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1.
The nitrosyl complexes trans-[ReCl(NO)(dppe) 2]A 2 (1; A = BF 4 or NO 3; dppe = Ph 2PCH 2CH 2−PPh 2) and trans-[ReCl(NO)(dppe) 2][BF 4] (2) have been prepared from the reactions of NO[BF 4] or NO with trans-[ReCl(N 2)dppe) 2]. An unusual facile oxidation of NO to nitrate is involved in the formation of (1, A = NO 3), the X-ray structure of which is reported. 相似文献
2.
Reaction of trans-[ReCl(CNR)(dppe) 2] (R = Me (Ia) or tBu (Ib); DPPE = Ph 2PCH 2CH 2PPh 2) in CH 2Cl 2 with cynamide in the presence of TlBF 4 forms the new cynamide-isocyanide complexes trans-[Re(CNR)(NCNH 2)(dppe) 2][BF 4] (R = Me (IIa) or tBu (IIb)), which upon treatment by tBuOK or Et 3N give trans-[Re(NCNH)(CNR)(dppe) 2] (R = Me (IIIa) or tBu (IIIb)). The electrochemical behaviour of these species was studied by cyclic voltammetry and controlled potential electrolysis at a Pt electrode in an aprotic solvent, and cathodic reduction of II results in the formation of III. 相似文献
3.
Complexes of the types (a) trans- and cis-[Pd(C 6X 5) 2 (CNR) 2], (b) trans- [Pd(C 6X 5)Cl(CNR) 2] and (c) [Pd(C 6X 5)(CNR) 3]ClO 4 (X = F or Cl;R = Bu t cyclohexyl or p-tolyl) have been made by replacement of the tetrahydrothiophen or Cl groups of appropriate precursors by isonitrile. Their structures have been assigned on the basis of their IR and 1H NMR spectra. 相似文献
4.
The siloxyanilines o-Me 3SiOC 6H 4NH 2 (1) and p-RMe 2SiOC 6H 4NH 2 (R=H (2); R=Me (3)), and their N-silylated derivatives p-Me 3SiOC 6H 4NHSiMe 3 (4) and p-Me 3SiOC 6H 4N(SiMe 3) 2 (5) have been prepared from ortho- or para-aminophenol and used in the synthesis of imido complexes. Thus, binuclear [{Ti(η 5-C 5H 5)Cl}{μ-NC 6H 4( p-OSiMe 3)}] 2 (6) and mononuclear [TiCl 2{NC 6H 4( p-OSiMe 3)}(py) 3] (7) imido complexes have been obtained from the reaction of 3 and [Ti(η 5-C 5H 5)Cl 3] or [TiCl 2(N tBu)(py) 3], respectively. In contrast, the reaction of 1 with TiCl 4 and tBupy affords the titanocycle [TiCl 2{OC 6H 4( o-NH)---N,O}( tBupy) 2] (8). Compound 5 has also been used to prepare the niobium imide complex [NbCl 3{NC 6H 4( p-OSiMe 3)}(MeCN) 2] (9), by its reaction with NbCl 5 in CH 3CN. These findings have been applied to the synthesis of polynuclear systems. Thus, chlorocarbosilane Si[CH 2CH 2CH 2Si(Me) 2Cl] 4 (CS–Cl) has been functionalized with the ortho- and para-aminophenoxy groups to give 10 and 11, respectively. The use of 11 has allowed the formation of the tetranuclear compound 12. Attempts to synthesize terminal imido titanium complexes from 10 and TiCl 4 in the presence of tBupy and Et 3N, give complex 8 and carbosilane CS–Cl. 相似文献
5.
Complexes trans-[PtX(L)(PPh 3) 2]A [1: X = CF 3; A = BF 4; L = NCNH 2, NCNMe 2, NCNEt 2, or NCNC(NH 2) 2. 2: X = Cl; A = BPh 4; L = NCNMe 2 or NCNEt 2] and cis-[PtCl(L)(PPh 3) 2][BPh 4] [3: L = NCNH 2 or NCNC(NH 2) 2], which appear to be the first cyanamide or cyanoguanidine complexes of platinum to be reported, have been prepared by treatment of trans-[PtBr(CF 3)(PPh 3) 2] (in CH 2Cl 2/acetone and in the presence of Ag[BF 4]) or of cis-[PtCl 2(PPh 3) 2] (in THF and in the presence of Na[BPh 4]), respectively, with the appropriate substrate. In KBr pellets or in solution 1 (L = NCNMe 2 or NCNEt 2) undergoes ready replacement of the organocyanamide (under the trans influence of CF 3) by bromide to regenerate trans-(PtBr(CF 3)(PPh 3) 2]. The X-ray structure of 1 (X = CF 3, A = BF 4, L = NCNEt 2) is also reported, and shows the presence of two apical intramolecular contacts of the metal with two ortho-hydrogen atoms of the phosphines, whereas the amine N atom of the diethylcyanamide is trigonal planar in the linear NCN framework with a delocalized π system. 相似文献
6.
Reaction of cis-[Ptph 2(SMe 2) 2] with Me 2PCH 2PMe 2 (dmpm) gave cis-[PtPh 2(dmpm-P) 2] (1) or cis,cis-[Pt 2Ph 4(μ-dmpm) 2] (2) and reaction of 1 with [Pt 2Me 4(μ-SMe 2) 2] gave cis,cis-[Ph 2Pt(μ-dmpm) 2PtMe 2] (3). Reaction of 1 with trans-[PtClR(SMe 2) 2] gave cis, trans-[Ph 2Pt(μ-dmpm) 2PtClR], R = Me (5) or Ph (6), and in polar solvents, these isomerized to give [Ph 2Pt(μ-dmpm) 2PtR] +Cl −. When R = Me, further isomerization via the phenyl group transfer gave [PhMePt(μ-dmpm) 2PtPh] +Cl −. Oxidative addition of methyl iodide occurred reversibly at the cis-[PtMe 2P 2 unit of 3 to give cis, fac-[Ph 2Pt(μ-dmpm) 2PtIMe 3] but complex 2 failed to react with MeI. A comparison with similar known complexes of Ph 2PCH 2PPh 2 (dppm) is made and differences are attributed primarily to the lower steric hindrance of dmpm. 相似文献
7.
Reaction of trans-[Pt(H) 2(PCy 3) 2], 1, with [60]fullerene at room temperature affords [Pt(PCy 3) 2( η2-C 60)], 2, in nearly quantitative yield. The most probable reaction pattern is the insertion of a fullerene 6,6 junction onto a Pt-H bond yielding an η1 alkyl derivative which, after hydrogen extrusion, gives 2. On the other hand, addition of 1 to different electron-deficient olefins, such as dimethyl maleate and fumarate, furnishes mixtures of both η1 metal—alkyl and η2 metal—olefin derivatives. If tetrachloroethylene is used as 2 π component, trans-[PtCl(H)(PCy 3) 2] forms exclusively. 相似文献
8.
Compounds of the types Me 3PtX(NN) (where X = Cl, I, OAc, NO 3; NN = bis(1-pyrazolyl)methane (pz 2CH 2), bis(3,5-dimethyl-1-pyrazolyl)methane ((Me 2pz) 2CH 2), or bis(2-pyridyl)methane (py 2CH 2)), [Me 3Pt(NNN)][PF 6] (where NNN=tris(1-pyrazolyl)methane (pz 3CH), or tris(2-pyridyl)methane (py 3CH)), and [Me 3Pt((Me 2pz) 2CH 2(py)][PF 6] have been prepared and characterized by elemental analyses and 1H and 13C NMR spectroscopy; the structure of Me 6PtI[(Me 2pz) 2CH 2] (1) has also been determined by X-ray crystallography. Crystals of 1 are orthorhombic, space group Pcmn with four molecules in a unit cell of dimensions a 11.936(5), b 14.462(4), c 10.138(5) Å. The structure was solved by the heavy-atom method and refined by full-matrix least-squares calculations to R = 0.022 for 1719 observed data. The molecule has crystallographic mirror symmetry. The Pt atom has octahedral geometry with one methyl group trans to iodine and two methyl groups trans to the N atoms of the bidentate ligand (Pt---I 2.843(1), Pt---N, 2.236(4), Pt---C 2.077(6) ( trans to I) and 2.032(5) Å ( trans to N)). 相似文献
9.
The complexes trans-[Os(CCPh)Cl(dppe) 2] (1), trans-[Os(4-CCC 6H 4CCPh)Cl(dppe) 2] (2), and 1,3,5-{ trans-[OsCl(dppe) 2(4-CCC 6H 4CC)]} 3C 6H 3 (3) have been prepared. Cyclic voltammetric studies reveal a quasi-reversible oxidation process for each complex at 0.36–0.39 V (with respect to the ferrocene/ferrocenium couple at 0.56 V), assigned to the Os II/III couple. In situ oxidation of 1–3 using an optically transparent thin-layer electrochemical (OTTLE) cell affords the UV–Vis–NIR spectra of the corresponding cationic complexes 1 +–3 +; a low-energy band is observed in the near-IR region (11 000–14 000 cm −1) in each case, in contrast to the neutral complexes 1–3 which are optically transparent below 20 000 cm −1. Density functional theory calculations on the model compounds trans-[Os(CCPh)Cl(PH 3) 4] and trans-[Os(4-CCC 6H 4CCPh)Cl(PH 3) 4] have been used to rationalize the observed optical spectra and suggest that the low-energy bands in the spectra of the cationic complexes can be assigned to transitions involving orbitals delocalized over the metal, chloro and alkynyl ligands. These intense bands have potential utility in switching nonlinear optical response, of interest in optical technology. 相似文献
10.
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
11.
The equilibrium constants of the reaction of cis, trans-[Ru(CO) 2(PMe 3) 2(CH 3)I] (Mc) with carbon monoxide to give cis, trans[Ru(CO) 2(PMe 3) 2 (COMe)i] (Ac) and trans, trans[Ru(CO) 2(PMe 3) 2(COMe)I] (At) were measured at various temperatures in toluene. The thermodynamic parameters are compared with those obtained for the isoelectronic complexes of iron, and the trend is discussed. The kinetics of the carbonylation reaction of Mc, as well as those of the inverse decarbonylation reaction of At were measured. The kinetics of the carbonylation of the new complex trans, trans-[Ru(CO) 2(PMe 3) 2(CH 3)I] (Mt) were also investigated. All the results afford further support to the previously proposed CO insertion mechanism occurring via methyl migration. The comparison of these kinetic results with those of isoelectronic complexes of iron indicates that ruthenium is more reactive than iron, which is reflected by its greater aptitude to act as catalyst in many processes. 相似文献
12.
Several ruthenium(II) mono(acetylides) trans-[Cl(dppe) 2Ru---(CC) n---R] ( n=1–4; R=SiMe 3, H) and bis(acetylide) trans-[(dppe) 2Ru(---(CC) 2---R) 2] (R=SiMe 3, H) were selectively obtained and could be used as a new set of building blocks for rigid rod-like structures and further assemblies. Especially, the oxidative coupling of trans-[Cl(dppe) 2Ru---(CC) 3---H] with Cu(OAc) 2 led to the formation of the first Ruthenium(II) binuclear species with 12 carbon atoms between the remote metals. This compound shows two reversible redox processes. 相似文献
13.
Carbon---hydrogen bond cleavage at the terminal 6-position occurs when hex-5-en-2-one (CH 2=CHCH 2CH 2COMe) oxidatively adds to [Os 3(CO) 10(MeCN) 2] to give [Os 3H(μ-CH=CHCH 2CH 2COMe)(CO) 10], which is completely analogous to the simple vinyl complex [Os 3H(μ-CH=CH 2)(CO) 10]. A minor product from the reaction is [Os 3(CH 3CH=CHCH 2COMe)(CO) 10], an isomer in which double-bond migration has occurred to give the βγ-unsaturated ketone; stabilisation occurs through chelation and ketone coordination. [Os 3H 2(CO) 10] reacts with CH 2=CHCH 2CH 2COMe in refluxing cyclohexane to give a third isomer, [Os 3H(CH 3CH 2C=CHCOMe)(CO) 10], in which further double bond migration has occurred to give the β-unsaturated ketone. Metallation at the β-site gives an Os---C bond as part of a 5-membered chelate ring. Thermolysis of each of the three isomeric decarbonyl species in refluxing cyclohexane or heptane leads to the elimination of an Os(CO) 4 group to give the dinuclear compound [Os 2H(EtC=CHCOMe)(CO) 6] in varying yield. Pathways from γδ to the βγ and finally the β unsaturated ketones may be mapped out. 相似文献
14.
The preparation of a series of new square-planar and half-sandwich type carbenerhodium(I) complexes will be described. The key to success is the use of the bis(stibane)rhodium compound trans-[RhCl(C 2H 4)(Sb iPr 3) 2] as starting material from which in a stepwise manner the complexes trans-[RhCl(=CRR′)(Sb iPr 3) 2] (L = P iPr 3, As iPr 3, SbEt 3) and [C 5H 5Rh(=CCR′)L] (L = Sb iPr 3, P iPr 3, PMe 3, CO, CN tBu) have been obtained. Displacement of the carbene ligand in either trans-[RhCl(=CPH 2)L 2]L = Sb iPr 3, P iPr 3 or [C 5H 5Rh(=CPh 2)(P iPr 3)] by CO or CN tBu leads to the formation of the corresponding carbonyl- or isocyanidrhodium compounds and the C---C coupling products Ph 2C=C=O and Ph 2C=C=N tBu, respectively. The carbene ligand is also involved in the selective formation of the isomeric olefins CH 2=CHCPh 2H and Ph 2C=CHCH 3 on treatment of trans-[RhCl(=CPh 2)(Sb iPr 3) 2] and trans-[RhCl(=CPh 2)(P iPr 3) 2] with ethene. The most spectacular reaction of the bis(triisopropylstibane) complexes, however, occurs on warming of trans-[RhCl(=CRR′)(Sb iPr 3) 2] in the absence of any substrate which yields the first representatives of dinuclear transition-metal compounds containing a tertiary stibane ligand in a bridging position. Some exploratory studies on the reactivity of the Rh 2(μ-Sb iPr 3) complexes indicate that the triisopropylstibane can be replaced by SbMe 3, SbEt 3 or CN tBu without destroying the dimetallic core of the molecule. 相似文献
15.
The dimethylphosphino substituted cyclopentadienyl precursor compounds [M(C 5Me 4CH 2PMe 2)], where M=Li + (1), Na + (2), or K + (3), and [Li(C 5H 4CR′ 2PMe 2)], where R′ 2=Me 2 (4), or (CH 2) 5 (5), [HC 5Me 4CH 2PMe 2H]X, where X −=Cl − (6) or PF 6− (7) and [HC 5Me 4CH 2PMe 2] (8), are described. They have been used to prepare new metallocene compounds, of which representative examples are [Fe(η-C 5R 4CR′ 2PMe 2) 2], where R=Me, R′=H (9); R=H and R′ 2=Me 2 (10), or (CH 2) 5 (11), [Fe(η-C 5H 4CMe 2PMe 3) 2]I 2 (12), [Fe{η-C 5Me 4CH 2P(O)Me 2} 2] (13), [Zr(η-C 5R 4CR′ 2PMe 2) 2Cl 2], where R=H, R′=Me (14), or R=Me, R′=H (15), [Hf(η-C 5H 4CMe 2PMe 2) 2]Cl 2] (16), [Zr(η-C 5H 4CMe 2PMe 2) 2Me 2] (17), {[Zr(η-C 5Me 4CH 2PMe 2) 2]Cl}{(C 6F 5) 3BClB(C 6F 5) 3} (18), [Zr{(η-C 5Me 4CH 2PMe 2) 2Cl 2}PtI 2] (19), [Mn(η-C 5Me 4CH 2PMe 2) 2] (20), [Mn{(η-C 5Me 4CH 2PMe 2B(C 6F 5) 3} 2] (21), [Pb(η-C 5H 4CMe 2PMe 2) 2] (23), [Sn(η-C 5H 4CMe 2PMe 2) 2] (24), [Pb{η-C 5H 4CMe 2PMe 2B(C 6F 5) 3} 2] (25), [Pb(η-C 5H 4CMe 2PMe 2) 2PtI 2] (26), [Rh(η-C 5Me 4CH 2PMe 2)(C 2H 4)] 29, [M(η,κ P-C 5Me 4CH 2PMe 2)I 2], where M=Rh (30), or Ir, (31). 相似文献
16.
The complexes [Ru(S,S) 2(PPh 3) 2] [S,S = EtCOCS 2−, (CH 2) 4NCS 2−] react with a variety of tertiary phosphines with the substitution of triphenylphosphine and the formation of [Ru(S,S) 2(PR 3) 2]. The reaction occurs with the formation ofthe cis isomer, except for the complex with PMe 2Ph that gives rise to the trans isomer as the crystal structure shows. The effect of the different phosphines on the ruthenium complex is analysed in terms of the spectroscopic and electrochemical properties of the isolated compounds. The cyclic voltammetric studies of the cis complexes show that isomerization to the trans isomer occurs on oxidation. This isomerization is not observed in the trans-[Ru(S,S) 2(PMe 2Ph) 2] complexes that give rise to stable trans-ruthenium(II)/ruthenium(III) couples. In a similar way the diphosphine complexes afford a quasi-reversible cis-ruthenium(II)/ruthenium(III) process. 相似文献
17.
13C and 31P{ 1H} NMR data at low temperature prompted us to characterize cis-[Rh(CO) 2(PR 3)Cl] (3) (3a, PR 3 = PPh 3; 3b, PR 3 = PMe 2Ph), as surprisingly stable products of the reaction between [{Rh(CO) 2(μ-Cl)} 2] (1) and tertiary phosphines in toluene (P : Rh = 1). Every attempt to isolate solid 3a led to the cis- and trans- halide-bridged dimers [{Rh(CO) 2(μ-Cl)} 2] (5a) and 6a which are formed from 3a by slow decarbonylation, a process which is greatly accelerated by the evaporation of the solvent under vacuum. The analogous reaction of 1 with dimethylphenylphosphine follows a similar pathway; in this case, however, low temperature NMR spectra allowed us to characterize the pentacoordinated dinuclear species [{Rh(CO)2(μ-Cl)}2] (2b) as the unstable intermediate of the bridge-splitting process. The reaction of 3 with a second equivalent of phosphine (P : Rh = 2) leads, at room temperature, to the well known product trans-[Rh(CO)(PR3)2Cl] (8) accompanied by evolution of CO; however our data show that when the reaction is performed at 200 K, decarbonylation is prevented and spectroscopic evidence of trigonal bipyramidal pentacoordinate [Rh(CO)2(PR3)2Cl] (7), stable only at low temperature, can be obtained. 相似文献
18.
Reaction of trans-HM(PEt 3) 2 (CCC 6H 5) (M = Pt, Pd) with dimethyl acetylenedicarboxylate has given rans-{(CH 3O 2C)HC=C(CO 2CH 3)}M(PEt 3) 2 (CCC 6H 5). It is suggested that oligomerization of a terminal acetylene proceeds through an alkynylalkenyl derivative. 相似文献
19.
Treatment of [Ru 2(CO) 4(MeCN) 6][BF 4] 2 or [Ru 2(CO) 4(μ-O 2CMe) 2(MeCN) 2] with uni-negative 1,1-dithiolate anions via potassium dimethyldithiocarbamate, sodium diethyldithiocarbamate, potassium tert-butylthioxanthate, and ammonium O, O′-diethylthiophosphate gives both monomeric and dimeric products of cis-[Ru(CO) 2(η 2-(SS)) 2] ((SS) −=Me 2NCS 2− (1), Et 2NCS 2− (2), tBuSCS 2− (3), (EtO) 2PS 2− (4)) and [Ru(CO)(η 2-(Me 2NCS 2))(μ,η 2-Me 2NCS 2)] 2 (5). The lightly stabilized MeCN ligands of [Ru 2(CO) 4(MeCN) 6][BF 4] 2 are replaced more readily than the bound acetate ligands of [Ru 2(CO) 4(μ-O 2CMe) 2(MeCN) 2] by thiolates to produce cis-[Ru(CO) 2(η 2-(SS)) 2] with less selectivity. Structures 1 and 5 were determined by X-ray crystallography. Although the two chelating dithiolates are cis to each other in 1, the dithiolates are trans to each other in each of the {Ru(CO)(η 2-Me 2NCS 2) 2} fragment of 5. The dimeric product 5 can be prepared alternatively from the decarbonylation reaction of 1 with a suitable amount of Me 3NO in MeCN. However, the dimer [Ru(CO)(η 2-Et 2NCS 2)(μ,η 2-Et 2NCS 2)] 2 (6), prepared from the reaction of 2 with Me 3NO, has a structure different from 5. The spectral data of 6 probably indicate that the two chelating dithiolates are cis to each other in one {Ru(CO)(η 2-Et 2NCS 2) 2}fragment but trans in the other. Both 5 and 6 react readily at ambient temperature with benzyl isocyanide to yield cis-[Ru(CO)(CNCH 2Ph)(η 2-(SS)) 2] ((SS)=Me 2NCS 2− (7) and Et 2NCS 2− (8)). A dimerization pathway for cis-[Ru(CO) 2(η 2-(SS)) 2] via decabonylation and isomerization is proposed. 相似文献
20.
The preparation and properties as well as some reactions of a series of arylcarbonylbis(triphenylphosphine)iridium(I) complexes [Ir(Ar)(CO)(PPh 3) 2] (Ar = C 6H 5, C 6F 5, 2-C 6H 4CH 3, 3-C 6H 4CH 3, 4-C 6H 4CH 3, 2-C 6H 4OCH 3, 2,6-C 6H 3-(OCH 3) 2, 4-C 6H 4N(CH 3) 2, 3-C 6H 4Cl, 4-C 6H 4Cl, 4-C 6H 4Cl, 3-C 6H 4CF 3, 4-C 6H 4CF 3) are described, and the most important IR data as well as the 31P NMR parameters of these, without exception trans-planar, compounds are given. Some of the complexes react with molecular oxygen to form well defined dioxygen adducts [Ir(Ar)(O2)(CO)(PPh3)2] (Ar = C6H5, 3-C6H4CH3, 4-C6H4CH3). Complexes with ortho-substituted aryl ligands are not oxygenated. This effect is referred to as a steric shielding of the metal center by the corresponding ortho-substituents. With SO2 the similar irreversible addition compound [Ir(4-C6H4CH3)-(SO2)(CO)(PPh3)2] is obtained. Sulfur dioxide insertion into the Ir---C bond cannot be observed. The first step of the reaction between [Ir(4-C6H4CH3)(CO)(PPh3)2] and hydrogen chloride involves an oxidative addition of HCl to give [Ir(H)(Cl)(4-C6-H4CH3)(CO)(PPh3)2]. Ir---C bond cleavage by reductive elimination of toluene from the primary adduct does not occur except at elevated temperature. 相似文献
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