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1.
Preparations by the high dilution method are reported for seven macrocyclic thioether-esters and thioether-thioesters (L1–;L7). Yields in these reactions between thiodiglycolyl dichloride and appropriate ,ω-diols or dithiols range from 10 to 51%. The compounds are characterized by 1H and 13C NMR, IR and high resolution mass spectroscopy. They react with salts of Pd(II), Pt(II) and Ag(I) to form complexes of which MX2·L2, (M = Pt, X = Cl; M = Pd, X = Cl, Br, I, SCN), [Pd(L2)2][CF3SO3]2·H2O and [Ag(L5)2][CF3SO3]·C2H5OH have been isolated and characterized by elemental analysis, IR and NMR spectroscopy. NMR spectra indicate reversible dissociation of the ligand occurs in dimethyl sulfoxide solvent for PdCl2·L2 but not for the Pt analogue. For PtCl2·L2, spectra indicate that the ligand is undergoing a conformational ‘wag’ about its pair of equivalent sulfurs. These remain bound to the metal while the unique sulfur moves from the apical position of the coordination sphere to a non-coordinated situation. Simultaneously, inversions at the bound sulfurs are occurring.  相似文献   

2.
A series of polymer- and silica-supported manganese phosphine complexes has been prepared and characterized. These complexes react reversibly with molecular oxygen in the solid state to yield 1:1 Mn:O2 adducts. The reaction may be reversed either by a pressure drop or a temperature rise. All the O2 adducts are highly colored and binding curves as a function of the partial pressure of oxygen have been constructed. The silica-supported complexes can be prepared from ligand-silanes either by reaction with dehydrated silica and then with anhydrous manganese(II) bromide or vice versa.  相似文献   

3.
By reacting [(C5Me5)M(SRF)2] (forM = Ir, Rf = C6F5 (1a) or C6F4H-p (1b); for M = Rh, Rf = C6F5 (2a) or C6F4H-p (2a)) in toluene with Na[AuCl4], ionic binuclear compounds with the general formula [(C5Me5)M(μ-SRF)2AuCl2]Cl for M = Ir, R = C6F5 (3a) or C6F4H-p (3a); for M = Rh, RF = C6F5 (4a) or C6F4H-p (4b) can be obtained, together with small amounts of [(C5Me5)2Rh2(μ-SRF)(μ-Cl)2]Cl (RF = C6F5 (5a) or C6F4H-p (5b)) as by-products when 2a and 2b were used.  相似文献   

4.
Treatment of MHCl(CO)(PPh3)3 (M=Ru, Os) with (CH2=CH)SnR3 is a good general route to the coordinatively unsaturated osmium and ruthenium stannyl complexes M(SnR3)Cl(CO)(PPh3)2 (1: M=Ru, R=Me; 2: M=Ru, R = n-butyl; 3: M=Ru, R = p-tolyl; 4: M=Os, R=Me). These coordinatively unsaturated complexes readily add CO and CN-p-tolyl to form the coordinatively saturated compounds M(SnR3)Cl(CO)L(PPh3)2 (5: M=Ru, R=Me, L=CO; 6: M=;Ru, R = n-butyl, L=CO; 7: M=Ru, R = p-tolyl, L=CO; 8: M=Os, R=Me, L=CO; 9: M=Ru, R=Me, L=CN-p-tolyl; 10: M=Ru, R = n-butyl, L=CN-p-tolyl; 11: M=Os, R=Me, L=CN-p-tolyl). In addition, the chloride ligand in Ru(SnR3)Cl(CO)(PPh3)2 proves to be labile and treatment with the potentially bidentate anionic ligands, dimethyldithiocarbamate or diethyldithiocarbamate, affords the coordinatively saturated compounds Ru(SnR3)(η2-S2CNR′2)(CO)(PPh3)2 (12: R=Me, R′ = Me; 13: R=Me, R′ = Et; 14: R = n-butyl, R′ = Me; 15: R = p-tolyl, R′ = Me; 16: R = p-tolyl, R′ = Et). Chloride is also displaced by carboxylates forming the six-coordinate compounds Ru(SnR3)(η2-O2CR′)(CO)(PPh3)2 (17: R=Me, R′ = H; 18: R=Me, R′ = Me; 19: R=Me, R′ = Ph; 20: R = n-butyl, R′ = Me; 21: R = p-tolyl, R′ = Me). IR and 1H NMR spectral data for all the new compounds and 31P and 119Sn NMR spectral data for selected compounds are reported.  相似文献   

5.
The synthesis of new β-diketonato rhodium(I) complexes of the type [Rh(FcCOCHCOR)(CO)2] and [Rh(FcCOCHCOR)(CO)(PPh3)] with Fc=ferrocenyl and R=Fc, C6H5, CH3 and CF3 are described. 1H, 13C and 31P NMR data showed that for each of the non-symmetric β-diketonato mono-carbonyl rhodium(I) complexes, two isomers exist in solution. The equilibrium constant, Kc, which relates these two isomers in an equilibrium reaction, are concentration independent but temperature and solvent dependent. ΔrG, ΔrH and ΔrS values for this equilibrium have been determined and a linear relationship between solvent polarity on the Dimroth scale and Kc exists. The relationship between RhP bond lengths, d(RhP), and 31P NMR peak positions as well as coupling constants 1J(31P103Rh) has been quantified to allow calculation of approximate d(RhP) values. Variations in d(RhP) for [Rh(RCOCHCOR′)(CO)(PPh3)] complexes have also been related to the group electronegativities (Gordy scale) of the terminal β-diketonato R groups trans to PPh3. A measure of the electron density on the rhodium centre of [Rh(RCOCHCOR′)(CO)(PPh3)] may be expressed in terms of the IR carbonyl stretching wave number, ν(CO), the sum of the group electronegativities of the R and R′ groups, (χR+χR′), or the observed pKa values of the free β-diketones RCOCH2COR. An empirical relationship between ν(CO) and either pKa or (χR+χR′) has also been quantified.  相似文献   

6.
The hydroxo complex [NBu4]2[Ni2(C6F5)4(μ-OH)2] reacts with ammonium O,O-dialkyldithiophosphates, O-alkyl-p-methoxyphenyldithiophosphonate acids and ammonium O-alkylferrocenyldithiophosphonates in dichloromethane under mild conditions to give, respectively, [NBu4][Ni(C6F5)2{S(S)P(OR)2}] (R=Me (1), Et (2), iPr (3)) and [NBu4][Ni(C6F5)2{S(S)P(OR)Ar}] (Ar=p-MeOC6H4, R=Me (4), Et (5), iPr (6); Ar=ferrocenyl; R=Me (7), Et (8), iPr (9)). The monothiophosphonate nickel complexes [NBu4][Ni(C6F5)2{S(S)P(OR)(ferrocenyl)}] (R=Et (10), iPr (11)) are obtained by reaction of the hydroxo complex with O-alkylferrocenyldithiophosphonate acids. Analytical (C, H, N, S), conductivity, and spectroscopic (IR, 1H, 19F and 31P NMR, and FAB-MS) data were used for structural assignments. A single-crystal X-ray diffraction study of [NBu4][Ni(C6F5)2{S(S)P(OMe)(p-MeOC6H4)}] (4) and [NBu4][Ni(C6F5)2{S(O)P(OEt)(ferrocenyl)}] (10) shows that in both cases the coordination around the nickel atom es essentially square planar with NiC2S2 and NiC2SO central cores, respectively.  相似文献   

7.
A spectroscopic and spectroelectrochemical comparison is made among homo- and heterobimetallic complexes of the form [(bpy)2Ru(BL)Os(byp)2]4+, [(bpy)2Ru(BL)Ru(bpy)2]4+ and [(bpy)2Os(BL)Os(bpy)2]4+ (BL = 2,3,-bis(2′-pyridyl)pyrazzine(dpp),2,3-bis(2′-pyridyl)quinoxaline(dpq) or 2,3-bis(2′-pyridyl)benzoquinoxaline(dpb); bpy = 2,2′-bipyridine). It has been postulated that the spectroscopy of the mixed-metal bimetallic complexes bridged by polyazine bridging ligands can be assigned by comparison to those of the homobimetallic analogs. We have in hand a unique series of complexes where such a postulate can be tested. Utilizing the visible spectra of the homobimetallic Os,Os and Ru,Ru systems, we have been able to generate the spectra of the mixed-metal complexes. Some differences have been seen, particularly in the energy of the Os → dpp 3MLCT. Oxidative spectroelectrochemistry studies on the homobimetallic ruthenium or osmium based systems indicate that upon complete oxidation of both metal centers, transitions in the visible are lost. Hence, partial oxidation of the ruthenium based homobimetallics and Os, Ru mixed-metal bimetallics allows for the direct comparison of the spectroscopic character of the one remaining ruthenium chromophore within these mixed-valence systems. Oxidation to form the Os(III)/Ru(II) species and the Ru(III)/Ru(II) species resulted in similar spectra. This establishes further that the visible spectroscopy of mixed-metal systems of this nature can be accurately interpreted by comparison to the homobimetallic analogs.  相似文献   

8.
The potential in preparative chemistry of the precursors trans-[Ru(NH3)(CC---R1)(Ph2PCH2CH2PPh2)2]PF6 (3) has been studied. They offer a convenient access, by NH3 displacement, to new functional alkynyl-ruthenium derivatives. Complexes 3 react with alkynes HCC---R2 to give unsymmetrical trans-Ru(---CC---R1)(---CC---R2)(dppe)2 compounds 4a-c, and with sodium methoxide in methanol they open the route to a variety of mixed hydride complexes 5a-c, trans-Ru(H)(---CC---R1)(dppe)2. In contrast, with carbon monoxide or isocyanides CN---R3 (R3:CH2Ph, C6H11, Me3C) they allow the preparation of cationic derivatives trans-(Ru(CO)(---CC---R1)(dppe)2]PF6 (6a-c) or trans-[Ru(CNR3)(---CC---R1)(dppe)2]PF6 (7a-d).  相似文献   

9.
Copper(II), nickel(II) and cobalt(II) complexes of the aspirin metabolite salicylglycine (H2L), of stoichiometry M(HL)2·solvate, have been prepared and characterised. In these complexes salicylglycinate is coordinated to the metal via its carboxylato group and possibly also its amide oxygen in the copper(II) complex. Under basic conditions copper(II) forms the complex Cu(LH−1)·2H2O·MeOH, in which the ligand is coordinated to the metal via its carboxylate and phenolate oxygen atoms and the deprotonated peptide nitrogen atom.  相似文献   

10.
A series of Iron (Fe(II)) and manganese (Mn(II)) complexes of 1,3-substituted 5-(2-benzothiazolyl)formazans are reported. The crystal structures of the Fe(II) and Mn(II) complexes of 1,3-diphenyl-5-(2-benzothiazolyl)formazan are very similar and both contain a coordination sphere of four five-membered rings involving the N1 and N3 nitrogen atoms of the formazan chain and the N2 of the heterocyle resulting in a distorted octahedral structure in both cases. The distortions arise primarily from the spatial requirements of the bulky phenyl substituents.  相似文献   

11.
After reaction with alkyl iodides and subsequent oxidative removal of the M(CO)3 triprotection, molybdenum and chromium fac-LM(CO)3 complexes of cyclen (L) unexpectedly lead to N1,N7-dialkylated cyclen derivatives.  相似文献   

12.
The bimetallic cyclosiloxanolate cluster complexes Na[PhSiO2)6Cu4Ni26-Cl)(PhSiO2)6] (1) and Na[(PhSiO2)6Cu3Ni3(μ6-Cl)(PhSiO2)6] (2) were prepared by Na+ and Ni2+ ion exchange from in situ generated Na2 {[(PhSiO2)6]2Na4Ni4(OH)2}. Complexes 1 and 2 were characterized by analytical, spectroscopic and electrochemical methods as well as complex 2 by single-crystal X-ray diffraction. The X-ray structure shows a sandwich-type array comprising two superimposed cyclosiloxanolate rings and an M6Cl unit in between. For the first time the regioselectivity of the metal ion exchange could be deduced from the X-ray structural parameters.  相似文献   

13.
Protonation of Na3[Ta(CO)5] in liquid ammonia provides the thermally unstable Na[Ta(CO)5NH3], which may be isolated as the crystalline and deep violet salt [Ph4As][Ta(CO)5NH3]. Sodium amminepentacarbonyltantalate(1−) reacts with PMe3, PPh3, P(OMe)3, AsPh3, SbPh3, CNtBu and CN at about 0°C in NH3/THF to give exclusively the corresponding [Ta(CO)5L]z. These have been isolated as tetraethylammonium salts in 54–84% yields.  相似文献   

14.
The dimetal μ-vinylidene complexes Cp(CO)2MnPt(μ-C = CHPh)L2 (L = tert.-phosphine or -phosphite), which have been obtained by coupling of the mononuclear complex Cp(CO)2Mn=C=CHPh and unsaturated PtL2 unit, add smoothly the Fe(CO)4 moiety to produce trimetal MnFePt compounds. The μ3-vinylidene cluster CpMnFePt(μ3-C=CHPh)(CO)6(PPh3) was prepared in quantitative yields from the reactions of Cp(CO)2MnPt(μ-C=CHPh)(PPh3)L (L = PPh3 or CO) with Fe2(CO)9 in benzene at 20 °C. The phosphite-substituted complexes Cp(CO)2Mnpt(μ-C=CHPh)L2 (L = P(OEt)3 or P(OPri)3) react under analogous conditions with Fe2(CO)9 to give mixtures (2:3) of the penta- and hexacarbonyl clusters, CpMnFePt(μ3-C = CHPh)(CO)5L2 and CpMnFePt(μ3-C = CHPh)(CO)6L, respectively. The similar reaction of the dimetal complex Cp(CO)2MnPt(μ-C = CHPh)(dppm), in which the Pt atom is chelated by dppm = Ph2PCH2PPhPin2 ligand, gives only a 15% yield of the analogous trimetal μ3-vinylidene hexacarbonyl product CpMnFePt(μ3-C = CHPh)(CO)(dppm), but the major product (40%) is the tetranuclear μ4-vinylidene cluster (dppm)PtFe34-C = CHPh)(CO)9. The IR and 1H, 13C and 31P NMR data for the new complexes are reported and discussed.  相似文献   

15.
A number of gallium(III) organophosphonates form adducts with the bidentate amines 2,2′-bipyridyl and 1,10-phenanthroline. These adducts contain a 1:2:1 molar ratio of metal/phosphorus/amine and have the proposed formulations Ga(O3PR)(O2P(OH)R)(C10H8N2)·H2O and Ga(O3PR)(O2P(OH)R)(C12H8N2)·H2O (where R=CH3, C6H5 and CH2C6H5; C10H8N2 is 2,2′-bipyridyl and C12H8N2 is 1,10-phenanthroline). Unlike the parent gallium(III) organophosphonates, which conform to the general formula Ga(OH)(O3PR)·xH2O (x=0 or 1), the amine adducts lack the hydroxo group, but contain the organophosphonate ligand in the partially as well as fully deprotonated forms. All compounds were isolated from aqueous solutions as monohydrates, with the exception of the bipyridyl adduct of gallium(III) phenylphosphonate, which is anhydrous. TGA measurements suggest that for the hydrates, the water molecule is not coordinated to the metal. The bipyridyl adducts of gallium(III) phenylphosphonate and gallium(III) methylphosphonate, like the parent gallium(III) organophosphonates, are very likely layered, as indicated by the powder XRD patterns. In contrast, the corresponding phenanthroline adducts are non-layered, and both the bipyridyl and phenanthroline adducts of gallium(III) benzylphosphonate are amorphous solids. FTIR, powder XRD, TGA, XPS, solid state 31P/13C MAS-NMR and BET surface area data are presented and discussed.  相似文献   

16.
Addition of (Cp*2YH)2 (4) to 2-methyl-1,4-pentadiene produced the yttrium-alkyl-alkene chelate complex Cp*2YCH2CH2CH2C(CH3)=CH2 (2) in which a disubstituted alkene is complexed to the metal center. Evidence for coordination of the alkene unit of 2 comes from the 1H and 13C NMR chemical shifts of the vinyl units and from observation of nOe effects between Cp* protons and vinyl hydrogens. The disubstituted alkene ligand of 2 is weakly bound, and evidence for an equilibrium with substantial amounts of complex 3 with a free alkene was obtained from variable temperature 1H NMR spectroscopy.  相似文献   

17.
The reversible equilibrium conversion under H2 of [RuCl(dppb) (μ-Cl)]2 (1) to generate (η2-H2) (dppb) (μ-Cl)3RuCl(dppb) in CH2Cl2 (dppb = Ph2P(CH2)4PPh2) has been studied at 0–25 °C by UV-Vis and 31P{1H} NMR spectroscopy, and by stoppe kinetics; the equilibrium constant and corresponding thermodynamic parameters, and the forward and reverse rate constants at 25 °C have been determined. A measured ΔH° value of 0 kJ mol−1 allows for an estimation of an exothermicity of 60 kJ mol−1 for binding an η2-H2 at an Ru(II) centre; a ΔS° value of 60 J mol−1 K−1 indicates that in solution 1 contain s coordinated CH2Cl2. The kinetic and thermodynamic data are compared to those obtained from a previously studied hydrogenation of styrene catalyzed by 1. Preliminary findings on related systems containing Ph2P(CH2)3PPh2 and (C6H11)2P(C6H11)2 are also noted.  相似文献   

18.
The hetero-bimetallic Ind complexes (Ind=indenyl anion) with the formula (CO)3Cr(μ-Ind)RhL2 (L=CO, ethylene; L2=COD, COT, NBD) have two possible conformers, one with the metals at antipodal sides of the condensed bicyclic polyene (antarafacial, anti) and the other with both metals on the same side (cofacial, syn). These systems can be considered to contain 34 valence electrons by assuming that Ind is capable of donating all of its ten π electrons to the metals. A qualitative MO analysis, based on EHMO calculations, is presented. The anti conformer is compared to the homometallic 34e species, namely [CpRu(μ-Ind)RuCp]+. Here, the pseudo-symmetrical relationship between the two identical metal fragments strongly suggests that one Ind σ-bonding MO donates part of its electron density to each of the two metals, which thus become formally saturated (36e). This argument is extended to the anti Cr---Rh derivative in which a critical role is played by an empty FMO of the (CO)2Rh(I) fragment with π symmetry (i.e. lying in the molecular mirror plane). The latter, in spit the large πCO* contributions, has good acceptor capabilities at the metal.The calculations suggest that the so-called indenyl effect, namely the increased rate of substitution of one CO ligand by another σ donor (e.g. a phosphine), although a structurally dynamic process, also depends on the electron density which accumulates on the aforementioned π FMO. In the series (η5-C5H5)Rh(CO)2, (η5-C7H9Rh(CO)2 and {η5-[(CO)3CrC7H9]}-Rh(CO)2 the progressively reduced donor capabilities of the cyclic polyene toward the (CO)2Rh(I) fragment induce a larger electrophilicity in rhodium, in good agreement with the experimental data on substitution reactivity. Finally, the electronic features of the cofacial conformer (CO)3Cr(μ-Ind)Rh(CO)2 are examined. In spite of the long Cr---Rh separation (> 3 Å) the graphically illustrated MO analysis indicates a direct, heterodox, intermetallic linkage, which helps the metals to achieve a formal electronic saturation. In this case, the limited propensity of the complex toward any CO substitution reactions is likely attributable to the hindered mobility of the (CO)2Rh(I) fragment.  相似文献   

19.
The pKa values of curcumin and diacetylcurcumin are, here doubtless, determined by means of spectroscopic and potentiometric measurements, and the enolic proton is the more acidic one. The interaction of Fe3+ with curcumin and diacetylcurcumin, in water/methanol 1:1 solution, leads to the formation of the complex species [FeH2CU(OH)2] and [FeDCU(OH)2] (H2CU and DCU=curcumin or diacetylcurcumin monoanion, respectively) which prevails near pH 7. At more basic condition the prevailing species are [FeH2CU(OH)3] and [FeDCU(OH)3], which prevent metal hydroxide precipitation. 1H NMR data state that the dissociated β-diketo moiety of the ligands is involved in metal chelation. The pKa value of the deprotonation reaction is strongly anticipated by the metal ion, as shown by UV spectral data. The stability constants, evaluated from potentiometric data, are near to that of desferrioxamine, which is, by now, the only iron-chelating agent for clinical use.  相似文献   

20.
Treatment of the A-ring aromatic steroids estrone 3-methyl ether and β-estradiol 3, 17-dimethyl ether with Mn(CO)5+BF4 in CH2Cl2 yields the corresponding [(steroid)Mn(CO)3]BF4 salts 1 and 2 as mixtures of and β isomers. The X-ray structure of [(estrone 3-methyl ether)Mn(CO)3]BF4 · CH2Cl2 (1) having the Mn(CO)3 moiety on the side of the steroid is reported: space group P21 with a=10.3958(9), b=10.9020(6), c=12.6848(9) Å, β=111.857(6)°, Z=2, V=1334.3(2) Å3, calc=.481 cm−3, R=0.0508, and wR=0.0635. The molecule has the traditional ‘piano stool’ structure with a planar arene ring and linear Mn---C---O linkages. The nucleophiles NaBH4 and LiCH2C(O)CMe3 add to [(β-estradiol 3,17-dimethyl ether)Mn(CO)3]BF4 (2) in high yield to give the corresponding - and β-cyclohexadienyl manganese tricarbonyl complexes (3). The nucleophiles add meta to the arene -OMe substituent and exo to the metal. The and β isomers of 3 were separated by fractional crystallization and the X-ray structure of the β isomer with an exo-CH2C(O)CMe3 substituent is reported (complex 4): space group P212121 with a=7.5154(8), b=15.160(2), c=25.230(3) Å, Z=4, V=2874.4(5) Å3, calc=1.244 g cm−3, R=0.0529 and wR2=0.1176. The molecule 4 has a planar set of dienyl carbon atoms with the saturated C(1) carbon being 0.592 Å out of the plane away from the metal. The results suggest that the manganese-mediated functionalization of aromatic steroids is a viable synthetic procedure with a range of nucleophiles of varying strengths.  相似文献   

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