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1.
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
2.
The adducts of O 2 and SO 2 with trans-MeOIr(CO)(PPh 3) 2 are formed in equilibria and have been characterized. Reaction of the SO 2 adduct, Ir(OMe)(SO 2)(CO)(PPh 3) 2 with dioxygen leads to the sulfato complex, Ir(Ome)(CO)(PPh 3) 2(SO 4), the structure of which has been determined. Ir(Ome)(CO)(PPh 3) 2(SO 4) crystallizes in the monoclinic system with a 11.958(2), b 14.163(3), c 12.231(2) Å, β 118.365(12)°, V 1822.7(6) Å 3 and Z = 2. Diffraction data for 2θ = 4.5–45.0° (Mo- K) were collected with a Syntex P2 1 diffractometer and the structure was solved (assuming space group P2 1/ m and an unpleasant 2-fold disordered model) and refined to R = 4.8% for all 2512 independent data ( R = 3.5% for those 2042 data with ¦F O¦ > 6σ(¦ F¦)). The iridium(III) atom has a distorted octahedral coordination sphere with trans PPh 3 ligands and a cis-chelating bidentate O, O′-SO 4 group; the structure is completed by mutually cis OMe and CO ligands. 相似文献
3.
The reaction of K[ReH 6(PPh 3) 2] with [RhCl(CO)L 2] [L= PPh 3, 1,2,5-triphenylphosphole (TPP), or P(OMe) 3] leads to the new electronically unsaturated heterobimetallic polyhydride complexes [(CO)(PPh 3) 2HRe(μ-H) 3RhL 2] in moderate-to-good yields. The structures of these complexes have been established on the basis of spectroscopic data, especially 1H and 31P NMR. The bridging hydride ligands are fluxional but there is either a slow or nonexistent exchange between terminal and bridging hydrides. For L = PPh 3 or TPP, protonation with tetrafluoroboric acid affords quantitatively the cationic complexes [(CO)(PPh 3) 2HRe(μ-H) 3RhHL 2] +, isolated as the BF 4− or the BPh 4− salts. 相似文献
4.
The reaction of [(CO)PPh 3) 2Re(μ-H) 2(μ-NCHPh)Ru(PPh 3) 2(PhCN)] (2) with HBF 4-Me 2O generates [(CO)PPh 3) 2Re(μ- H) 2(μ,η 1,η 2HNCHPh)Ru(PPh 3) 2(PhCN)][BF 4] (3). Monitoring the reaction by NMR spectroscopy shows the intermediate formation of [(CO)(PPh 3) 2 HRe(μ-H) 2(μ-NCHPh)Ru(PPh 3) 2(PhCN)][BF 4] (4). Attempted reduction of the imine ligand by a nucleophile (H − or CN −) failed, regenerating 2. Under dihydrogen at 50 atm, 3 is slowly transformed into [(CO)(PPh 3) 2HRe(μ-H) 3Ru(PPh 3) 2(PhCN)][BF 4] (5) with liberation of benzyl amine. 相似文献
5.
The product isolated from the reaction of (μ-H) 2Os 3(CO) 9(PPh 3) with ethylene is shown to be the ethylidene complex (μ-H) 2Os 3(CO) 9(PPh 3)(μ-CHCH 3) (1) rather than the ethylene complex (μ-H)(H)Os 3(CO) 9(PPh 3)(C 2H 4), as previously claimed. The characterization of 1 is based on a combination of 1H and 13C NMR results. The 1H NMR data (δ 6.84 (1 H D), 2.53 (3 H C), J(CD) = 7.4 Hz) establish the presence of the ethylidene moiety, whereas detailed analysis of the 1-D and 2-D 13C NMR spectra of 13CO-enriched 1 indicates the relative positions of the ethylidene, hydride, and phosphine ligands on the triosmium framework. 相似文献
6.
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
7.
The compound [RU 3(μ 3,η 2- -ampy)(μ 3η 1:η 2-PhC=CHPh)(CO) 6(PPh 3) 2] (1) (ampy = 2-amino-6-methylpyridinate) has been prepared by reaction of [RU 3(η-H)(μ 3,η 2- ampy) (μ,η 1:η 2-PhC=CHPh)(CO) 7(PPh 3)] with triphenylphosphine at room temperature. However, the reaction of [RU 3(μ-H)(μ 3, η 2 -ampy)(CO) 7(PPh 3) 2] with diphenylacetylene requires a higher temperature (110°C) and does not give complex 1 but the phenyl derivative [RU 3(μ 3,η 2-ampy)(μ,η 1:η 2 -PhC=CHPh)(μ,-PPh 2)(Ph)(CO) 5(PPh 3)] (2). The thermolysis of complex 1 (110°C) also gives complex 2 quantitatively. Both 1 and 2 have been characterized by0 X-ray diffraction methods. Complex 1 is a catalyst precursor for the homogeneous hydrogenation of diphenylacetylene to a mixture of cis- and trans -stilbene under mild conditions (80°C, 1 atm. of H 2), although progressive deactivation of the catalytic species is observed. The dihydride [RU 3(μ-H) 2(μ 3,η 2-ampy)(μ,η 1:η 2- PhC=CHPh)(CO) 5(PPh 3) 2] (3), which has been characterized spectroscopically, is an intermediate in the catalytic hydrogenation reaction. 相似文献
8.
The molecular and crystal structure of the nido-6-tungstadecaborane [6,6,6,6-(CO) 2(PPh 3) 2- nido-6-WB 9H 13] (1) has been determined showing that the tungsten atom is incorporated into the 6-position of a nido 10-vertex (WB 9) cage. The tungsten atom has a seven-coordinate capped trigonal prismatic environment and is bonded to two hydrogen and three boron atoms of the {B 9H 13} cage, in addition to two CO groups and two PPh 3 ligands. Variable-temperature (−90°C to +50°C) 31P{ 1H} NMR spectroscopy of 1 reveals that the exo-polyhedral ligands about the tungsten atom are fluxional with respect to PPh 3 site exchange with an activation energy (Δ G‡), at the coalescence temperature (−73°C), of <38 kJ mol −1. 相似文献
9.
Rhodium(I) complexes [Rh(TropNMe)(CO)(PPh 3)] (TropNMe = 2-( N-methylamino)tropone, ONC 8H 9) (1) and [Rh(Trop)(CO)(PPh 3)] · Acetone (Trop = Tropolone, O 2C 7H 6) (2) have been synthesized and characterized by single-crystal X-ray diffraction analysis. A distorted square planar geometry about the rhodium(I) metal centre is observed in both compounds 1 and 2. Substitution of an oxygen atom with a methyl functionalized nitrogen atom does not significantly alter the bond distances and angles in the rhodium(I) complex. A theoretical study at B3LYP/6-31G(d) (main group) and LANL2DZ (Rh) level is presented to clarify the solid state behaviour of these complexes. 相似文献
10.
The hydroxo-complexes [{PdR(PPh 3)(μ-OH)} 2] (R = C 6F 5 or C 6Cl 5) have been obtained by reaction of the corresponding [{PdR(PPh 3)(μ-Cl)}2] complexes with NBu 4OH in acetone. In this solvent, the reaction of the hydroxo-bridged complexes with pyrazole (Hpz) and 3,5-dimethylpyrazole (Hdmpz) in 1:2 molar ratio leads to the formation of the new complexes [{Pd(C 5F 5)(PPh 3)(μ-azolate)}2] and [{Pd(C 6Cl 5)(PPh 3)} 2(μ-OH)(μ-azolate)] (azolate = pz or dmpz). The reaction of the bis(μ-hydroxo) complexes with Hpz and Hdmpz in acetone in 1:1 molar ratio has also been studied, and the resulting product depends on the organic radical (C 6F 5 or C 6Cl 5) as well as the azolate (pz or dmpz). The identity of the isomer obtained has been established in every case by NMR ( 1H, 19F and 31P) spectroscopy. The reaction of the bis(μ-hydroxo) complexes with oxalic (H 2Ox) and acetic (HOAc) acids yields the binucle ar complexes [{PdR(PPh 3)}2(μ-Ox)] (R = C 6F 5 or C 6Cl 5) and [{Pd(C 6F 5)(PPh 3)(μ-OAc)}2], respectively. [{Pd(C 6F 5)(PPh 3)(μ-OH)} 2] reacts with PPh 3 in acetone in 1:2 ratio giving the mononuclear complex trans-[Pd(C 6F 5) (OH)(PPh 3) 2], whereas the pentachlorophenylhydroxo complex does not react with PPh 3, even under forcing conditions. 相似文献
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