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1.
Kinetic and activation parameter data for the reactions of cct-Ru(H)2(CO)2(PPh3)2 (1) (cct = cis, cis, trans) in THF with thiols, CO and PPh3 to give cct-RuH(SR)(CO)2(PPh3)2, Ru(CO)3(PPh3)2 and Ru(CO)2(PPh3)2, respectively, reveal a common, rate-determining step, the initial dissociation of H2 from 1; the activated complex probably resembles the corresponding Ru(η2-H2) species. Reaction of Ru(H)2(dppm)2 (2) (as a cis/trans mixture, DPPM = bis(diphenylphosphino)methane) with thiols initially generated cis- and trans- RuH(SR) (dppm)2 with a rate that depends on both the type and concentration of thiol. The higher basicity of the hydride ligands in 2 (versus 1), which is demonstrated by deuterium exchange with CD3OD, gives rise in the thiol reaction to an initial protonation step prior to loss of H2. A species detected in the thiol reaction is possibly [RuH(η2-H2 (dppm)2]2, the anticipated intermediate for this reaction and for the hydrogen exchange with alcohol. A longer reaction of 2 with PhCH2SH gives solely cis-Ru(SCH2Ph)2(dppm)2. 相似文献
2.
The dinuclear Pt---Si complex {(Ph3P)Pt{μ-η2-H---SiH(IMP)]}2 (trans-1a–cis-1b=3:1; IMP=2-isopropyl-6-methylphenyl) reacted with basic phosphines such as 1,2-bis(diphenylphosphino)ethane (dppe) and dimethylphenylphosphine (PMe2Ph) to afford different dinuclear Pt---Si complexes with loss of H2, {(P)2Pt[μ-SiH(IMP)]}2 [P=dppe, trans-2a (major), cis-2b (trace); PMe2Ph, 3 (trans only)]. Complexes 2 and 3 were characterized by multinuclear NMR spectroscopy and X-ray crystallography (2a). In contrast, the reaction of 1a,b with the sterically demanding tricyclohexylphosphine (PCy3) afforded {(Cy3P)Pt{μ-η2-H---SiH(IMP)]}2 (trans-4a–cis-4b 2:1) analogous to 1a,b where the central Pt2Si2(μ-H)2 core remains intact but the PPh3 ligands have been replaced by PCy3. Complexes 4a and 4b was characterized by multinuclear NMR and IR spectroscopies. 相似文献
3.
A. M. Cano J. Cano T. Cuenca P. Gmez-Sal A. Manzanero P. Royo 《Inorganica chimica acta》1998,280(1-2):1
The reaction of TiCl4 with Li2[(SiMe2)2(η5-C5H3)2] in toluene at room temperature afforded a mixture of cis- and trans-[(TiCl3)2{(SiMe2)2(η5-C5H3)2}] in a molar ratio of 1/2 after recrystallization. The complex trans-[(TiCl3)2{(SiMe2)2(η5-C5H3)2}] was hydrolyzed immediately by the addition of water to THF solutions to give trans-[(TiCl2)2(μ-O){(SiMe2)2(η5-C5H3)2}] as a solid insoluble in all organic solvents, whereas hydrolysis of cis-[(TiCl3)2{(SiMe2)2(η5-C5H3)2}] under different conditions led to the dinuclear μ-oxo complex cis-[(TiCl2)2)(μ-O){(SiMe2)2(η5-C5H3)2}] and two oxo complexes of the same stoichiometry [(TiCl)2(μ-O){(SiMe2)2(η5-C5H3)2}]2(μ-O)2 as crystalline solids. Alkylation of cis- and trans-[(TiCl3)2{(SiMe2)2(η5-C5H3)2}] with MgCIMe led respectively to the partially alkylated cis-[(TiMe2Cl)2{(SiMe2)2(η5-C5H3)2}] and the totally alkylated trans-[(TiMe3)2{(SiMe2)2(η5-C5H3)2}] compounds. The crystal and molecular structure of the tetranuclear oxo complex [(TiCl)2(μ-O){(SiMe2)2(η5-C5H3)2}]2(μ-O)2 was determined by X-ray diffraction. 相似文献
4.
Alan J. Lough Robert H. Morris Leonarda Ricciuto Thomas Schleis 《Inorganica chimica acta》1998,270(1-2):238-246
The complex [Ru(H2)(H)(PMe2Ph)4]PF6 (1) has been prepared by reaction of [Ru(H)(PMe2Ph)5] FP6 (2) in THF with 1 atm H2 and characterised by variable temperature 31P and 1H NMR. It undergoes four distinct fluxional processes listed in order of decreasing activation energy: (i) exchange of H2 in solution with the dihydrogen ligand above 273 K; (ii) isomerisation of cis and trans isomers of 1 above 230 K; (iii) exchange of H atoms between H2 and hydride in trans-1 above 180 K; (iv) rapid H2/hydride exchange in cis-1 to below 180 K. A single crystal X-ray diffraction study of 1 at 173 K shows that the complex has the cis geometry in the solid state but does not clearly reveal the positions of the hydrogen ligands. Complex 1 starts out as a catalyst of high activity for the selective hydrogenation of 1-alkynes to 1-alkenes (RC≡CH; R=11Bu, Ph) but it is rapidly deactivated, possibly because of formation of the enynyl complex [Ru(η3RC3CHR)(PMe2Ph)4]+. Complex 1 efficiently catalyzes the hydrogenation of internal alkynes (3-hexyne, 2-pentyne) to internal cis-alkenes with little deactivation, although some isomerisation of the alkene produced is observed. These observations are consistent with those of Nkosi, Coville, Albers and Singleton who reported that complex 2 must dissociate one PMe2Ph ligand to produce the species active for alkyne hydrogenation. Complex 2 catalyses these hydrogenations with slower initial rates than complex 1 but deactivates less readily. In contrast to 1, complex 2 does not appear to cause the isomerisation of internal alkenes. 相似文献
5.
Umberto Belluco Roberta Bertani Rino A. Michelin Mirto Mozzon Franco Benetollo Gabriella Bombieri Robert J. Angelici 《Inorganica chimica acta》1995,240(1-2):567-574
The chloro complexes trans-[Pt(Me)(Cl)(PPh3)2], after treatment with AgBF4, react with 1-alkynes HC---C---R in the presence of NEt3 to afford the corresponding acetylide derivatives trans-[Pt(Me) (C---C---R) (PPh3)2] (R = p-tolyl (1), Ph (2), C(CH3)3 (3)). These complexes, with the exception of the t-butylacetylide complex, react with the chloroalcohols HO(CH2)nCl (n = 2, 3) in the presence of 1 equiv. of HBF4 to afford the alkyl(chloroalkoxy)carbene complexes trans-[Pt(Me) {C[O(CH2)nCl](CH2R) } (PPh3)2][BF4] (R = p-tolyl, N = 2 (4), N = 3 (5); R=Ph, N = 2 (6)). A similar reaction of the bis(acetylide) complex trans-[Pt(C---C---Ph)2(PMe2Ph)2] with 2 equiv. HBF4 and 3-chloro-1-propanol affords trans-[Pt(C---CPh) {C(OCH2CH2CH2Cl)(CH2Ph) } (PMe2Ph)2][BF4] (7). T alkyl(chloroalkoxy)-carbene complex trans-[Pt(Me) {C(OCH2CH2Cl)(CH2Ph) } (PPh3)2][BF4] (8) is formed by reaction of trans-[Pt(Me)(Cl)(PPh3)2], after treatment with AgBF4 in HOCH2CH2Cl, with phenylacetylene in the presence of 1 equiv. of n-BuLi. The reaction of the dimer [Pt(Cl)(μ-Cl)(PMe2Ph)]2 with p-tolylacetylene and 3-chloro-1-propanol yields cis-[PtCl2{C(OCH2CH2CH2Cl)(CH2C6H4-p-Me}(PMe2Ph)] (9). The X-ray molecular structure of (8) has been determined. It crystallizes in the orthorhombic system, space group Pna21, with a = 11.785(2), B = 29.418(4), C = 15.409(3) Å, V = 4889(1) Å3 and Z = 4. The carbene ligand is perpendicular to the Pt(II) coordination plane; the PtC(carbene) bond distance is 2.01(1) Å and the short C(carbene)-O bond distance of 1.30(1) Å suggests extensive electronic delocalization within the Pt---C(carbene)---O moietry. 相似文献
6.
The solution of [RhCl(PPh3)3] in acidic 1-ethyl-3-methylimidazolium chloroaluminate(III) ionic liquid (AlCl3 molar fraction, xAlCl3=0.67) was investigated by 1H and 31P{1H} NMR. One triphenyl phosphine is lost from the complex and is protonated in the acidic media, and cis-[Rh(PPh3)2ClX], (2), where X is probably [AlCl4]−, is formed. On, standing, 2 is converted to trans-[Rh(H)(PPh3)2X], (3). The reaction of 2 and H2 also produces trans-[Rh(H)(PPh3)2X], (3). 1H and 31P{1H} NMR support the suggestion that a weak ligand such as [AlCl4]−, present in solution may interact with the metal centre. When [RhCl(PPh3)3] is dissolved in CH2Cl2/AlCl3/HCl for comparison, two exchanging isomers of what is probably [RhH{(μ-Cl)2AlCl2}{(μ-Cl)AlCl3}(PPh3)2], (6) and (7), are formed. 相似文献
7.
Daniel Touchard Salaheddine Guesmi Luc Le Pichon Alain Daridor Pierre H. Dixneuf 《Inorganica chimica acta》1998,280(1-2):118-124
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
8.
The 16-electron complex (CO)4W=C(NMe2)SiPh2Me (1) was photochemically prepared from (CO)5W=C- (NMe2)SiPh2Me. Reactions with selected nucleophiles, having different ligand properties, were performed to test the strength of the intramolecular agostic interaction of one of the phenyl groups, by which 1 is stabilized. The stable complexes cis-(CO)4LW=C(NMe2)SiPh2Me were formed with L=P(OMe)3, P(OEt)3 or 2,6-Me2C6H3NC. The substituted complexes had no tendency for ligand elimination. Addition of acetonitrile or pyridine to an ether solution of 1 resulted in the formation of cis-(CO)4(MeCN)W=C(NMe2)SiPh2Me or cis-(CO)4(C5H5N)- W=C(NMe2)SiPh2Me, respectively. These reactions were reversed on evaporation of the solutions. No reaction was observed with triethylamine. 相似文献
9.
M. Teresa A. R. S. Costa Joo J. R. Fraústo da Silva Armando J. L. Pombeiro Rino A. Michelin Gabriella Bombieri Franco Benetollo 《Inorganica chimica acta》1998,280(1-2):308-315
Treatment of a THF solution of trans-[ReCl(N2)L4] (L = PMePh2) with a cyanamide, NCNR2 (R = Me, Et or H) or with cyanoguanidine, NCNC(NH2)2 , yields mer-[ReCl(N2)(NCNR2)L3] (1) or mer-[Re(N2)[Re(N2){NCNC(NH2)2}2L3]Cl (2), respectively, which, to our knowledge, are the first mixed dinitrogen-cyanamide-type complexes to be reported. The former products (1, R=Me or Et) can also be obtained from reaction of the benzoyldiazenido complex [ReCl2(NNCOPh)L3] with NCNR2 in refluxing methanol; the Re(II) complex mer-[ReCl2(NCNEt2)L3] (3) is also formed (conceivably via an unusual homolysis of the C---N bond of the benzoyldiazenido ligand) and its crystal structure is reported. It shows an unusual pyramidal conformation at the amine N atom of the diethylcyanamide ligand which also exhibits a significant structural trans influence on the phosphine, behaving as a stronger net electron donor than the latter ligand. 相似文献
10.
Xiang-Yang Liu Soraya Bouherour Heiko Jacobsen Helmut W. Schmalle Heinz Berke 《Inorganica chimica acta》2002,330(1):250-267
Lewis acid adducts of the hydrides cis- and trans-Re(CO)(PMe3)4H (1) and (2), mer-Re(CO)2(PMe3)3H (3), fac-Re(CO)2(PMe3)3H (4) and trans-Re(CO)3(PMe3)2H (5) were studied with BH3 and 9-borabicyclo[3,3,1] norbonane (BBNH). Using BH3·THF and (BBNH)2 1 and 2 afforded Re(CO)(PMe3)3(η2-BH4) (6) and Re(CO)(PMe3)3(η2-BBNH2) (7) as stable and isolable products. VT IR studies established for the reaction to 7 that BBNH first attaches in a pre-equilibrium to the OCO atom of 1 or 2. At higher temperatures ReH adduct formation occurs with instantaneous transformation to 7 and elimination of PMe3·BBNH. In a similar way, the hydrides 3 and 4 were converted with BH3·THF and (BBNH)2 to yield the stable complexes Re(CO)2(PMe3)2(η2-BH4) (8) and Re(CO)2(PMe3)2(η2-BBNH2) (9). The intermediacy of the η1-BH4 adducts mer-/fac-Re(CO)2(PMe3)3(η1-BH4) was confirmed by VT 1H, 31P NMR and VT IR experiments. The conversion of 5 with BH3·THF led to equilibria with adducts at the OCO terminus in trans position to H and with HRe as revealed by VT IR studies. Temperature dependent 31P equilibrium studies allowed to calculate ΔH=−4.9 kcal mol−1 and ΔS=+0.034 e.u. for this reaction. These adducts could not be isolated. Compound 5 does not react with (BBNH)2 even at elevated temperatures. DFT calculations were carried out to support the structures of the BH3 adducts of 5. In addition a vibrational analysis helped to unravel the IR band assignments of the involved compounds. DFT calculations on 8 confirmed its C2v structure. X-ray diffraction studies were carried out on single crystals of 6 and 7. 相似文献
11.
Cis(or trans)-[RuCl2(CO)2(PPh3)2] react with two and one equivalents of AgBF4 to give the recently reported [Ru(CO)2(PPh3)2][BF4]2·CH2Cl2 (1) and novel [RuCl(CO)2(PPh3)2][BF4] · 1/2 CH2Cl2 (2), respectively. Cis-[RuCl2(CO)2(PPh3)2] also reacts with two equivalents of AgBF4 in the presence of CO to give [Ru(CO)3(PPh3)2][BF4]2 (3). Reactions of 1 and 2 with NaOMe and CO at 1 atm produce the carbomethoxy species [Ru(COOMe)2(CO)2(PPh3)2] (4) and [RuCl(COOMe)(CO)2(PPh3)2] (5), respectively. Complex 4 can also be formed from the reaction of 3 with NaOMe and CO. Alternatively, 4 is formed from cis-[RuCl2(CO)2(PPh3)2] with NaOMe and CO at elevated pressure (10 atm); if these reactants are refluxed under 1 atm of CO, [Ru(CO)3(PPh3)2] is the product. The reaction of [RuCl(CO)3(PPh3)2][AlCl4] with NaOMe provides an alternative route to the preparation of 5, but the product is contaminated with [RuCl2(CO)2(PPh3)2]. Compounds 1. 2, 4 and 5 have been characterised by IR, 1H NMR and analysis, whilst the formulation of 3 is proposed from spectroscopic data only. This account also examines the reactivity of [Ru(CO)2(PPh3)2][BF4]2 · CH2Cl2 with NaBH4, conc. HCl, KI and, finally, MeCOONa in the presence of CO. The products of these reactions, namely cis-[RuH2(CO)2(PPh3)2], cis-[RuCl2(CO)2(PPh3)2], cis-[RuI2(CO)2(PPh3)2] and [Ru(OOCMe)2(CO)2(PPh3)2], have been identified by comparison of their spectra with previous literature. 相似文献
12.
Patrick W. Blosser Mario Calligaris David G. Schimpff Andrew Wojcicki 《Inorganica chimica acta》2001,320(1-2):110-116
Reactions of [(PPh3)2Pt(η3-CH2CCPh)]OTf with each of PMe3, CO and Br− result in the addition of these species to the metal and a change in hapticity of the η3-CH2CCPh to η1-CH2CCPh or η1-C(Ph)=C=CH2. Thus, PMe3 affords [(PMe3)3Pt(η1-C(Ph)=C=CH2)]+, CO gives both [trans-(PPh3)2Pt(CO)(η1-CH2CCPh)]+ and [trans-(PPh3)2Pt(CO)(η1-C(Ph)=C=CH2)]+, and LiBr yields cis-(PPh3)2PtBr(η1-CH2CCPh), which undergoes isomerization to trans-(PPh3)2PtBr(η1-CH2CCPh). Substitution reactions of cis- and trans-(PPh3)2PtBr(η1-CH2CCPh) each lead to tautomerization of η1-CH2CCPh to η1-C(Ph)=C=CH2, with trans-(PPh3)2PtBr(η1-CH2CCPh) affording [(PMe3)3Pt(η1-C(Ph)=C=CH2)]+ at ambient temperature and the slower reacting cis isomer giving [trans-(PPh3)(PMe3)2Pt(η1-C(Ph)=C=CH2)]+ at 54 °C . All new complexes were characterized by a combination of elemental analysis, FAB mas spectrometry and IR and NMR (1H, 13C{1H} and 31P{1H}) spectroscopy. The structure of [(PMe3)3Pt(η1-C(Ph)=C=CH2)]BPh4·0.5MeOH was determined by single-crystal X-ray diffraction analysis. 相似文献
13.
William Henderson Brian K. Nicholson Clifton E. F. Rickard 《Inorganica chimica acta》2001,320(1-2):101-109
The reaction of cis-[PtCl2(PPh3)2] with trisubstituted thioureas [R1R2NC(=S)NHR3] in refluxing methanol with triethylamine base, followed by addition of NaBPh4 gives the salts [Pt{SC(=NR1R2)NR3}(PPh3)2]BPh4 in high yield; a range of thiourea substituents, including chiral, fluorescent and chromophoric groups can be incorporated. The azo dye-derived complex [Pt{SC(=N(CH2CH2)2O)NC6H4N=NC6H4NMe2}(PPh3)2]BPh4 has been characterised by a single-crystal X-ray diffraction study. The formation of a fluorescein-derivatised platinum–thiourea complex is also described. Reaction of cis-[PtCl2(PPh3)2] with PhNHC(S)NHPh or EtNHC(S)NHEt, triethylamine and NaBPh4 gives, respectively, [Pt{SC(=NHPh)NPh}(PPh3)2]+ and the known cation [Pt{SC(=NHEt)NEt}(PPh3)2]+, isolated as tetraphenylborate salts. Reaction of cis-[PtCl2(PPh3)2] with an excess of Na[MeNHC(S)NCN] in methanol gives the bis(thiourea monoanion) complex trans-[Pt{SC(=N---CN)NHMe}2(PPh3)2], characterised by NMR spectroscopy and an X-ray crystal structure determination. When cis-[PtCl2(PPh3)2] is reacted with 1 equiv. of Na[MeNHC(S)N---CN] in methanol, with added NaBPh4, a mixture of isomers of the [Pt{SC(=NHCN)NMe}(PPh3)2]+ cation is obtained. 相似文献
14.
V. Sreenivasa Reddy Kattesh V. Katti Charles L. Barnes 《Inorganica chimica acta》1995,240(1-2):367-370
The water-soluble bisphosphine, 1,2-bis(bis(hydroxymethyl)phosphino)ethane (1), was synthesized in near quantitative yield by the reaction of bisphosphine, H2PCH2CH2PH2, with an aqueous formaldehyde in the presence of K2PtCl4. The reaction of this water-soluble bisphosphine 1 with cis-Pt(COD)Cl2 affords the mononuclear bischelate complex, [Pt{(HOH2C)2PCH2CH2P(CH2OH)2}2](Cl)2 (2), in near quantitative yield. The new ligand and complex have been characterized spectroscopically and the structure of the metal complex, 2, was determined by X-ray crystallography. The Pt(II) complex 2 crystallizes in the orthorhombic space group Pbca(a=14.623(1), B=16.216(2), C=9.319(4) Å) with Z=4. The final R value is 0.024. 相似文献
15.
Janet L Wedgwood Ann P Hunter Roman A Kresinski Andrew W.G Platt Bridget K Stein 《Inorganica chimica acta》1999,290(2):743-196
The reactions of the alkylsulfonated phosphines LM=Ph2P(CH2)nSO3Na/K (n=2, 3, 4) with K2PtCl4 and K2PdCl4 have been studied in homogeneous aqueous solution as a function of pH. In homogeneous acidic solution the protonated phosphines react to give cis- and trans-PtCl2(LH)2. The biphasic reaction between 1,5-cyclooctadiene platinum(II) chloride in dichloromethane and acidified aqueous LNa/K gives a higher proportion of the cis isomer. In neutral solution the initial reaction to give [PtCl(LNa/K)3]+Cl− is followed by slow formation of cis-PtCl2(LNa/K)2. K2PdCl4 reacts more rapidly to give PdCl2(LNa/K)2. In homogeneous alkaline solution rapid oxidation of the phosphine occurs with only small amounts of platinum complex being observable. The biphasic reaction yields phosphine oxide in the aqueous layer and a small amount of the chelate complexes PtL2 in the organic. Representative complexes have been isolated and characterised and the mechanisms for the reactions discussed. The electrospray mass spectra of solutions of the isolated complexes have been recorded in both positive and negative ionisation modes. The positive ionisation spectra are complicated, but platinum and palladium containing ions derived from loss of chloride, H+ and HCl are observed in the negative ionisation spectra. 相似文献
16.
The thermal and photochemical reactions of CpRe(PPh3)2H4 and CpRe(PPh3)H4 (Cp = η5-C5H5) with PMe3, P(p-tolyl)3, PMe2Ph, DMPE, DPPE, DPPM, CO, 2,6-xylylisocyanide and ethylene have been examined. While CpRe(PPh3)2H2 is thermally inert, it will undergo photochemical substitution of one or two PPh3 ligands. With ethylene, substitution is followed by insertion of the olefin into the C-H bond of benzene, giving ethylbenzene. CpRe(PPh3)H4 undergoes thermal loss of PPh3, which leads to substituted products of the type CpRe(L) H4. Photochemically, reductive elimination of dihydrogen occurs preferentially. The complex trans-CpRe(DMPE)H2 was structurally characterized, crystallizing in the monoclinic space group P21/n (No. 14) with a = 6.249(6), b = 16.671(8), c = 13.867(7) Å, β = 92.11(6)°, V = 1443.7(2.9) Å and Z = 4. The complex trans-CpRe(PMe2Ph)2H2 was structurally characterized, crystallizing in the monoclinic space group P21/n (No. 14) with a = 7.467(3), b = 23.874(14), c = 11.798(6) Å, β = 100.16(4)°, V = 2070.2(3.4) Å3 and Z = 4. 相似文献
17.
Jian-Qing Tao Zhi-Guo Gu Tian-Wei Wang Qiao-Fang Yang Jing-Lin Zuo Xiao-Zeng You 《Inorganica chimica acta》2007,360(15):4125-4132
Two new spin-crossover complexes, [Fe(Medpq)(py)2(NCS)2] · py · 0.5H2O (1) and [Fe(Medpq)(py)2(NCSe)2] · py (2) (Medpq = 2-methyldipyrido[3,2-f:2′,3′-h]-quinoxaline, py = pyridine), have been synthesized. The crystal structures were determined at both room temperature (298 K) and low temperature (110 K). Complexes 1 and 2 crystallize in the orthorhombic space group Pbca and monoclinic space group P21/n, respectively. In both complexes, the distorted [FeN6] octahedron is formed by six nitrogen atoms from Medpq, the trans pyridine molecules and the cis NCX− groups. The thermal spin transition is accompanied by the shortening of the mean Fe–N distances by 0.194 Å for 2. The mononuclear [Fe(Medpq)(py)2(NCS)2] and [Fe(Medpq)(py)2(NCSe)2] neutral species interact each other via π-stacking, resulting in a one-dimensional extended structure for both 1 and 2. There exist C–HX (X = S, Se) hydrogen bonds for both complexes. Variable-temperature magnetic susceptibility measurements and Mössbauer spectroscopy reveal the occurrence of a gradual spin transition. The transitions are centered at T1/2 = 120 K for 1 and T1/2 = 180 K for 2, respectively. 相似文献
18.
Reactions of cct-RuH(SR)(CO)2(PPh3)2 (1) (cct = cis, cis, trans) with R′SH provide cct-RuH(SR′)(CO)2(PPh3)2 (R = alkyl, aryl): based on described kinetic data, the proposed mechanism involves PPh3 loss, coordination of R′SH, intramolecular protonation of RS− by R′SH, and RSH elimination. The intramolecular protonation step circumvents a potentially slow RSH reductive elimination step. A similar mechanism is proposed for the thiol exchange reactions of cct-Ru(SR)2(CO)2(PPh3)2 (2). A corresponding dissociative mechanism is also proposed for the reaction of 1 with P(p-tolyl)3, which gives cct-RuH(SR)(CO)2(PPh3)(P(p-tolyl)3) and cct-RuH(SR)(CO)2− (P(p-tolyl)3)2. Other reactions described include the reactions of 1 with H2, CO, HCl and PPh3, and the reactions of 2 with P(p-tolyl)3 and H2. Exposure to light causes 2 to dimerize in solution. 相似文献
19.
Reactions of RhCl(cod)(THP) (cod = 1,5-cyclooctadiene; THP = P(CH2OH)3) with PMePh2 or PCyPh2 (Cy = cyclohexyl) in acetone/MeOH solution under H2 surprisingly form the complexes cis, mer-Rh(H)2Cl(PRPh2)3 (R = Me or Cy); both complexes are characterized by crystallography (the first structures in which the hydride ligands of such dihydrido-chloro-trisphosphine complexes have been located), and by detailed 1H and 31P NMR spectroscopy. The key role of the THP in the observed chemistry is discussed. 相似文献
20.
Lenzi Kaden Armando J. L. Pombeiro Yu Wang Ulrich Abram 《Inorganica chimica acta》1995,230(1-2):189-192
The Tc(I) mixed-ligand complex, trans-[Tc(dppe)2(butNC)2](PF6) (dppe=bis(diphenylphosphino)ethane, butNC=tert-butyl-isocyanide) has been prepared from [Tc(tu−S)63+ (tu-S=thiourea) and a mixture of both ligands. The compound crystallizes triclinic in the space group ). The technetium atom has a slightly distorted octahedral coordination sphere with the isocyanide ligands in trans-position to each other. By cyclic voltammetry, at a Pt electrode, trans-[Tc(dppe)2(butNC)2](PF6) undergoes a single electron reversible oxidation at E1/2ox=0.91 V versus SCE. 相似文献