tBu; 1c, R SiMe3; 1d, R H) and trans-Ru(CO)2(PEt3)2(CCC CR)2 (2) (2a, R SiMe3; 2b, R H) have been synthesized and characterised. The first single crystal X-ray analyses of these all trans-acetylides have revealed linear C2RuC2 chains in 1a and 1d. 相似文献
19.
20.
Duanjun Xu Kunio Miki Yasushi Kai Nobutami Kasai Masanori Wada 《Journal of organometallic chemistry》1985,287(2):265-273
The structure of a nickel(II) complex, trans-[Ni(C6Cl5)(PMe2Ph)2{C(OMe)Me}]BF4, containing the simplest alkyl(alkoxy)carbene ligand has been determined by X-ray crystallography (R = 0.091). The geometry around the nickel atom is square-planar. The comparatively short NiC(1) bond length of 1.843(10) Å showed the presence of π-bonding in the nickel-carbene bond. 相似文献