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1.
2.
Reaction of P2Ph4 with the diyne-diol complex [{Co2(CO)6}2(μ-η2:μ-η2-HOCH2CCCCCH2OH)] in toluene at 65 °C gives [{Co2(μ-P2Ph4)(CO)4}{Co2(CO)6}(μ-η2:μ-η2-HOCH2CCCCCH2OH)] (1). Thermolysis of 1 at 95 °C leads to [{Co2(CO)5}2(μ-P2Ph4)(μ-η2:μ-η2-HOCH2CCCCCH2OH)](2) and (μ2-PPh2)(μ2-CO)(CO)7] (3). The structures of 1-3 have been established by X-ray crystallography. In 1, a pseudoequatorial P2Ph4 ligand bridges the cobalt-cobalt bond of a Co2(CC)(CO)4 unit. By contrast, in isomeric 2, a pseudoaxial P2Ph4 ligand spans two Co2(CC)(CO)5 units, a new coordination mode for [{Co2(CO)5L}2(μ-η2:μ-η2-diyne)] complexes. Complex 3 arises from dehydration-cyclocarbonylation of the diyne-diol in 1 to give a 2(5H)-furanone, a process that has not been previously reported. Reaction of HOCH2CCCCCH2OH with [Co2(μ-PPh2)2(CO)6] at 80 °C in toluene gave [Co3(μ-PPh2)3(CO)6], [Co2(CO)6(μ-η2-HOCH2CCCCCH2OH)] and [Co2{μ-η4-PPh2C(CCCH2OH)C(CH2OH)CO}(μ-PPh2)(CO)4] (4). The regiochemistry of 4 was confirmed by X-ray crystallography.  相似文献   

3.
The synthesis and properties of heterobimetallic Ti-M complexes of type {[[Ti](μ-η12-CCSiMe3)][M(μ-η12-CCSiMe3)(CO)4]} (M = Mo: 5, [Ti] = (η5-C5H5)2Ti; 6, [Ti] = (η5-C5H4SiMe3)2Ti; M = W: 7, [Ti] = (η5-C5H5)2Ti; 8, [Ti] = (η5-C5H4SiMe3)2Ti) and {[Ti](μ-η12-CCSiMe3)2}MO2 (M = Mo: 13, [Ti] = (η5-C5H5)2Ti; 14, [Ti] = (η5-C5H4SiMe3)2Ti). M = W: 15, [Ti] = (η5-C5H5)2Ti; 16, [Ti] = (η5-C5H4SiMe3)2Ti) are reported. Compounds 5-8 were accessible by treatment of [Ti](CCSiMe3)2 (1, [Ti] = (η5-C5H5)2Ti; 2, [Ti] = (η5-C5H4SiMe3)2Ti) with [M(CO)5(thf)] (3, M = Mo; 4, M = W) or [M(CO)4(nbd)] (9, M = Mo; 10, M = W; nbd = bicyclo[2.2.1]hepta-2,5-diene), while 13-16 could be obtained either by the subsequent reaction of 1 and 2 with [M(CO)3(MeCN)3] (11, M = Mo; 12, M = W) and oxygen, or directly by oxidation of 5-8 with air. A mechanism for the formation of 5-8 is postulated based on the in-situ generation of [Ti](CCSiMe3)((η2-CCSiMe3)M(CO)5), {[Ti](μ-η12-CCSiMe3)2}-M(CO)4, and [Ti](μ-η12-CCSiMe3)((μ-CCSiMe3)M(CO)4) as a result of the chelating effect exerted by the bis(alkynyl) titanocene fragment and the steric constraints imposed by the M(CO)4 entity.The molecular structure of 5 in the solid state were determined by single crystal X-ray diffraction analysis. In doubly alkynyl-bridged 5 the alkynides are bridging the metals Ti and Mo as a σ-donor to one metal and as a π-donor to the other with the [Ti](CCSiMe3)2Mo core being planar.  相似文献   

4.
The study of the reactivity of the cyclopalladated complex [Pd{[(η5-C5H3)-CHN-(C6H4-2-SMe)]Fe(η5-C5H5)}Cl] (1c) with the alkynes R1-CC-R1 (with R1 = CO2Me, Ph or Et) is reported.Compound 1c reacts with the equimolar amount of MeO2C-CC-CO2Me in refluxing CH2Cl2 to give [Pd{[(MeO2C-CC-CO2Me)(η5-C5H3)-CHN-(C6H4-2-SMe)]Fe(η5-C5H5)}Cl] (2c), which arises from the monoinsertion of the alkyne into the σ[Pd-C(sp2, ferrocene)] bond.However, when the reaction was performed using Ph-CC-Ph or Et-CC-Et no evidence of the insertion of these alkynes into the σ[Pd-C(sp2, ferrocene)] bond was detected.In contrast with these results, when 1c was treated with the Tl[BF4] followed by the removal of the TlCl formed and the subsequent addition of MeO2C-CC-CO2Me the reaction gave 2c and [Pd{[(MeO2C-CC-CO2Me)25-C5H3)-CHN-(C6H4-2-SMe)]Fe(η5-C5H5)}][BF4] (3c); but when the alkyne was R1-CC-R1 (with R1 = Ph or Et), the ionic palladacycles [Pd{[(R1-CC-R1)25-C5H3)-CHN-(C6H4-2-SMe)]Fe(η5-C5H5)}][BF4] · CH2Cl2 [with R1 = Ph (5c) or Et (6c)] were isolated. In compounds 3c, 5c and 6c, the mode of binding of the butadienyl unit is η3. The reactions of 2c, 3c, 5c and 6c with PPh3 are also reported. The results obtained from these studies reveal that the σ(Pd-S) bond in 2c is more prone to cleave than in 4c-6c. X-ray crystal structures of 2c, 5c and [Pd{[(MeO2C-CC-CO2Me)(η5-C5H3)-CHN-(C6H4-2-SMe)]Fe(η5-C5H5)}Cl(PPh3)] (7c), are also described. Compound 7c arises from 2c by cleavage of the Pd-S bond and the incorporation of a PPh3 in the coordination sphere of the palladium. A parallel study focused on the reactions of [Pd{[2-CH2-4,6-Me2-C6H2]-CHN-(C6H4-2-SMe)}Cl] (1d) (with a [Csp3,N,S] terdentate group) with the three alkynes reveals that the σPd-C(sp2, ferrocene)] bond of 1c is more reactive than the σ[Pd-C(sp3)] bond of 1d.  相似文献   

5.
With copper(I) iodide as catalyst, σ-alkynyls, compounds (η5-C5H5)Cr(NO)2(CC-C6H5) (5), [(η5-C5H4)-COOCH3]Cr(NO)2(CC-C6H5) (10), and [(η5-C5H4)-COOCH3]W(CO)3(CC-C6H5) (13), were prepared from their corresponding metal chloride 1, 6 and 12. Structures of compound 3, 5 and 12 have been solved by X-ray diffraction studies. In the case of 5, there is an internal mirror plane passing through the phenylethynyl ligand and bisecting the Cp ring. The phenyl group is oriented perpendicularly to the Cp with an eclipsed conformation. The twist angle is 0° and 118.4° for -CC-Ph and two NO ligands, respectively. The orientation is rationalized in terms of orbital overlap between ψ3 of Cp, dπ of Cr atom, and π of alkynyl ligand, and complemented by molecular orbital calculation. The opposite correlation was observed on the chemical shift assignments of C(2)-C(5) on Cp ring in compounds 6 and 12, using HetCOR NMR spectroscopy. The electron density distribution in the cyclopentadienyl ring is discussed on the basis of 13C NMR data and compared with the calculations via density functional B3LYP correlation-exchange method.  相似文献   

6.
The synthesis of Fc(CC)3Ru(dppe)Cp (2) from Fc(CC)3SiMe3 and RuCl(dppe)Cp is described, together with its reactions with tcne to give the tetracyano-dienyl FcCCCC{C[C(CN)2]}2Ru(dppe)Cp (3) and -cyclobutenyl FcCCCC{CCC(CN)2C(CN)2}Ru(dppe)Cp (4), with Co2(μ-dppm)n(CO)8−2n (n = 0, 1) to give FcC2{Co2(CO)6}C2{Co2(CO)6}CCRu(dppe)Cp (5) and FcCCCCC2{Co2(μ-dppm)(CO)4}Ru(dppe)Cp (6), respectively, and with Os3(CO)10(NCMe)2 to give Os33-C2CCCC[Ru(dppe)Cp]}(CO)10 (7). On standing in solution, the latter isomerises to the cyclo-metallated derivative Os3(μ-H){μ3-C[Ru(dppe)Cp]CCC[(η-C5H3)FeCp]}(CO)8 (8). X-ray structural determinations of 1, 2, 6 and 7 are reported.  相似文献   

7.
The σ-alkynyl complexes Ni(η5-C5H5)(PPh3)-CC-R (1), Ni(η5-C5H5)(PPh3)-CC-X-CCH (2) and Ni(η5-C5H5)(PPh3)-CC-X-CC-Ni(η5-C5H5)(PPh3) (3), reactwith 7,7,8,8-tetracyanoquinodimethane, TCNQ, at 30 °C by insertion of the alkyne CC into a CC(CN)2 bond to give Ni(η5-C5H5)(PPh3)-C{C6H4C(CN)2}-C{C(CN)2}-R (4), from 1, Ni(η5-C5H5)(PPh3)-C{C6H4C(CN)2}-C{C(CN)2}-X-CCH (5), from 2, and Ni(η5-C5H5)(PPh3)-C{C6H4C(CN)2}-C{C(CN)2}-X-CC-Ni(η5-C5H5)(PPh3) (6),and Ni(η5-C5H5)(PPh3)-C{C6H4C(CN)2}- C{C(CN)2}-X-C{C(CN)2}-C{C6H4C(CN)2}-Ni(η5-C5H5)(PPh3) (7),from 3 {R = (a) C6H5, (b) 4-PhC6H4, (c) 4-Me2NC6H4, (d) 1-C10H7 (1-naphthyl), (e) 2-C10H7 (2-naphthyl), (f) 9-C14H9 (9-phenanthryl), (g) 9-C14H9 (9-anthryl), (h) 3-C16H9 (3-pyrenyl), (i) 1-C20H11 (1-perylenyl), (j) 2-C4H3S (2-thienyl), (k) C10H9Fe (ferrocenyl = Fc) and (l) H; X = (a) nothing, (b) 1,4-C6H4, (c) 1,3-C6H4 and (d) 4,4′-C6H4-C6H4}. The reaction is regiospecificand the other possible insertion product, R-C{C6H4C(CN)2}-C{C(CN)2}-Ni(η5-C5H5)(PPh3) etc., is not formed. Under the same conditions, there is no evidencefor the reaction of TCNQ with the -CCH of 2, PhCCH, 1,4-C6H4(CCH)2 or FcCCH, or for the reaction of more than one CC(CN)2 of TCNQ with a Ni-alkynyl moiety. Complexes 4-7 are all air-stable, purple solids which have been characterised by elemental analysis and spectroscopy (IR, UV-Vis, 1H NMR and 13C NMR),and by X-ray diffraction for 4a, 4b and 4l. The UV-Vis spectra of 4-7 are very similar. This implies that all contain the same active chromophore which, it is suggested, is Ni-C(5)C6H4C(CN)2 and not R-C(4)C(CN)2. This isconsistent with the molecular structures of 4a, 4b and 4l which show that the first of these potentially chromophoric fragments is planar or close to it with an in-built potential for delocalisation, whilst in the second the aryl group R is almost orthogonal to the CC(CN)2 plane. The molecular structures of 4a, 4b and 4l also reveal a short Ni?C(4) separation, indicative of a Ni → C(4) donor-acceptor interaction. The electrochemistry of 4a shows aquasi reversible oxidation at ca. 1 V and complicated reduction processes. It is typical of most 4, but 4l is different in that it shows the same quasi reversible oxidation at ca. 1 V but two reversible reductions at −0.26 and −0.47 V (vs. [Fe(η5-C5Me5)2]+/0 0.0 V).  相似文献   

8.
The synthesis and properties of heterobimetallic Ti-Cd complexes of type {[Ti](μ-η12-CCR)2}CdX2 ([Ti] = Ti(η5-C5H4SiMe3)2; R = SiMe3: 3a, X = Cl; 3b, X = Br; 3c, X = I; R = Fc: 3d, X = Br; Fc = Fe(η5-C5H4)(η5-C5H5) is reported. These compounds were accessible by treatment of [Ti](CCR)2 (1a, R = SiMe3; 1b, R = Fc) with the cadmium salts CdX2 (2a, X = Cl; 2b, X = Br; 2c, X = I) in a 1:1 M ratio in diethyl ether. Dissolving, for example, 3b in tetrahydrofuran afforded coordination polymer [Cd(μ-Br)2(thf)2]n (4) along with the tweezer molecule 1a. Treatment of 3b with two equiv of LiCCFc (5) gave {[Ti](μ-η12-CCSiMe3)2}Cd(CCFc)2 (6) which eliminated at ambient temperature the all-carbon buta-1,3-diyne FcCC-CCFc (7) producing 1a and elemental Cd. The same reaction behavior was observed, when 2b was reacted with 5. The thus obtained bis(alkynyl) cadmium complex Cd(CCFc)2 (8) is redox-active at low temperature producing 7 and Cd(0). When mercury halides HgX2 (9a, X = Cl; 9b, X = Br) are used, then the titanocene dihalides [Ti]X2 (10a, X = Cl; 10b, X = Br) together with Me3SiCC-CCSiMe3 (11) and Hg(0) were formed. Nevertheless, mercury acetylides were available by treatment of Hg(OAc)2 (12) with HCCFc (13) in a 1:2 M ratio. Thus obtained Hg(CCFc)2 (14) gave with [CuBr] (15) coordination polymer [{Hg(η2-CCFc)2}(Cu2(μ-Br)2]n (16), while with [AgPF6] oxidation of the ferrocenyl moieties took place affording dicationic [Hg(CCFc)2]2+ (18).The structures of 3b and 4 in the solid state are reported. Compound 3b shows the typical characteristics for heterobimetallic organometallic π-tweezer complexes with cadmium in a tetrahedral environment, while 4 corresponds to a one-dimensional coordination polymer in which the Cd(II) ions are linked in a edge-sharing fashion by bromide bridges in the pseudo-equatorial plane. The appropriate tetrahydrofuran molecules are completing the pseudo-octahedral coordination sphere at cadmium.The cyclic voltammogram of 14 is reported showing a single reversible redox event at E0 = 0.108 V with ΔEp = 76 mV indicating that there is no communication between the Fc termini along the mercury acetylide unit.  相似文献   

9.
Heterobimetallic {cis-[Pt](μ-σ,π-CCPh)2}[Cu(NCMe)]BF4 (3a: [Pt] = (bipy)Pt, bipy = 2,2′-bipyridine; 3b: [Pt] = (bipy′)Pt, bipy′ = 4,4′-dimethyl-2,2′-bipyridine) is accessible by the reaction of cis-[Pt](CCPh)2 (1a: [Pt] = (bipy)Pt, 1b: [Pt] = (bipy′)Pt]) with [Cu(NCMe)4]BF4 (2). Substitution of NCMe by PPh3 (4) can be realized by the reaction of 3a with 4, whereby [{cis-[Pt](μ-σ,π-CCPh)2}Cu(PPh3)]BF4 (5) is formed. On prolonged stirring of 3 and 5, respectively, NCMe and PPh3 are eliminated and tetrametallic {[{cis-[Pt](η2-CCPh)2}Cu]2}(BF4)2 (6) is produced. Addition of an excess of NCMe to 6 gives heterobimetallic 3a.When instead of NCMe or PPh3 chelating molecules such as bipy (7) are reacted with 3a then the heterobimetallic π-tweezer molecule [{cis-[Pt](μ-σ,π-CCPh)2}Cu(bipy)]BF4 (8) is formed. Treatment of 8 with another equivalent of 7 produced [Cu(bipy2)]BF4 (9) along with [Pt](CCPh)2. However, when 3b is reacted with 1b in a 1:1 molar ratio then 10 and 11 of general composition [{[Pt](CCPh)2}2Cu]BF4 are formed. These species are isomers and only differ in the binding of the PhCC units to copper(I). A possible mechanism for the formation of 10 and 11 is presented.The solid state structures of 6, 10 and 11 are reported. In 11 the [{cis-[Pt](μ-σ,π-CCPh)2}2Cu]+ building block is set-up by two nearly orthogonal positioned bis(alkynyl) platinum units which are connected by a Cu(I) ion, whereby the four carbon-carbon triple bonds are unsymmetrical coordinated to Cu(I). In trimetallic 10 two cis-[Pt](CCPh)2 units are bridged by a copper(I) center, however, only one of the two PhCC ligands of individual cis-[Pt](CCPh)2 fragments is η2-coordinated to Cu(I) giving rise to the formation of a [(η2-CCPh)2Cu]+ moiety with a linear alkyne-copper-alkyne arrangement (alkyne = midpoint of the CC triple bond). In 6 two almost parallel oriented [Pt](CCPh)2 planes are linked by two copper(I) ions, whereby two individual PhCC units, one associated with each Pt building block, are symmetrically π-coordinated to Cu.  相似文献   

10.
Reaction of the doubly bridged dinuclear molybdenum complex (Me2C)(Me2Si)[(η5-C5H3)Mo(CO)3]2 (1) with benzonitrile in refluxing xylene afforded complexes (Me2C)(Me2Si)[(η5-C5H3)2Mo2(CO)4(μ-η22(⊥)-NCPh)] (2) (50%) and (Me2C)(Me2Si)[(η5-C5H3)2Mo2(CO)4(μ-η12-NCPh)] (3) (6%) with different coordination of nitrile. The corresponding μ-η22 acetonitrile and propionitrile complexes 4 and 5 could be obtained from the reactions of (Me2C)(Me2Si)(C5H4)2 with (RCN)3Mo(CO)3 (R = Me, Et) in refluxing xylene. Reactions of 1 with isonitriles generated μ-η12-CNR (R = tBu, Ph, C6H11) bridged complexes 6-8 in 53-63% yields. Subsequent reaction of 4 with Ru3(CO)12 yielded two CN bond cleavaged MoRu clusters (Me2C)(Me2Si)(η5-C5H3)2Mo2Ru3(CO)10(μ-CO)(μ3-CMe)(μ4-N) (9) (7%) and [(Me2C)(Me2Si)(η5-C5H3)2]2Mo4Ru6(CO)16(μ-CO)(μ4-CO)23122-NCMe)(μ3-CMe)(μ5-N) (10) (8%). All the new complexes have been fully characterized. The molecular structures of 2, 4, 6, 9, and 10 have been determined by X-ray diffraction analysis.  相似文献   

11.
The complexes trans-[Os(CCC6H4-4-CCR)Cl(dppe)2] (R = SiPri31, H 2), trans,trans-[(dppe)2ClOs(CCC6H4-4-CC)RuX(dppe)2] (X = Cl 3, CCC6H4-4-CCSiPri34), trans-[Os(CCC6H4-4-CCC6H4-4-CCR)Cl(dppe)2] (R = SiPri35, H 6), and trans,trans-[(dppe)2ClOs(CCC6H4-4-CCC6H4-4-CC)RuCl(dppe)2] (7) have been synthesized, and the identities of 1, 2, and 6 confirmed by single-crystal X-ray diffraction studies. Cyclic voltammetry shows that the mononuclear complexes 1, 2, 5, and 6 are oxidized at potentials within a narrow range (0.45-0.49 V), in processes centered on the osmium ethynyl neighbourhood and for simplicity assigned as OsII/III, while the heterobinuclear complexes 3, 4, and 7 exhibit lower oxidation potentials for OsII/III and a second oxidation process assigned in a similar fashion to RuII/III; the difference in potential between the Os- and Ru-localized processes decreases as the π-bridge is lengthened. UV-vis-NIR spectroelectrochemical studies on 1 and 5 reveal the appearance on oxidation of a low-energy band ascribed to chloro to metal-ethynyl charge transfer. Osmium-centered oxidation at the heterobinuclear complexes 4 and 7 results in appearance of a low-energy band, which blue-shifts and increases in intensity on further oxidation to 42+ and 72+.  相似文献   

12.
[MBr(CO)5] reacts with m-ethynylphenylamine and pyridine-2-carboxaldehyde in refluxing tetrahydrofuran to give, fac-[MBr(CO)3(py-2-CHN-C6H4-m-(CCH))] (M = Mn, 1a; Re, 2a). The same method affords the tetracarbonyl [Mo(CO)4{py-2-CHN-C6H4-m-(CCH)}] (3a) starting from [Mo(CO)4(piperidine)2]; and the methallyl complex [MoCl(η3-C3H4Me-2)(CO)2{py-2-CHN-C6H4-m-(CCH)}] (4a) from [MoCl(η3-C3H4Me-2)(CO)2(NCMe)2]. The use of p-ethynylphenylamine gives the corresponding derivatives (1b, 2b, 3b, and 4b) with the ethynyl substituent in the para-position at the phenyl ring of the iminopyridine. All complexes have been isolated as crystalline solids and characterized by analytical and spectroscopic methods. X-ray determinations, carried out on crystals of 1a, 1b, 2a, 2b, 3b, 4a, and 4b, reveals the same structural type for all compounds with small variations due mainly to the different size of the metal atoms. The reaction of complexes 1a or 2a with dicobalt octacarbonyl affords the tetrahedrane complexes [MBr(CO)3{py-2-CHN-C6H4-m-{(μ-CCH)Co2(CO)6}}] (M = Mn, 5; Re, 6), the structures of which have been confirmed by an X-ray determination on a crystal of compound 5.  相似文献   

13.
Photolysis of a hexane solution containing ironpentacarbonyl, 1-ferrocenyl-4-phenyl-1,3-butadiyne at low temperature yields six new products: [Fe(CO)222-PhCCCC(Fc)C(CCPh)C(Fc)Fe(CO)3}-μ-CO] (1), [Fe2(CO)6{μ-η1122-PhCCCC(Fc)-C(O)-C(Fc)CCCPh}] (2), [Fe2(CO)6{μ-η1122-FcCC(CC Ph)-C(O)-C(Fc)CCCPh}] (3), [Fe2(CO)6{μ-η1122-FcCCCC(Fc)-C(O)-C(Fc)CCCPh}] (4), [Fe(CO)3{μ-η2: η2-[FcCC(CCPh)C(CCPh)C(Fc)}CO] (5) and [Fe(CO)3{μ-η2: η2-[FcCC(CCPh)C(CCPh)C(Fc)}CO] (6) formed by coupling of acetylenic moieties with CO insertion on metal carbonyl support. In presence of CO, formation of another new product 2,5-bis(ferrocenyl)-3,6-bis(tetracarbonylphenylmaleoyliron)quinone (7) was observed which on further reaction with ferrocenylacetyene gave the quinone, 2,5-bis(ferrocenyl)-3,6-bis(ethynylphenyl)quinone (8). Structures of 1-5 and 8 were established crystallographically.  相似文献   

14.
Treatments of a bis(diphenylphosphino)methylene (dppm) bridged dicobalt complex, Co2(CO)6(dppm) (4), with propargylamine and 4-ethynylaniline at 25 °C for 24 h gave [(dppm)Co2(CO)4(μ-HCCCH2NH2)] (5) and [(dppm)Co2(CO)4(μ-HCCC6H4NH2)] (6), respectively. Interestingly, only alkynyl amines bridged dicobalt complexes were obtained rather than the previously observed coupling products. The results are in acceptance with the proposed mechanism which describes the formation of the coupling products {[Co2(CO)6(μ-HCC-)]-CH2NH}2CO (1) and {[Co2(CO)6(μ-HCC-)]-C6H4N}2 (2) from the reaction of Co2(CO)8 with propargylamine and 4-ethynylaniline, respectively. Similar results were attained for the reactions of 4 with propioamide and 1-ethynylcyclohexylamine at 25 °C for 24 h which yielded [(dppm)Co2(CO)4(μ-HCCC(O)NH2)] (7) and [(dppm)Co2(CO)4(μ-HCCC6H10NH2)] (8), respectively.Reaction of 1-ethynylcyclohexylamine with one molar equivalent of Co2(CO)8 in THF at 25 °C for 15 min gave an alkyne bridged dicobalt complex, [Co2(CO)6(μ-HCCC6H10NH2)] (9). Direct treatment of 3-ethynlaniline with one molar equivalent of Co2(CO)8 in THF at 25 °C for 1 h gave an alkyne bridged dicobalt complex, [Co2(CO)6(μ-HCCC6H4NH2)] (11) and an azobenzene derivative, {[Co2(CO)6(μ-HCC)]C6H4N}2 (10).Further treatments of 8, 9, and 11 with one molar equivalent of Sanger’s reagent, 2,4-dinitrofluorobenzene, in THF at25 °C for 48 h gave [(dppm)Co2(CO)4(μ-HCCC6H10NHC6H3(NO2)2)] (13), [Co2(CO)6(μ-HCCC6H10NHC6H3(NO2)2)] (14), and [Co2(CO)6(μ-HCCC6H4NHC6H3(NO2)2)] (15), respectively.  相似文献   

15.
You-Chen Hsiao 《Tetrahedron》2008,64(40):9507-9514
Several cobalt-containing P,N-ligands, alkyne-bridged dicobalt phosphines [(μ-PPh2CH2PPh2)Co2(CO)4(μ,η-Me2NCH2CCPR2)] (4a: R=tBu; 4b: R=Ph; 4c: R=Cy), were prepared from the reactions of corresponding alkynylphosphines Me2NCH2CCPR2 (2a: R=tBu; 2b: R=Ph; 2c: R=Cy) with a dppm-bridged dicobalt complex [Co2(CO)6(μ-P,P-PPh2CH2PPh2)] 3. A unique palladium complex ion pair [(μ-PPh2CH2PPh2)Co2(CO)4(μ,η-Me2NCH2CCP (tBu)2)Pd(η3-C3H5)]+[(η3-C3H5)PdCl2]7a was obtained from the reaction of 4a with [(η3-C3H5)PdCl]2. Compounds 4a, 4b, and 4c are authentic cobalt-containing P,N-bidentate ligands and can be used for ligation of palladium from various sources such as Pd(OAc)2 or [(η3-C3H5)PdCl]2. Satisfactory efficiencies were observed for the amination reactions of aryl bromides with morpholine employing either a 4a-chelated palladium complex formed in situ or pre-formed 7a as the catalytic precursor.  相似文献   

16.
2,2′-Bipyrimidine metal complexes with Ti, Mo, Fe, Ru, Pt, Ag, and Cu transition metal atoms have been synthesized and structurally characterized. These molecules were prepared by following synthesis methodologies. The reaction of 2,2′-bipyrimidine (1; bipym) with {[Ti](μ-σ,π-CCSiMe3)2}AgOTf ([Ti] = (η5-C5H4SiMe3)2Ti, OTf = OSO2CF3) (2) in a 1:1 molar ratio gave [{[Ti](μ-σ,π-CCSiMe3)2}Ag(bipym)]OTf (3) which on further treatment with another equivalent of 2 produced [({[Ti](μ-σ,π-CCSiMe3)2}Ag)2(μ-1,2,3,4-bipym)](OTf)2 (4). As consequence thereof, the coordination number of Ag(I) was changed from 3 to 4. A platinum-bipym complex with two acetylide substituents was accessible by the gradual reaction of 1 with K2[PtCl4] (5) and two equivalents of HCCR (7a, R = SiMe3; 7b, R = Fc; 7c, R = Rc; Fc = (η5-C5H4)(η5-C5H5)Fe; Rc = (η5-C5H4)(η5-C5H5)Ru) in di-iso-propylamine and in presence of [CuI]. Originating from cis-[(bipym)Pt(CCR)2] (8a, R = SiMe3; 8b, R = Fc; 8c, R = Rc) diverse multinuclear complexes with two, three or four different transition metals could be obtained. These are: [((CO)4Mo)(μ-1,2,3,4-bipym)Pt(CCFc)2] (10), [(AgClO4)(μ-1,2,3,4-bipym){[Pt(μ-σ,π-CCFc)2]AgOClO3}] (12), [(McCC)2Pt(μ-1,2,3,4-bipym)({[Ti](μ-σ,π-CCSiMe3)2}M)]X (15a, Mc = Fc, M = Cu, X = PF6; 15b, Mc = Rc, M = Cu, X = PF6; 15c, Mc = Fc, M = Ag, X = ClO4), and [(McCC)2Pt(μ-1,2,3,4-bipym)PtCl2] (17). Like other organometallic Pt-Ag tweezer complexes, compound 12 decomposed to give FcCC-CCFc (13). During prolonged stirring of 15a and 15b, respectively, [(McCC)2Pt(μ-1,2,3,4-bipym)({[Ti](μ-σ,π-CCSiMe3)(μ-σ,π-CCH)}M)]X (15′a, M = Cu, X = PF6; 15′b, M = Cu, X = PF6) was formed.The structures of 8b, 8c, 15a′, and 15b′ in the solid state are reported. All complexes exhibit the anticipated planar dinuclear Pt-M structure (M = Pt, Cu, Ag) with the 2,2′-bipyrimidine unit in a μ-1,2,3,4-bridging mode.Electrochemical investigations were carried out with 8a, 8b, and 8c and show that no significant influence of R on the bipym redox potentials exists. The typical redox behavior for the bipym, ferrocene, ruthenocene units and platinum were observed.  相似文献   

17.
Two cobalt-containing bulky monodentate phosphines {[(μ-PPh2CH2PPh2)Co2(CO)4][(μ,η-(tBu)2PCCAr]} (4cm: Ar = 3-CF3C6H4; 4cmm: Ar = 3,5-(CF3)2C6H3) were prepared from the reaction of Co2(CO)6(μ-PPh2CH2PPh2) (3) with each corresponding alkynes (tBu)2PCCAr. Both compounds were converted to their oxidized forms {[(μ-PPh2CH2PPh2)Co2(CO)4][(μ,η-(tBu)2P(O)CCAr]} (4cmO: Ar = 3-CF3C6H3; 4cmmO: Ar = 3,5-(CF3)2C6H3) in the presence of oxide. Further reactions of 4cm and 4cmm with Pd(OAc)2 gave palladium complexes {[(μ-PPh2CH2PPh2)Co2(CO)4][(μ,η-(tBu)2PCC(Ar)-κC1)]Pd(μ-OAc)} 5cm (Ar = 3-CF3C6H3) and 5cmm (Ar = 3,5-(CF3)2C6H2), respectively. By contrast, reactions of 4cm and 4cmm with Pd(COD)Cl2 gave products, [{μ-P,P-PPh2CH2PPh2}Co2(CO)3(μ-CO){μ,η-(tBu)2PCCAr}]-PdCl2] 8cm and 8cmm, respectively, with unique bonding modes. Several crystallines of [(4cm)2Pd3(μ-Cl)(μ-CO)2)(μ-Cl)]2 (9) were obtained along with crystallines of 8cm during the crystallization process. The crystal structures of all three compounds, 4cmmO, 8cmm and 9 were determined by single-crystal X-ray diffraction methods. Fair to excellent efficiencies were observed for employing 4cmm/palladium salt as catalytic precursor in amination as well as in Suzuki coupling reactions.  相似文献   

18.
The synthesis of biferrocene-bridged NCN pincer palladium and platinum complexes (NCN = [1-C6H2(CH2NMe2)2-3,5]) is discussed. Sonogashira cross-coupling of [(η5-C5H4)Fe(η5-C5H4CCH)]2 (1) with I-1-NCN-4-X (2a, X = H; 2b, X = Br) produces [(η5-C5H4)Fe(η5-C5H4CC-1-NCN-4-X)]2 (3a, X = H; 3b, X = Br). Homobimetallic 3b further reacts with [Pd2(dba)3 · CHCl3] (4) or [Pt(tol)2(SEt2)]2 (5) (dba = dibenzylidene acetone, tol = 4-tolyl), respectively, to give tetrametallic [(η5-C5H4)Fe(η5-C5H4CC-4-NCN-1-MBr)]2 (6, M = Pd; 7, M = Pt) in which NCN-MBr fragments are connected by a biferrocene unit. Cyclovoltammetric studies show that the ferrocene moieties can independently be oxidized. The difference of the Fe(II)/Fe(III) redox couples amounts to ca. 300 mV and is not affected by the nature of the NCN pincer metal moities.  相似文献   

19.
Alkyl-carbonyl-iridium [Ir(CH3)(CO)(η2-O2CR′)(PPh3)2]+ (1, R′ = CH3, Ph, p-C6H4CH3) react with alkynes (RCCH; R = Ph, p-C6H4CH3) in the presence of NEt3 to give acyl-alkynyl-iridium Ir(C(O)CH3)(-CCR)(η2-O2CR′)(PPh3)2 (4) which further react with RCCH to give alkyl-carbonyl-cis-bis(alkynyl) iridium Ir(CH3)(CO)(CCR)2(PPh3)2 (5). cis-Bis(alkenyl)iridium complexes, Ir(-CHCH2)22-O2CCH3)(PPh3)2 (6) and (η2-O2CCH3)(PPh3)2 (7) react with substituted alkynes RCCH (R = Ph, p-C6H4CH3, cyclohex-1-enyl) to give cis-bis(alkynyl) Ir(CCR)22-O2CCH3)(PPh3)2 (9) that further react with RCCH to undergo the alkyne insertion reaction into the Ir-O bond to produce iridacycles containing vinyl acetate ligands, (-CCR)2(PPh3)2 (8).  相似文献   

20.
The multifunctional ligands [(Z)-FcCCSC(H)C(H)XR] [X = O, R = Me (2a); X = O, R = Et (2b); X = S, R = Ph (3); X = S, R = C6F5 (5)] and [(Z,Z)-Fc(SR)CC(H)SC(H)C(H)SR] [R = Ph (4), C6F5 (6)] have been prepared through hydroalkoxylation and hydrothiolation processes of the alkyne groups in the compound FcCCSCCH 1. Reactions between compound 3 and the carbonyl metals Co2(CO)8, Os3(CO)10(NCMe)2 and Fe2(CO)9 have allowed the synthesis of the polynuclear compounds [(Z)-{Co2(CO)6}(μ-η2-FcCCSC(H)C(H)SPh)] 9, [(Z)-Os3(CO)9(μ-CO){μ32-FcCCSC(H)C(H)(SPh)}] 10 and [(Z)-{Fe3(CO)9}[μ33-(CCS)-FcCCSC(H)C(H)(SPh)] 11. All the compounds have been characterized by elemental analysis, 1H and 13C{1H} NMR spectroscopy, mass spectrometry and the crystal structure of compounds [(Z)-FcCCSC(H)C(H)OMe] 2a and [{Co2(CO)6}2(μ-η22-FcCCSCCSiMe3)] 7 have been solved by X ray diffraction analysis.  相似文献   

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