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Sequential radical-anion-initiated reactions of cluster carbonyl complexes (Ru₃(CO)₁₂, H₄Ru₄(CO)₁₂, Co₃(μ-CR)(CO)₉) with isocyanides or Group V donor ligands have given a range of derivatives containing two or more different ligands attached to the cluster; these compounds can be obtained in moderate to high yields by designed syntheses under mild conditions.     

Ruthenium carbonyl complexes with α-substituted oxime derivatives of terpenes as ligands

The reactions of Ru₃(CO)₁₂ with oximes of α-substituted caran-4-one, lemonen-5- and pinan-3-one derivatives were studied. The reactions at elevated temperatures yield binu-clear complexes Ru₂(CO)₄L₂, with two ruthenium atoms bridging two terpenoid ligands (L) through the oxime groups and coordinated additionally to a nitrogen or sulfur atom of the NR₂ or SR groups respectively. The reactions carried out at room temperature in the presense of Me₃NO yield trinuclear complexes Ru₃(CO)₈L₂ with analogous coordination of the terpenoid ligands. In a solution at room temperature these clusters readily transform to binuclear complexes. The NMR spectroscopy shows the stereochemical nonrigidity of the complexes with the S-CH₂-Ph fragment: at room temperature in a solution the benzyl radical undergoes slow rotation about the S-C bond and a change of the conformation of carane and pinane carbocycles occurs more rapidly. The reactions with pinane and carane derivatives are stereospecific yielding only one of the possible diastereoisomers. More flexible limonene derivative form both diastereoisomers.     

Water-Soluble Organometallic Compounds. 8[1]. Synthesis, Spectral Properties, and Crystal Structures of 1,3,5-Triaza-7-phosphaadamantane (PTA) Derivatives of Metal Carbonyl Clusters: Ru3(CO)9(PTA)3 and Ir4(CO)7(PTA)5

The syntheses of Ru₃(CO)₉(PTA)₃ and Ir₄(CO)₇(PTA)₅ were accomplished through the thermal reactions of Ru₃(CO)₁₂ or Ir₄(CO)₁₂ with the water-soluble phosphine, PTA(1,3,5-triaza-7-phosphaadamantane). The ruthenium derivative was shown by X-ray crystallography to consist of a triangular Ru₃ core with three nearly equal Ru–Ru bonds, with each ruthenium atom bearing an equatorially positioned PTA ligand. In Ir₄(CO)₇(PTA)₅ the iridium atoms define a tetrahedron which is bridged on three edges by CO ligands. One basal iridium atom contains two PTA ligands, while the other two basal and the apical iridium atoms each possess one PTA ligand in their coordination spheres. Although, Ru₃(CO)₉(PTA)₃ is only sparingly soluble in pure water, it is very soluble in aqueous solution of pH<4. Indeed the triruthenium cluster can be extracted reversibly between an aqueous and an organic phase (e.g., CH₂Cl₂) by changing the pH of the aqueous phase. On the other hand the more highly PTA substituted cluster, Ir₄(CO)₇(PTA)₅, exhibits good solubility in aqueous solution (pH 7 and below) and a variety of organic solvents. Both cluster derivatives are stable in deoxygenated, aqueous solutions for extended period of time (>24 h).     

Ruthenium‐catalyzed carbonylative cycloaddition reactions involving carbonyl and imino groups as assembling units

This paper describes carbonylative cycloaddition reactions catalyzed by Ru₃(CO)₁₂. Ru₃(CO)₁₂ was found to catalyze an intramolecular Pauson–Khand‐type reaction. Carbonylative cycloaddition reactions involving a carbonyl group in aldehydes, ketones, and esters as a two‐atom assembling unit were also achieved in the presence of Ru₃(CO)₁₂ as the catalyst. The reaction of 5‐hexyn‐1‐al and 6‐heptyn‐1‐al derivatives with CO in the presence of Ru₃(CO)₁₂ resulted in cyclocarbonylation from which bicyclic α, β‐unsaturated lactones were obtained. Intermolecular [2 + 2 + 1] carbonylative cycloaddition of alkenes, ketones, and CO was also catalyzed by Ru₃(CO)₁₂ as the catalyst to give saturated γ‐lactone derivatives. Simple ketones were not applicable, but ketones having a C?O or C?N group at the α‐position served as a good substrate. These reactions could be extended to carbonylative cycloaddition of the corresponding imines leading to γ‐butyrolactam derivatives. The [4 + 1] carbonylative addition of α,β‐unsaturated imines leading to unsaturated γ‐lactams was achieved with Ru₃(CO)₁₂. © 2008 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 8: 201–212; 2008: Published online in Wiley InterScience ( www.interscience.wiley.com ) DOI 10.1002/tcr.20149     

Reactions of isonitriles with [Fe3(CO)12] and [Ru3(CO)12] monitored by electrospray mass spectrometry: structural characterisation of [Fe3(CO)10(CNPh)2] and [Ru4(CO)11(μ3-η-CNPh)2(CNPh)]

The reactions of [Fe₃(CO)₁₂] or [Ru₃(CO)₁₂] with RNC (R=Ph, C₆H₄OMe-p or CH₂SO₂C₆H₄Me-p) have been investigated using electrospray mass spectrometry. Species arising from substitution of up to six ligands were detected for [Fe₃(CO)₁₂], but the higher-substituted compounds were too unstable to be isolated. The crystal structure of [Fe₃(CO)₁₀(CNPh)₂] was determined at 150 and 298 K to show that both isonitrile ligands were trans to each other on the same Fe atom. For [Ru₃(CO)₁₂] substitution of up to three COs was found, together with the formation of higher-nuclearity clusters. [Ru₄(CO)₁₁(CNPh)₃] was structurally characterised and has a spiked-triangular Ru₄ core with two of the CNPh ligands coordinated in an unusual μ₃-η² mode.     

Thermal decomposition of some ruthenium carbonyl hydrides

The thermal stability of α-H₄Ru₄(CO)₁₂, H₄Ru₄(CO)₁₀P₂, H₄Ru₄(CO)₉P₃, H₄Ru₄(CO)₈P₄ (where P=triphenylphosphine) has been investigated by differential scanning calorimetry and by thermogravimetric analysis under argon dynamic atmosphere.The TG curves of the triphenylphosphine substituted derivatives of α-H₄Ru₄(CO)₁₂ suggest the release of the carbonyl and of the phenyl groups through a not well-defined pattern and overlapping decomposition reactions up to the retention of phosphorus in the residue, while α-H₄Ru₄(CO)₁₂ decomposes to metallic ruthenium. The decomposition heat of α-H₄Ru₄(CO)₁₂ and the isomerization heat of H₄Ru₄(CO)₈P₄ have been evaluated.     

Structure,Stereochemistry and Dynamics of Tetranuclear Polyhydride Clusters Containing Chiral Heterobidentate Phosphanes

A novel chiral phosphane (S)‐2‐(4‐isopropyl‐2‐oxazoline‐2‐yl)phenyl‐di‐N‐pyrrolylphosphane (S‐PyrPOx) based on asymmetric oxazoline ring has been prepared and characterised. Reaction of this ligand and its phenyl‐substituted analogue (S‐PhPOx) with H₄Ru₄(CO)₁₂ and H₃RhOs₃(CO)₁₂ gave substituted derivatives H₄Ru₄(CO)₁₀(1,1‐PhPOx) ( 2 ), H₄Ru₄(CO)₁₀(1,1‐PyrPOx) ( 3 ), and H₃RhOs₃(CO)₁₀(1,1‐PyrPOx) ( 4 ), which were structurally characterised by X‐ray crystallography in solid state and by a variety of multinuclear NMR spectroscopic measurements in solution. In all studied clusters the coordinated ligands form five‐membered chelate rings through phosphorus and nitrogen atoms of oxazoline moiety to afford a novel chiral center associated with the substituted metal atom. The substitution reactions demonstrate extremely high stereoselectivity, which results in formation of only one diastereomer in all three cases to give S,S isomer in 2 and S,R isomer in 3 and 4 .     

Synthesis and X‐ray Crystal Structures of Ru3(CO)9(μ‐arphos)(L) [L = AsPh3, As(m‐C6H4Me)3, As(p‐C6H4Me)3]

Three new triruthenium clusters, Ru₃(CO)₉(μ‐arphos)AsPh₃ ( 1 ), Ru₃(CO)₉(μ‐arphos)As(m‐C₆H₄Me)₃ ( 2 ), and Ru₃(CO)₉(μ‐arphos)As(p‐C₆H₄Me)₃ ( 3 ) were synthesized via thermal reactions of Ru₃(CO)₁₀(μ‐arphos) with different tertiary arsine ligands [AsPh₃, As(m‐C₆H₄Me)₃, As(p‐C₆H₄Me)₃]. All these complexes were fully characterized by elemental analysis, FT‐IR, NMR spectroscopy, and single‐crystal X‐ray diffraction.     

Dreizentren-oxidative Addition von Phosphor-Yliden an Ru3(CO)12

Three-Centre Oxidative Addition of Phosphorus Ylides to Ru₃(CO)₁₂ Phosphorus ylides undergo oxidative addition to Ru₃(CO)₁₂ to yield a wide range of Ru₃ clusters with triply bridging organic ligands derived from the ylides. Ph₃PCH₂ forms HRu₃(CO)₉(μ₃1-Ph₃P — CH — CO) ( 1 ) containing a phosphonio enolate. Ph₃PCH — CHO yields a product mixture containing the phosphonio enolate-bridged cluster and its PPh₃ derivative 6 , the phosphoniomethylidyne-bridged compound H₂Ru₃(CO)₉(μ₃1-C — PPh₃) ( 5 ), and the ketenylidene-bridged compound H₂Ru₃(CO)₈(PPh₃)(μ₃1-C — CO) ( 7 ). Thermal treatment converts the phosphonio enolate ligand (in 1 ) into the phosphoniomethylidyne ligand (in 5 ), and the latter into the ketenylidene ligand (in 7 ). With Ph₃PCH — C(O)Me and Ru₃(CO)₁₂ ortho1-metalated Ru₃ derivatives 10, 11 of the phosphonio ketone R₃P — C — C(O)Me are produced, and likewise with Ph₃PCH — COOEt the ortho1-metalated derivative 12 of the phosphonio ester R₃P — C — CO₂Et. Me₃PCH — COOtBu is oxidatively added to form HRu₃(CO)₉(μ₃1-Me₃P — C — COOtBu) ( 13 ) bearing a phosphonio ester ligand. — The crystal structures of 6 and 13 are reported. The sequence of Ru₃ clusters and the bonding modes of the μ₃ ligands can be related to the surface reactions during Fischer-Tropsch catalysis.     

Monitoring of the formation of binuclear ruthenium carbonyl complexes during reactions by means of high performance liquid chromatography

Reversed-phase high performance liquid chromatography has been used to monitor the reactions of Ru₃(CO)₁₂ with 1,4-diazabutadiene (DAB) and of Ru₂(CO)₆ (DAB) with DAB. The kinetic data show that the formation of an intermediate in the former reaction is the rate determining step, which is first order in Ru₃(CO)₁₂ as well as in DAB. The reactivity depends strongly on the type of substituent on DAB. Exchange of free and coordinated ligands (isopropyl DAB and tert-butyl DAB) is demonstrated in the reaction of Ru₂(CO)₆ (DAB) with DAB. A reversible reaction is proposed to account for this exchange.     

Carbonyl substitution chemistry of some trimetallic transition metal cluster complexes with polyfunctional ligands

The trimetallic clusters [Ru₃(CO)₁₀(dppm)], [Ru₃(CO)₁₂] and [RuCo₂(CO)₁₁] react with a number of multifunctional secondary phosphine and tertiary arsine ligands to give products consequent on carbonyl substitution and, in the case of the secondary phosphines, PH activation. The reaction with the unresolved mixed P/S donor, 1-phenylphosphino-2-thio(ethane), HSCH₂CH₂PHPh ( LH₂), gave two products under various conditions which have been characterised by spectroscopic and crystallographic means. These two complexes [Ru₃(μ-dppm)(H)(CO)₇(LH)] and [Ru₃(μ-dppm)(H)(CO)₈(LH)Ru₃(μ-dppm)(CO)₉], show the versatility of the ligand, with it chelating in the former and bridging two Ru₃ units in the latter. The stereogenic centres in the molecules gave rise to complicated spectroscopic data which are consistent with the presence of diastereoisomers. In the case of [Ru₃(CO)₁₂] the reaction with LH₂ gave a poor yield of a tetranuclear butterfly cluster, [Ru₄(CO)₁₀(L)₂], in which two of the ligands bridge opposite hinge wingtip bonds of the cluster. A related ligand, HSCH₂CH₂AsMe(C₆H₄CH₂OMe), reacted with [RuCo₂(CO)₁₁] to give a low yield of the heterobimetallic Ru-Co adduct, [RuCo(CO)₆(SCH₂CH₂AsMe(C₆H₄CH₂OMe))], which appears to be the only one of its type so far structurally characterised.The secondary phosphine, HPMe(C₆H₄(CH₂OMe)) and its oxide HP(O)Me(C₆H₄(CH₂OMe)) also react with the cluster [Ru₃(CO)₁₀(dppm)] to give carbonyl substitution products, [Ru₃(CO)₅(dppm)(μ₂-PMe(C₆H₄CH₂OMe))₄], and [Ru₃H(CO)₇(dppm)(μ₂,η¹-P(O)Me(C₆H₄CH₂OMe))]. The former consists of an open Ru₃ triangle with four phosphide ligands bridging the metal-metal bonds; the latter has the O atom symmetrically bridging one Ru-Ru bond, the P atom being attached to a non-bridged Ru atom.     

Novel carbonyl complexes of ruthenium with α-substituted oxime derivatives of terpenes

The reactions of Ru₃(CO)₁₂ with 1R,4S,6S-4-dimethylamino-4,7,7-trimethylbicyclo[4.1.0]heptane-3-one oxime (dimethylaminocaraneoxime) (I), 1R,4S,6S-4-methylamino-4,7,7-trimethylbicyclo[4.1.0]heptane-3-one oxime (methylaminocarane oxime) (II), and 1R,2R,5R-2-benzylthio-2,6,6-trimethylbicyclo[3.1.1]heptane-3-one oxime (benzylthiopinaneoxime) (III) were studied. The binuclear complex Ru₂(CO)₄{μ-η³(O,N,X)-L}₂ was formed as the main product in every reaction, when Ru₃(CO)₁₂ was heated with terpenoid to 80°C. In the above complex, two terpene ligands are coordinated in the form of ‘head-to tail’ bridge by the oxime groups at a binuclear metal fragment Ru-Ru. The heteroatom of the second functional group of every bridging ligand (nitrogen of amino group in I and II, sulfur of the thio group in III) is additionally coordinated to the ruthenium atom to give the chelate five-membered ring. Also the reactions of terpenoids I, II, III with Ru₃(CO)₁₂ were performed at room temperature using Me₃NO. In this case, as in the thermal reactions, the main product was the binuclear complex. However, in the reactions of Ru₃(CO)₁₂ with I and II, the trinuclear clusters were isolated that readily transformed to binuclear complexes in a solution. The complexes synthesized can exist as two diasteromers due to their chiral metal core. However, in all the cases, only one diastereomer was isolated, which indicates stereospecific nature of the above reactions. The compounds obtained were characterized by IR, ¹H-, ¹³C{¹H}-, COSY, and HXCOBI-NMR spectroscopy, the specific optical rotation angles were measured. For the binuclear complexes with ligands I, III and for trinuclear cluster with ligand II, single crystals were obtained and studied by X-ray diffraction.     

New Ru3(CO)12 derivatives with bulky diphosphine ligands: synthesis,structure and catalytic potential for olefin hydroformylation

The diphosphine clusters Ru₃(CO)₁₀(dcpm) (1) and Ru₃(CO)₁₀(F-dppe) (2) as well as the bis(diphosphine) clusters Ru₃(CO)₈(dcpm)₂ (3) and Ru₃(CO)₈(F-dppe)₂ (4) have been synthesised from Ru₃(CO)₁₂ and the bulky diphosphines 1,2-bis[bis(pentafluorophenyl)phosphino]ethane (F-dppe) and bis(dicyclohexylphosphino)methane (dcpm). While the single-crystal X-ray structure analyses of 1, 2 and 3 show the expected μ₂-η² coordination of the diphosphine ligands, that of 4 reveals an unusual structure with one μ₂-η²-diphosphine and one μ₁-η²-diphosphine ligand. The clusters 1–4 catalyse the hydroformylation of ethylene and propylene to give the corresponding aldehydes, 2 showing higher activities than those observed for Ru₃(CO)₁₂ and Ru₃(CO)₁₀(dppe).     

Synthesis of <Emphasis Type="Italic">ms</Emphasis>- and β-substituted ruthenium(II) porphyrinates

The reactions of 5,10,15,20-tetraphenylporphine, 2,3,7,8,12,13,17,18-octaethylporphine, and tetra(4-methoxyphenyl)porphine with Ru₃(CO)₁₂ in boiling phenol were studied by spectrophotometry. The following compounds were synthesized and identified: Ru²⁺(CO)(H₂O) 5,10,15,20-tetraphenylporphyrinate, Ru²⁺(CO)(H₂O) 2,3,7,8,12,13,17,18-octaethylporphyrinate, Ru²⁺(CO)(Py) 2,3,7,8,12,13,17,18-octaethylporphyrinate, and Ru²⁺(CO)(H₂O) tetra(4-methoxyphenyl)porphyrinate. The strong electronic effect of the substituents on the reactivity of the tetrapyrrole cycle during the formation of the corresponding porphyrinates was established.     

Cluster chemistry,isocyanide complexes of ruthenium and hydridoruthenium carbonyls: crystal and molecular structure of Ru3(CO)11(CNBu-t)

Reactions between t-BuNC and Ru₃(CO)₁₂ or H₄Ru₄(CO)₁₂ afford Ru₃(CO)_12?n(CNBu-t)_n (n = 1, 2 or 3) and H₄Ru₄(CO)_12?n(CNBu-t)_n (n = 1, 2 or 4), respectively; an X-ray diffraction study of the molecular structure of Ru₃(CO)₁₁(CNBu-t) shows the isocyanide ligand to occupy an axial position, while from the ¹³C NMR spectrum, all CO groups are equivalent at low temperatures.     

Syntheses, structure characterisation and X-ray studies of some mono, di- and tri-substituted cluster complexes of Ru3(CO)12 substituted by bulky fluorinated phosphine ligands

Five trinuclear substituted complexes of the type Ru₃(CO)₁₁L, Ru₃(CO)₁₀L₂ and Ru₃(CO)₉L₃ were synthesised by the reaction of Ru₃(CO)₁₂ with fluorine substituted phosphine ligands, {P(C₆H₄F-m)₃ and P(C₆H₄F-p)₃}, using the radical anion catalysed method. The structures of the resulting clusters were elucidated by means of elemental analyses and spectroscopic methods, which included IR, ¹H, ¹³C and ³¹P NMR spectroscopy. X-ray crystallographic studies of four of the complexes were carried out. In all the complexes, the ligand occupies an equatorial position due to steric reasons, and coordination of the ligand is observed only at the phosphorus atom. In the two monosubstituted complexes, Ru₃(CO)₁₁P(C₆H₄F-m)₃ and Ru₃(CO)₁₁P(C₆H₄F-p)₃, the effect of substitution resulted in an increase in the Ru-Ru distances. Out of the three Ru-Ru bonds, the one which is cis to the ligand is noticeably longer than the other two. The asymmetric unit of the disubstituted complex Ru₃(CO)₁₀{P(C₆H₄F-p)₃}₂ is composed of two molecules, A and B. As expected, the two phosphorus ligands are equatorially bonded to two different ruthenium atoms. The asymmetric unit of the trisubstituted complex is composed of one molecule of Ru₃(CO)₉{P(C₆H₄F-m)₃}₃ and one disordered solvent molecule. The structure consists of one triangular ruthenium complex in which each of the phosphorus ligands is equatorially bonded to three different ruthenium atoms. In the structure, disorder of the fluorine atoms is observed. Bond parameters, especially bond lengths and bond angles, are correlated to the structure and also are compared with the literature data of similar compounds.     

Cluster chemistry: XXXV. Reactions of some ruthenium cluster complexes with hydrogen: Cleavage of element-carbon bonds

Hydrogenation (20 atm, 80°C, 2 h) of trinuclear Ru₃(CO)_12-nL_n (L= tertiary phosphine or phosphite; n = 1–3) resulted in aggregation to give mixtures of H₄Ru₄(CO)12-n(L)_n (n = 0–4), but Ru₃(CO)₁₀(L-L) (L-L=dppm, dpam) gave Ru₃(μ-H)(μ₃-PhECH₂EPh₂)(CO)₉ (E = P, As, respectively) and Ru₃(μ-H)₂(μ₃-PPh)(CO)₈(PMePh₂), and Ru₃(μ-H)(μ₃-SBu^t)(CO)₉ gave Ru₃(μ-H)₂(μ₃-S)(CO)₉ by cleavage of PC, AsC, or SC bonds. Both types of reaction occurred with Ru₃(CO)₁₀(dppe) and [Ru₃(CO)₁₁]₂(μ-dppe).     

Reactions of metal carbonyl cluster complexes with multidentate phosphine ligands; preparation of bis(diphenylphosphino)methane derivatives of the trinuclear complexes M3(CO)12 (M = Fe,Ru and Os) and the X-ray crystal structure of Os3(CO)9(μ-dppm)(η1-dppm) (dppm = Ph2pch2ppH2)

The reaction of bis(diphenylphosphino)methane (dppm) with Fe₃(CO)₁₂ gave the known complexes Fe(CO)₄ (dppm), Fe₂(CO)₇ (dppm), in addition to Fe₂CO)₅(dppm)₂. Two new dppm derivatives of Ru₃CO)₁₂, Ru₃(CO)₉(μ-dppm)(η¹-dppm) and Ru₃(CO)₆(dppm)₃ have been isolated and spectroscopically characterised. From the reaction of Os₃(CO)₁₂ with dppm, the derivatives Os₃(CO)₁₀(dppm), Os₃(CO)₉(μ-dppm)(η¹-dppm) and Os₃(CO)₈(dppm)₂ have been isolated. The crystal structure of Os₃(CO)₉(μ-dppm)(η¹-dppm) has been determined.     

Solid–Gas Hydrogenation of Hex-3-yne and 1,4-Cyclohexadiene in the Presence of the Clusters Ru3(CO)12, H4Ru4(CO)12, H2Ru4(CO)13, and H2FeRu3(CO)13 Supported on Inorganic Materials. Infrared Evidence for Surface Organometallic Reactions

The clusters Ru₃(CO)₁₂ (1), H₄Ru₄(CO)₁₂ (2), H₂Ru₄(CO)₁₃ (3), and H₂FeRu₃(CO)₁₃ (4) supported on pyrex borosilicate glass behave as catalysts for solid–gas hydrogenation reactions of hex-3-yne and 1,4-cyclohexadiene. Their activity and selectivity are discussed. Ru₃(CO)₁₂ (1) was also supported on inorganic oxides, normally used as chromatographic materials or supports for heterogeneous catalysis and characterized by different acidities and surface areas. The observed activities depend on the nature of the inorganic supports; the presence of water also has some influence. Some of these materials were characterized by HRTEM microscopy. Organometallic products have been collected after the catalytic runs both when pyrex and inorganic oxides were used as supports. In particular, the surface organometallic reactions of Ru₃(CO)₁₂ and H₄Ru₄(CO)₁₂ supported on silica have been followed by IR spectroscopy. The nature and role of the arising organometallic compounds are discussed. Our solid–gas results are in good agreement with the mechanisms previously proposed for the hydrogenation of comparable substrates under homogeneous conditions.     

μ-Amido complexes of ruthenium carbonyl. Asymmetric versus symmetric bridging preference of the monodeprotonated derivatives of 1,2-arenediamines. Crystal structure of [Ru3(μ-H)(μ-H3N2-4,5-Me2-1,2-phenylene)]

[Ru₃(CO)₁₂] reacts with 1,2-arenediamines (H₄N₂arene), under CO, to give the very asymmetric clusters [Ru₃(μ-H)(μ-H₃N₂arene)(CO)₉] (arene = 1,2-phenylene (1a) or 4,5-Me₂-1,2-phenylene (1b)) in which the three Ru atoms bear two, three, and four CO ligands, respectively. Under similar conditions, reaction of [Ru₃(CO)₁₂] with 1,8-diaminonaphthalene (H₄N₂naph) leads to break up of the cluster framework to give the binuclear ruthenium(I) compound [Ru₂(μ-H₂N₂naph)(CO)₆] (3). The crystal structure of compound 1b has been determined by an X-ray diffraction study.