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1.
Reaction of L {L = [24]aneS 8, [28]aneS 8} with two molar equivalents of [Cu(NCMe) 4]X (X − = ClO 4−, BF 4−, PF 6−) in MeCN affords the white binuclear copper(I) complexes [Cu 2(L)] 2+. A single crystal X-ray structure determination of [CU 2([24]aneS 8)](BF 4) 2 shows two tetrahedral copper(I) centres, each of which is coordinated to four thioether sulphur-donors, Cu---S(1) = 2.263(3), Cu---S(4) = 2.363(3), Cu---S(7) = 2.349(3), Cu---S(10) = 2.261(3) Å. The Cu … Cu distance is 5.172(3) Å. A single crystal X-ray structure determination Of [CU 2([28]aneS 8)](ClO 4) 2 shows that this complex also contain two tetrahedral copper(I) centres, each coordinated to four thioether sulphur-donors, Cu---S(1) = 2.278(5), Cu---S(4) = 2.333(5), Cu---S(8) = 2.328(5), CU---S(11) = 2.268(5) Å. The Cu … Cu distance of 6.454(3) Å is greater than in [CU 2([24]aneS 8)] 2+ , reflecting the greater cavity size in [CU 2([28]aneS 8)] 2+. Cyclic voltammetry of [CU 2([24]aneS 8)] 2+ and [CU 2([28]aneS 8)] 2+ at platinum electrodes in MeCN (0.1 M nBU 4NPF 6) shows irreversible oxidations at Epa, = +0.88 V, +0.92 V vs Fc/Fc +, respectively, at a scan rate of 200 mV s −1. Coulometric measurements in MeCN confirm these oxidations to be two-electron (one electron per copper) processes to give binuclear copper(II) species. Oxidation of the binuclear copper(I) precursors with H 2SO 4 or HNO 3 affords ESR-active copper(II) species which presumably incorporate SO 42− and NO 3− bridges. 相似文献
2.
Both ionic [HgR(DMSO)][CF 3SO 3] (R = Me or Ph) and covalent HgMeI organomercury(II) compounds react with the tripodal ligand N(CH 2CH 2PPh 2) 3 (np 3) to yield as ultimate products Hg(II) complexes, the new five-coordinated [Hg(OSO 2CF 3)(np 3)] + or the known tetrahedral [HgI(np 3)] + and symmetric diorganomercurials respectively. Monitoring of the reactions by 1H, 31P and 13C NMR spectroscopy has shown that the mechanistic pathways depend on the nature of the reagents. 相似文献
3.
The crystal and molecular structures of two quarternary salts of 2-oxosparteine (II), the methiodide (IICH +3 • I −) and the methperchlorate (IICH +3 • ClO −4) have been determined on the basis of X-ray and IR data. The studies were performed by analogy to previously investigated quaternary salts of sparteine (I), the methiodide (ICH +3 • I −) and the methperchlorate (ICH +3 • ClO −4). As expected, the configurations and conformations of cationic parts within the two pairs of quaternary salts are identical, except for the structure of their A/B fragments, which in ICH +3 cations have the character of tertiary amines, but in IICH +3 that of lactams. On the basis of accumulated X-ray and IR data the similarities and differences in the modes of interaction of perchlorate and iodide anions with quaternary cations, and especially with their N+---CH3 groups are discussed. In this discussion are also included the methiodide and methperchlorate of -isosparteine: IIICH+3 • X− (X− = I− or ClO−4) where N+---CH3 groups are cisoidally oriented to the basic nitrogen atoms. The most interesting observations are as follows: (i) When N+---CH3 groups are easily accessible for direct quasi hydrogen bonding interactions with counter anions and when other positive charged groups, for instance lactam groups, are absent in quaternary cations, perchlorate anions interact more strongly than the iodide anions and in consequence introduce conformational changes into the ring with N+---CH3 group as well as into further rings. (ii) Perchlorate and iodide anions interact with N+---CH3 groups similarly and very weakly if at all, when the N+---CH3 groups are for steric reasons inaccessible to counter anions or when in quaternary cations there are additional groups which attract the counter anions electrostatically. The last mechanism operates in both quaternary salts of 2-oxosparteine and this is the reason why their monocrystals are isosteric and IR spectra almost identical. (iii) The sterically hindered N+---CD3 groups in both IIICD+3 • X− salts give rise in their IR spectra to two doubles of sharp, well resolved bands which indicate the presence of two different rotamers stabilized by two modes of weak intramolecular hydrogen bonds with basic N atoms. (iv) In IIICH+3 • X− and IIICD+3 • X− salts the perchlorate and iodide anions do not interact at all with the rotating and vibrating N+---CH3 (N+---CD3) group but the structures of these salts are not isosteric since the perchlorate anions interact more strongly than iodide anions with the A/B fragment of the IIICH+3 cations. This is visible from the shapes and intensities of the so-called “trans” band in the IR spectra of both salts. 相似文献
4.
The reaction of the anionic mononuclear rhodium complex [Rh(C 6F 5) 3Cl(Hpz)] t- (Hpz = pyrazole, C 3H 4N 2) with methoxo or acetylacetonate complexes of Rh or Ir led to the heterodinuclear anionic compounds [(C 6F 5) 3Rh(μ-Cl)(μ-pz)M(L 2)] [M = Rh, L 2 = cyclo-octa-1,5-diene, COD (1), tetrafluorobenzobarrelene, TFB (2) or (CO) 2 (4); M = Ir, L 2 = COD (3)]. The complex [Rh(C 6F 5) 3(Hbim)] − (5) has been prepared by treating [Rh(C 6F 5) 3(acac)] − with H 2bim (acac = acetylacetonate; H 2bim = 2,2′-biimidazole). Complex 5 also reacts with Rh or Ir methoxo, or with Pd acetylacetonate, complexes affording the heterodinuclear complexes [(C 6F 5) 3Rh(μ-bim)M(L 2)] − [M = Rh, L 2 = COD (6) or TFB (7); M = Ir, L 2 = COD (8); M = Pd, L 2 = η 3-C 3H 5 (9)]. With [Rh(acac)(CO) 2], complex 5 yields the tetranuclear complex [{(C 6F 5) 3Rh(μ-bim)Rh(CO) 2} 2] 2−. Homodinuclear Rh III derivatives [{Rh(C 6F 5) 3} 2(μ-L) 2] ·- [L 2 = OH, pz (11); OH, S tBu (12); OH, SPh (13); bim (14)] have been obtained by substitution of one or both hydroxo groups of the dianion [{Rh(C 6F 5) 3(μ-OH)} 2] 2− by the corresponding ligands. The reaction of [Rh(C 6F 5) 3(Et 2O) x] with [PdX 2(COD)] produces neutral heterodinuclear compounds [(C 6F 5) 3Rh(μ-X) 2Pd(COD)] [X = Cl (15); Br (16)]. The anionic complexes 1–14 have been isolated as the benzyltriphenylphosphonium (PBzPh 3+) salts. 相似文献
5.
The crystal structures of propionaldehyde complex ( RS, SR)-(η 5-C 5H 5)Re(NO)(PPh 3)(η 2-O=CHCH 2CH 3)] + PF 6− (1b + PF 6s−; monoclinic, P2 1/ c (No. 14), a = 10.166 (1) Å, b = 18.316(1) Å, c = 14.872(2) Å, β = 100.51(1)°, Z = 4) and butyraldehyde complex ( RS, SR)-[(η 5-C 5H 5)Re(NO)(PPh 3)(η 2-O=CHCH 2CH 2CH 3)] + PF 6− (1c +PF 6−; monoclinic, P2 1/ a (No. 14), a = 14.851(1) Å, b = 18.623(3) Å, c = 10.026(2) Å, β = 102.95(1)°, Z = 4) have been determined at 22°C and −125°C, respectively. These exhibit C
O bond lengths (1.35(1), 1.338(5) Å) that are intermediate between those of propionaldehyde (1.209(4) Å) and 1-propanol (1.41 Å). Other geometric features are analyzed. Reaction of [(η 5-C 5H 5)Re(NO)(PPh 3)(ClCH 2Cl)] + BF 4− and pivalaldehyde gives [(η 5-C 5H 5)Re(NO)(PPh 3)(η 2-O=CHC(CH 3) 3)] +BF 4− (81%), the spectroscopic properties of which establish a π C
O binding mode. 相似文献
6.
Recent results (post-1990) on the synthesis and structures of bis(trimethylsilyl)methyls M(CHR 2) m (R = SiMe 3) of metals and metalloids M are described, including those of the crystalline lipophilic [Na(μ-CHR 2)] ∞, [Rb(μ-CHR 2)(PMDETA)] 2, K 4(CHR 2) 4(PMDETA) 2, [Mg(CHR 2)(μ-CHR 2)] ∞, P(CHR 2) 2 (gaseous) and P 2(CHR 2) 4, [Yb(CHR 2) 2(OEt 2) 2] and [{Yb(CR 3)(μ-OEt)(OEt 2)} 2]; earlier information on other M(CHR 2) m complexes and some of their adducts is tabulated. Treatment of M(CHR 2) (M = Li or K) with four different nitriles gave the X-ray-characterized azaallyls or β-diketinimates
,
and
(LL′ = N(R)C( tBu)CHR, L′L′ = N(R)C(Ph)C(H)C(Ph)NR, LL″ = N(R)C(Ph)NC(H)C(Ph)CHR, R = SiMe 3 and Ar = C 6H 3Me 2-2,5). The two lithium reagents were convenient sources of other metal azaallyls or β-diketinimates, including those of K, Co(II), Zr(IV), Sn(IV), Yb(II), Hf(IV) and U(VI)/U(III). Complexes having one or more of the bulky ligands [LL′] −, [L′L′] −, [LL] −, [LL″] −, [L″L] −, [LL] − and [{N(R)C( tBu)CH} 2C 6H 4-2] 2− are described and characterized (LL = N(H)C(Ph)C(H)C(Ph)NH, L″L = N(R)C( tBu)C(H)C(Ph)NR, LL = N(R)C( tBu)CHPh). Among the features of interest are (i) the contrasting tetrahedral or square-planar geometry for
and
, respectively, and (ii) olefin-polymerization catalytic activity of some of the zirconium(IV) chlorides. 相似文献
7.
The title compounds react with unidentate ligands, L, containing either phosphorus or arsenic donor atoms to yield the corresponding compounds of the type Ru(η 5---C 5Me 4Et)(CO)LX; with didentate phosphorus donor ligands the major species formed is the bridged complex {Ru(η 5---C 5Me 4Et)(CO)X} 2{Ph 2P(CH 2) nPPh 2} n = 1, X = Br; n = 2, X = Cl). In contrast, unidentate ligands containing nitrogen donor atoms such as pyridine did not react with Ru(η 5---C 5Me 4Et)(CO) 2Cl although reaction with 1,10-phenanthroline or diethylenetriamine yielded the ionic products [Ru(η 5---C 5Me 4Et)(CO)L] +Cl − (L = phen or (NH 2CH 2CH 2) 2NH). Reaction of Ru(η 5---C 5Me 4Et)(CO) 2Br with AgOAc yielded the corresponding acetato complex Ru(η 5---C 5Me 4Et)(CO) 20Ac. Ru(η 5--- C 5Me 4Et)(CO) 2X reacts with AgY (Y = BF 4 or PF 6) in either acetone or dichloromethane to give the useful solvent intermediates [Ru(η 5---C 5Me 4Et)(CO) 2(solvent)] +Y −, which readily react with ligands L to yield ionic derivatives of the type [Ru(η 5---C 5Me 4Et)(CO) 2L] +Y − (where L = CO, NCMe, py, C 2H 4 or MeO 2CCCCO 2Me). 相似文献
8.
Reduction of cyclo-( t-Bu 4Sb 4) (1) with sodium or potassium in boiling tetrahydrofuran leads to the anions [ t-Bu 4Sb 3] − and [ t-Bu 3Sb 2] −. Crystallization with pentamethyldiethylenetriamine (L) gives [M(L) n( t-Bu 4Sb 3)] ( n=1, M=Na (2), K (3); n=2, M=K (4)) and [K(L)( t-Bu 3Sb 2)] (5). Crystal structure analyses reveal coordination of the anionic antimony ligands on the alkali metal ions for 2, 3, and 5. In contrast, no Sb---K interactions were observed in the structure of 4. 相似文献
9.
The one-pot reaction between the novel proton transfer compound (pydaH 2) 2+(phendc) 2−, LH 2, and Cu(II) afforded the compounds (pydaH) 2[Cu(phendc) 2]·10H 2O, 1, and (pydaH) 2[Cu(phendc)(phendcH)] 2·5H 2O, 2, where pyda=2,6-diaminopyridine, and phendcH 2=1,10-phenanthroline-2,9-dicarboxylic acid. The single crystal X-ray diffraction analysis of 1 and 2 revealed that these are two novel self-assembled 3D Cu(II) complex-organo-networks, in which (pydaH) + ions and [Cu(phendc) 2] 2− or complex units are held together by ion pairing, H-bonding, and π–π interactions. Magnetic measurements over the temperature range 1.8–310 K revealed no significant magnetic coupling between Cu(II) centers in 1 or 2. 相似文献
10.
Two types of Co(III) tetraphenylporphyrins, Co(III)TPPX (I) and Co(III)(N)TPPX (II), where X = C1 − or NO −2 and N = C5H5N or C 6H 5CH 2C 5H 4N, are used as ionophores to prepare nitrite responsive polymeric membrane electrodes. The influence of the initial axial ligand (X − and N) on the operative ionophore mechanism of these metalloporphyrins within the solvent polymeric membranes is examined. Results from potentiometric and electrodialysis experiments suggest that in the presence of nitrite in the test sample and internal solution, both types of Co (III) porphyrins studied (I and II) act as neutral carriers and that the addition of lipophilic cationic sites (e.g., tridodecylmethylammonium ions (TDMA +)) to the organic membrane is essential to improve the selectivity and long term stability of sensors prepared with these species. Membranes formulated with (I) or (II) in the nitrite form along with TDMACl in plasticized PVC films exhibit the following selectivity sequence: SCN − > NO −2 ˜ C1O −4 > Sal − > NO −3 > Br − > C1 −. Membrane electrodes with added lipophilic cationic sites are shown to exhibit rapid, fully reversible and Nernstian response towards nitrite ions in the concentration range of 10 −1–10 −5 M, with good long term stability. 相似文献
11.
The synthesis, spectroscopic, and crystal structures of three heteroleptic thioether/halide platinum(II) (Pt(II)) complexes of the general formula [Pt(9S3)X 2] (9S3=1,4,7-trithiacyclononane, X=Cl −, Br −, I −) are presented. All three 9S3/dihalo complexes form very similar structures in which the Pt(II) center is surrounded by a cis arrangement of two halides and two sulfur atoms from the 9S3 ligand. The third sulfur from the 9S3 forms a long distance interaction with the Pt center resulting in an elongated square pyramidal structure with a S 2X 2+S 1 coordination geometry. The distances between the Pt(II) center and axial sulfur shorten with larger halide ions (Cl −=3.260(3) Å>Br −=3.243(2) Å>I −=3.207(2) Å). These distances are consistent with the halides functioning as π donor ligands, and their Pt---S axial distances fall intermediate between Pt(II) thioether complexes involving π acceptor and σ donor ligands. The 195Pt NMR chemical shift values follow a similar trend with an increased shielding of the platinum ion with larger halide ions. The 9S3 ligand is fluxional in all of these complexes, producing a single carbon resonance. Additionally, a related series of homoleptic crown thioether complexes have been studied using 195Pt NMR, and there is a strong correlation between the chemical shift and complex structure. Homoleptic crown thioethers show the anticipated upfield chemical shifts with increasing number of coordinated sulfurs. Complexes containing four coordinated sulfur donors have chemical shifts that fall in the range of −4000 to −4800 ppm while a value near −5900 ppm is indicative of five coordinated sulfurs. However, for S 4 crown thioether complexes, differences in the stereochemical orientation of lone pair electrons on the sulfur donors can greatly influence the observed 195Pt NMR chemical shifts, often by several hundred ppm. 相似文献
12.
Reaction of [Pt 2(η 5-C 5Me 5) 2(η-Br) 3] 3+(Br −) 3 with C 5R 5H (R = H,Me) in the presence of AgBF 4 gives the first platinocenium dications, [Pt(η 5-C 5Me 5)(η 5-C 5R 5)] 2+(BF 4− ) 2. On electrochemical reduction, [pt(η 5-C 5Me 5) 2] 2+ yields [Pt(η 4-C 5Me 5H)(η 2-C 5Me 5)]+ BF 4−. kw]Cyclopentadienyl; Metallocenes; Platinum; Electrochemistry 相似文献
13.
The coordinatively unsaturated cluster [Pt 3(μ 3-CO)(μ-dppm) 3] 2+ (1, dppm = Ph 2PCH 2PPh 2) reacts with Na +[M(CO) 5] − to give the mixed metal clusters [Pt 3{M(CO) 3}(μ-dppm) 3] + (M = Re, 2; Mn, 3). The new clusters are characterized by spectroscopic methods and, for M = Re, by an X-ray structure determination. The Pt 3Re core in 2 is tetrahedral with particularly short metal-metal distances. 相似文献
14.
The nucleophile [ArTe −] generated in situ borohydride solution of Ar 2Te 2, reacts with 2-(chloromethyl) tetrahydrofuran and 2-(2-bromoethyl)-1,3-dioxolane resulting in L 1 and L 2, respectively. The complexes of palladium(II) and platinum(II) with L 1/L 2 having stoichiometries [MCl 2·L 2], [ML 2](ClO 4) 2, [(DPPE)ML 2](ClO) 4) 2, [(PPh 3) 2ML 2](ClO 4) 2 and [(phen)ML 2](ClO 4) 2 (where L = L 1/L 2 DPPE = Ph 2PC H 2CH 2PPh 2, PHEN = 1,10-phenanthroline and M = Pd/Pt) have been synthesized. IR, 1H, 125Te{ 1H} and 31P{ 1H} NMR and UV-vis spectral data of these species in conjunction with their molar conductance and molecular weight data have been used to authenticate the new species. In all complexes (1–20) the ligands L 1 and L 2 are coordinated through tellurium and in the complexes of formula [ML 2](ClO 4) 2 (M = Pd, Pt) the ligand is bidentate with the oxygen atom used in complexation. In solution, complexes PtCl 2L 2 exist as a mixture of cis and trans isomers whereas only the trans isomer was observed for the palladium analogues. The [(phen)PdL 2](ClO 4) 2(Q) quenches 1O 2 readily. The plot of log [Q] vs time is linear. Mechanism compatible with the experimental observations is proposed. 相似文献
15.
The complexes [M(C 6F 5) 2(BIP)] (M = Pd II or Pt II, BIP = 2,6-bis[(1-phenylimino)ethyl]pyridine) have been synthesised and characterised as involving BIP as a bidentate chelate ligand. In solution they undergo 1,4 metallotropic shifts of the M(C 6 F 5) 2 moiety, E,Z isomerisation of the pendant imine bond, and restricted C-C rotation of the pendant portion of the BIP ligand. 1H and 19F dynamic NMR studies yielded activation energies for these three types of fluxion. Δ G≠ (298 K) values for the three processes were 89.6, 86.6 and 47.4kJmol −1 respectively for the Pt II complex. Values for the Pd II complex were significantly lower in magnitude, namely 71.6, 70.4 and 41.8 kJ mol −1 respectively. 相似文献
16.
The oxidation of Cp 2MCl 2 (M= Mo, W) with perfluortriazinium tetrafluoroborate, [(FCN) 3F] +[BF 4] −, in the presence of a flouride ion acceptor (BF 3 or PF 5) in SO 2 solution yielded the cationic metallocene complexes [Cp 2MCl 2] 2+[BF 4] − or [C p2MCl 2] 2+[BF 4] −[PF 6] − (M = Mo, W), respectively. In these reactions, for the first time the perfluortriazinium cation has proved to be easy to handle and a useful oxidizer in organometallic chemistry. The oxidizer strength of three fluorotriazinium cations, [(XCN) 3F] + (X = F, Cl, H), has been computed ab initio (HF/6 − 31 + G) and calibrated on literature data which were obtained by local density functional calculations. It was anchored to its F + zero point by an experimental value for KrF +. ab]Die Oxidation von Cp 2MCl 2 mit (M = MO, W) Perfluortriaziniumtetrafluoroborat, [(FCN) 3F] +[BF 4] −, in Anwesenheit eines Fluoridionenakzeptors (BF 3 oder PF 5) führte in SO 2-Lösung zur Bildung der kationischen Metallocen-Komplexe [Cp 2MCl 2+] 2+[BF 4] 2− bzw. [Cp 2MCl 2] 2+[BF 4] − [PF 6] − (M = Mo, W). In diesen Reaktionen konnte erstmals gezeigt werden, daß Perfluortriazinium-Kationen einfach zu handhabende und nützliche Oxidationsmittel im Bereich der metallorganischen Synthese darstellen. Das (Mdationsvermögen von drei Fluorotriazinium-Kationen, [(XCN) 3F] +(X = F, Cl, H), wurde ab initio berechnet (HF/6 − 31 + G) und mit Hilfe von Literaturdaten, die mittels local density functional-Berechnungen erhalten und am experimentellen Wert von KrF + bezüglich des F + Nullpunktes verankert wurden, kalibriert. 相似文献
17.
Oxidative addition of ethyl iodide to PdMe 2(2,2′-bipyridyl) in (CD 3) 2CO gives the unstable “PdIMe 2Et(bpy)”, which undergoes reductive elimination to form PdIR(bpy) (R = Me, Et), ethane, and propane. Ethene and palladium metal are also formed, and are attributed to decomposition of PdIEt(bpy) via β-elimination. Similar results are obtained with n-propyl iodide, although a palladium(IV) intermediate was not detected, but CH 2=CHCH 2X (X = Br, I) and PhCH=CHCH 2Br give isolable complexes fac-PdXMe 2(CH 2CH=CHR)(L 2) (R = H, Ph; L 2 = bpy, phen). The propenyl complexes decompose at ambient temperature to form ethane, a trace of PdXMe(L 2), and mixtures of [Pd(η 3-C 3H 5)(L 2)]X and [Pd(η 3-C 3H 5)(L 2)]-[Pd(η 3-C 3H 5)X 2]; for fac-PdBrMe 2(CH 2CH=CH 2)(bpy) the major palladium(II) product is [Pd(η 3-C 3H 5)(bpy)]Br. 相似文献
18.
The four-coordinate tin(II) complex [η 4-Me 8taa]Sn undergoes oxidative addition of I 2 to give six-coordinate [η 4-Me 8taa]SnI 2, in which the iodide ligands exhibit a trans arrangment. Abstraction of I − from [η 4-Me 8taa]SnI 2 is facile, as indicated by the rapid formation of the triiodide derivative *[η 4-Me 8taa]SnI(THF)**I 3* upon treatment with I 2 in the presence of THF. The molecular structures of [η 4-Me 8taa]SnI 2 and *[η 4-Me 8taa]SnI(THF)**I 3* have been determined by X-ray diffraction. 相似文献
19.
Binuclear complexes [{Cu(NN)(PhNHpy)} 2(μ-OH) 2](PF 6) 2, where NN=2,2′-bipyridine (bipy) or 1,10-phenanthroline (phen), have been synthesized and characterized by chemical analysis, conductance measurements and IR and electronic spectroscopy. The X-ray crystal structure of [{Cu(bipy)(PhNHpy)} 2(μ-OH) 2](PF 6) 2 shows a distorted square-planar pyramidal coordination for Cu(II), defined by two nitrogen atoms of bipy, two bridging oxygen atoms and the pyridinic nitrogen atom of the ligand. Magnetic susceptibility measurements (in the 4.8–290 K range) reveal coupling which is antiferromagnetic for the bipy complex (2 J=−24.2 cm −1) and slightly ferromagnetic for the phen complex (2 J=3.3 cm −1). The EPR spectra show the expected triplet signals. 相似文献
20.
Through the oxidation-reduction combination procedure, the neutral tri-substituted {2Fe3S} complex 2 was synthesized by replacing the CO ligand in 1 with phosphine. This substitution leads to the Fe-Fe bonds in 1 and 2 with large Lewis basicity difference, i.e. △pK aMeCN~10. 相似文献
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