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1.
Ntaoleng M. Makunya Reinout Meijboom Alfred Muller 《Journal of organometallic chemistry》2005,690(18):4159-4167
Cyclopentadienyldicarbonylmethyliron, [CpFe(CO)2Me] (1), undergoes migratory carbonyl insertion under the influence of isosteric phosphine ligands P(4-FC6H4)3 and P(4-MeC6H4)3. The products of the reaction, [CpFe(CO)(COMe)P(4-FC6H4)3] (2a) and [CpFe(CO)(COMe)P(4-MeC6H4)3] (2b), were characterised by X-ray crystallography. In both structures, the iron atom adopts a pseudo octahedral coordination geometry. Fe-P bond distances are the same at 2.1932(8) Å in 2a and 2b, respectively. Thus, contrary to what was expected, X-ray data could not be used to quantitatively differentiate between the two phosphine ligands in 2a and 2b. Therefore, additional spectroscopic techniques such as IR and NMR were employed. Similarly, the Fe-C bond lengths of the carbonyl (Fe-CO) and acetyl (Fe-COMe) are 1.748(3) and 1.955(3) in 2a, and 1.744(3) and 1.951(3) Å in 2b, respectively.The migratory carbonyl insertion was studied by NMR, IR, and UV-vis spectroscopies to determine the mechanism and the rate law. Results from NMR spectroscopy show that the formation of the product is accompanied by oxidation of the corresponding phosphine ligand. An increase in the reactivity of migratory carbonyl insertion for P(4-MeC6H4)3 was observed when the solvent was changed from CH2Cl2 to MeCN. The kinetic data showed that P(4-MeC6H4)3 reacts faster than P(4-FC6H4)3. 相似文献
2.
I. V. Skabitskii A. A. Pasynskii M. V. Karpacheva 《Russian Journal of Coordination Chemistry》2013,39(12):844-848
The heterometallic complex (CO)3(PPh3)Re(μ-SPr)Pt(PPh3)(CO) (I) was formed in the reaction of Re2(μ-SPr)2(CO)8 with (PPh3)2Pt(C2Ph2), together with (CO)3(PPh3)Re(μ-SPr)2Re(CO)4 (II), which was also prepared by an alternative synthesis. Compounds I and II were characterized by X-ray diffraction. In I, the Re-Pt single bond, 2.7414(5) Å, is supplemented by a thiolate bridge with shortened bonds: Pt-S (2.336(2) Å) and Re-S (2.449(2) Å). The Re-P (2.469(2) Å) and Pt-P (2.329(2) Å) bonds are also shortened. Complex II resulting from replacement of one CO group in the starting rhenium complex by triphenylphosphine has no M-M bond, and the Re-S and Re-P bond lengths (2.511(2)–2.527(2) and 2.517(3) Å) are close to the length of single bonds. It is assumed that the platinum atom in I is attached to the formally double bond Re ? SPr arising upon dissociation of Re2(μ-SPr)2(CO)8. 相似文献
3.
The first tertiary arsine-stabilised arsenium salts, [(L)AsMePh]OTf (L = Ph3As, Me2PhAs, [2-(MeOCH2)C6H4]Ph2As, [2-(MeOCH2)C6H4]Me2As), have been prepared by chloride abstraction from chloromethylphenylarsine with trimethylsilyl triflate in the presence of the arsine. The complexes have been characterised by crystallography and 1H NMR spectroscopy. The chiral cations in the complexes have structures based on the trigonal pyramid in which the arsine is coordinated orthogonally to the prochiral, six-electron MePhAs+ ion that forms the base of the pyramid. The NMR data for the complexes in dichloromethane-d2 are consistent with rapid exchange of the arsine on the arsenium ion, even at 183 K. The corresponding phosphine-stabilised complexes are considerably more stable than their arsine counterparts in dichloromethane-d2 with the free energy of activation DeltaG = ca. 60 kJ mol(-1) being calculated for phosphine exchange in [(Me2PhP)AsMePh]OTf at 281 K; for [(Me2[2-(MeOCH2)C6H4]P)AsMePh]OTf in the same solvent, DeltaG = ca. 70 kJ mol(-1) at 323 K. 相似文献
4.
《Journal of Inorganic and Nuclear Chemistry》1976,28(12):2231-2237
Complexes of the type ReOX3L2, ReNX2L3, ReX3(NO)L2 and ReX2(NO)L3 have been studied using, UV visible, IR and H1, C13 NMR spectroscopy. (X is a halogen, Cl, Br, I and L is a tertiary phosphine Et3P and Et2PhP). Evidence obtained on the blue cis isomer ReOCl3L2 suggests that the halogens are arranged on a face of the octahedral complex. Assignments of v(Re-X) and v(Re-P) vibrations have been made. Three complexes of technetium, [TcCl4(Ph3P)2], [TcCl3(Et2PhP)3] and [TcCl3(NO)(Et2PhP)2] have been isolated. 相似文献
5.
K. B. Yatsimirskii M. I. Kabachnik Z. A. Sheka T. Ya. Medved E. I. Sin E. I. Sinyavskaya Yu. M. Polikarpov 《Theoretical and Experimental Chemistry》1971,4(4):284-287
Reaction of alkali metal halides (MX) with methylenediphosphine oxides and various related compounds in nonaqueous solutions leads to the formation of complex compounds. The compositions, properties, and stabilities of these compounds, which have been studied in detail in acetonitrile, are determined by the nature of the cations and anions of the alkali metal halides. Formation of neutral complexes with the composition [MX · L] and cationic complexes with the composition [ML]+ has been established. The most characteristic representative of complexes of the first type is [NaI · L]; in the complexes studied, L=R2P(O)CH2P(O)R2 (R=Bu, BuO, or Ph), Ph2P(O)CH2P(O) (OC2H5)CH2P(O)Ph2 and (p-OCH3C6H4)2P(O)CH2P(O)(C6H4CF3-p)2. Compound [LiL]+ is characteristic of complexes of the second type; the compounds containing Ph3P(O), Ph2P(O)CH2P(O)Ph2, and Ph2P(O)CH2P(O)(OC2H5)CH2P(O)Ph2 as ligands have been studied. Stability constants of the complexes [NaI · L] and [LiL]+ have been determined by measuring the dependence of the electrical conductivity of solutions of the alkali metal halides in acetonitrile on the concentration of the ligands. The complex-forming power of phosphine oxides increases with increase in the number of P=O groups. Stabilities of the complexes [NaI · L] with ligands with identical structure decrease with increase in the electronegativity of the substituents on the phosphorus atoms. 相似文献
6.
A.G. Ginzburg B.V. Lokshin V.N. Setkina D.N. Kursanov 《Journal of organometallic chemistry》1973,55(2):357-361
From IR-spectroscopic studies it is shown that phosphine derivatives of cyclopentadienylmanganese tricarbonyl interact reversibly with SnCl4 and another Lewis acids in CH2Cl2 solution. The structures of the resulting complexes are discussed. Complex formation is favoured as the electron-donor properties of both the π-ring substituents and of the phosphine ligands attached to manganese atom are increased. The ability of Lewis acids to undergo such complex formation follows the series: SnCl4 > SbCl3 > HgCl2 > GeCl4. 相似文献
7.
Conclusions 5-RC5H4Mn(CO)(P)2 complexes, where (P)2 is a bidentate phosphine, or (P) is Ph2PMe or (EtO)3P, are organometailic Lewis bases, and undergo protonation at the Mn atom in the presence of CF3COOH. The protonated forms display square pyramidal configurations and exist in the form of cis- and trans-isomers, depending on the nature of the phosphine ligand and the protonation conditions.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1388–1392, June, 1987.For Communication No. 19, see [1]. 相似文献
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9.
Two silylene nickel carbonyl complexes of composition L·Ni(CO)(3) (1) {L = PhC(NtBu)(2)SiCl} and L'(2)·Ni(CO)(2) (2) { L' = RSiCl(2), R = (1,3-bis-(2,6-diisopropylphenyl)imidazol-2-ylidene)} were prepared by reacting 1 equivalent of Ni(CO)(4) with 1 equivalent of heteroleptic chlorosilylene L for 1 and with 2 equivalents of carbene stabilized dichlorosilylene L' for 2 in toluene at room temperature. Both complexes 1 and 2 were characterized by single-crystal X-ray analysis, NMR and IR spectroscopy, EI-MS spectrometry, and elemental analysis. 相似文献
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11.
The reactions of dimeric complex [Rh(CO)2Cl]2 with hemilabile ether‐phosphine ligands Ph2P(CH2) nOR [n = 1, R = CH3 (a); n = 2, R = C2H5 (b)] yield cis‐[Rh(CO)2Cl(P ~ O)] (1) [P ~ O = η 1‐(P) coordinated]. Halide abstraction reactions of 1 with AgClO4 produce cis‐[Rh(CO)2(P ∩ O)]ClO4 (2) [P ∩ O = η 2‐(P,O)chelated]. Oxidative addition reactions of 1 with CH3I and I2 give rhodium(III) complexes [Rh(CO)(COCH3)ClI(P ∩ O)] (3) and [Rh(CO)ClI2(P ∩ O)] (4) respectively. The complexes have been characterized by elemental analyses, IR, 1H, 13C and 31P NMR spectroscopy. The catalytic activity of 1 for carbonylation of methanol is higher than that of the well‐known [Rh(CO)2I2]? species. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
12.
Adriano Duatti Roberto Rossi Luciano Magon Ulderico Mazzi Edoardo Roncari 《Transition Metal Chemistry》1982,7(4):199-201
Summary The Re(CO)2(L)P2 complexes (L=N-methylsalicylideneiminate,N-phenylsalicylideneiminate, halfN,N-ethylenebis(salicylideneiminate) or 8-hydroxyquinolinate; P=dimethyl(phenyl)phosphine or triphenylphosphine) were synthesized from the ReCl(CO)3P2 complexes and characterized by elemental analysis, i.r. and1H n.m.r. spectroscopy. 相似文献
13.
《Journal of organometallic chemistry》1987,319(2):213-217
Trimethylamine N-oxide (TMNO)-initiated decarbonylations of Mo(CO)6 followed by phosphine additions yield the complexes Mo(CO)5(Ph2PCH2PPh2), which consists of a unidentate diphosphine, and the dinuclear phosphine-bridged complexes Mo2(CO)10(μ-Ph2P(CH2)nPPh2) (where n = 2, 3) at ambient temperatures. The IR and NMR (1H and 31P) spectroscopic and structural properties of these complexes are presented and discussed. Some thermal analytical data are summarised. 相似文献
14.
《Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy》1988,44(11):1219-1223
Far i.r. spectra are reported for 34 adducts of phosphine and amine bases with copper (I) halides in which the copper atom is coordinated to only one terminal halide. CuX stretching frequencies are assigned for all of the chloro complexes and for most of the bromo and iodo complexes. The CuX stretching frequencies have been found to depend primarily on the CuX̵ bond length, and appear to be relatively independent of the nature of the coordinating ligands. Best fit curves to the experimental data correspond to a dependence of ν(CuX) on the inverse nth power of r(CuX), where n is approximately equal to 5. Metal—halogen bond stretching force constants have been calculated for copper(I) and related silver(I) and gold(I) halide complexes assuming that the MX entity behaves as an uncoupled diatomic molecule. The results show that for three-coordinate copper(I) the force constants decrease in the order CuCl>CuBr>CuI and that the same trend is shown for four-coordinate copper(I) complexes, but the differences are considerably smaller than for the three-coordinate case. Analogous trends are found for the two- and three-coordinate gold compounds. 相似文献
15.
Baya M Houghton J Konya D Champouret Y Daran JC Almeida Leñero KQ Schoon L Mul WP van Oort AB Meijboom N Drent E Orpen AG Poli R 《Journal of the American Chemical Society》2008,130(32):10612-10624
Reduction of compound "Pd(bcope)(OTf)2" [bcope = (c-C8H14-1,5)PCH2CH2P(c-C8H14-1,5); OTf = O3SCF3] with H2/CO yields a mixture of Pd(I) compounds [Pd2(bcope)2(CO)2](OTf)2 (1) and [Pd2(bcope)2(mu-CO)(mu-H)](OTf) (2), whereas reduction with H2 or Ph3SiH in the absence of CO leads to [Pd3(bcope)3(mu3-H)2](OTf)2 (3). Exposure of 3 to CO leads to 1 and 2. The structures of 1 and 3 have been determined by X-ray diffraction. Complex [Pd2(bcope)2(CO)2](2+) displays a metal-metal bonded structure with a square planar environment for the Pd atoms and terminally bonded CO ligands and is fluxional in solution. DFT calculations aid the interpretation of this fluxional behavior as resulting from an intramolecular exchange of the two inequivalent P atom positions via a symmetric bis-CO-bridged intermediate. A cyclic voltammetric investigation reveals a very complex redox behavior for the "Pd(bcope)(OTf)2"/CO system and suggests possible pathways leading to the formation of the various observed products, as well as their relationship with the active species of the PdL2(2+)/CO/H2-catalyzed oxo processes (L2 = diphosphine ligands). 相似文献
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17.
Effective and convenient syntheses of solenopsin A and B have been developed which involve the Beckman rearrangement-alkylation reaction promoted by organoaluminum reagents and a new stereoselective reduction of imino functional group. 相似文献
18.
Xu-Feng Liu 《Transition Metal Chemistry》2016,41(5):547-554
Reaction of [μ-SC6H3(CH3)S-μ]Fe2(CO)6 (1) with 2 equivalents of PPh3 gave the monosubstituted complex [μ-SC6H3(CH3)S-μ]Fe2(CO)5(PPh3) (2) plus the disubstituted [μ-SC6H3(CH3)S-μ]Fe2(CO)4(PPh3)2 (3), while the complexes [μ-SC6H3(CH3)S-μ]Fe2(CO)5[P(3-C6H4CH3)3] (4) and [μ-SC6H3(CH3)S-μ]Fe2(CO)5[P(4-C6H4F)3] (5) were prepared by the reactions of 1 with P(3-C6H4CH3)3 or P(4-C6H4F)3 in the presence of Me3NO. Complexes 3–5 were characterized by IR, NMR spectroscopy and single-crystal X-ray diffraction analysis. The molecular structures of 3–5 reveal that in each case, the phosphine ligand occupies the apical position in an overall distorted square pyramidal iron(I) complex geometry. 相似文献
19.
《Journal of organometallic chemistry》1992,426(2):C25-C27
The novel d2 niobium nitrene complex (η-C5Me5)Nb(NAr)(PMe3)2 (Ar=2,6-iPr2C6H3) (1) is accessible via 相似文献
20.
Promotion of acetophenone formation from methyl(phenyl)rhodium carbonyl complexes by organic halides
Glenn J. Sunley Francesco P. Fanizzi Isabel M. Saez Peter M. Maitlis 《Journal of organometallic chemistry》1987,330(3):C27-C30
[C5Me5RhPh(CO)CH3] reacted thermally to give acetophenone (27%) and toluene (9%); acetophenone formation was substantially increased in the presence of halobenzenes PhX (the order of effectiveness being X = I> Br> Cl) or methyl iodide, but 1-electron oxidisers promoted C---C coupling (toluene formation). 相似文献