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In an attempt to understand the factors that govern the rates of reaction of the complexes [Pt(en)Cl(NH2R)]+NO3− (en = ethylene diamine) with guanosine monophosphate (dGMP) a series of amine complexes, where R＝C8H9NO2 (benzo[d][1,3]dioxol-5-ylmethanamine) (1), C8H11N (phenethylamine) (2), C7H9N (benzylamine) (3), C6H7N (aniline) (4), C6H6IN (p-iodo-aniline) (5) C3H9NO (2-methoxy-ethylamine) (6) and C6H13N (cyclohexylamine) (7), were synthesized and their reactions with deoxyguanosine monophosphate (dGMP) were followed by 1H NMR. Compound 1 was initially chosen because it showed significant water solubility. Compound 1 reacted quantitatively but slowly with dGMP and a subsequent Transmission Electron Microscopy (TEM) study of the binding 1 to a GATC DNA repeat gave a TEM micrograph that showed selective labeling of DNA at guanine, using a technique that allowed the laying down of a straight single strand of DNA on a carbon platform. The TEM suggested a possible side reaction with adenine and so a study of the reaction of 1 with adenine was performed and showed slow and what appeared to be non-specific binding to deoxyadenosine monophosphate (dAMP). The reactions of compounds 2–7 with dGMP were then studied by 1H NMR and it was found that 2 reacted much faster than 1 with dGMP while the remaining complexes reacted more slowly. No reaction of 2 with dAMP was observed in the same time frame. The ultimate goal of the project was to bind a third row transition metal cluster to guanine and given the effective binding of 1 to DNA the synthesis of the complex [Os3(CO)11PPh2(CH2)2NH2(en)PtCl]NO3 (9) is also reported that contains Pt as a linker to label guanine. The synthesis was performed by reacting Os3(CO)10(CH3CN)2 with Ph2PCH2CH2NH2 which gave an η2 chelate complex Os3(CO)10PPh2(CH2)2NH2 (8). Complex 8 was reacted with [Pt(en)Cl(DMF)]NO3 in a CO atmosphere to give 9. 1H and 195Pt NMR indicate formation of an adduct with dGMP but too slowly to be of use in labeling DNA. The solid-state structure of 8 is also reported. [Copyright &y& Elsevier]

Reactions of Ru3(CO)10(µ-dppf) (1) (dppf = 1,1'-bis(diphenylphosphino)ferrocene), Ru3(CO)10(µ-dppm) (2) (dppm = bis(diphenylphosphino)methane), and the orthometalated derivative Ru3(CO)9{µ3- PPhCH2PPh(C6H4)} (3) with silanes (Ph3SiH, Et3SiH, Ph2SiH2) are reported. Treatment of 1 with Ph3SiH and Ph2SiH2 at room temperature leads to facile Si--H bond activation to afford Ru3(CO)9(µ-dppf)(SiPh3)(µ-H) (4) (60% yield) and Ru3(CO)9(µ-dppf)(SiPh2H)(µ-H) (6) (53% yield), respectively. The reaction of 1 with Ph3SiH has been investigated by electronic structure calculations, and these data have facilitated the analysis of the potential energy surface leading to 4. Compound 1 does not react with Et3SiH at room temperature but reacts at 68 °C to give Ru3(CO)9(µ-dppf)(SiEt3)(µ-H) (5) in 45% yield. Reaction of 2 with Ph3SiH at room temperature yields two new products: Ru3(CO)9(µ-dppm)(SiPh3)(µ-H) (7) in 40% yield and Ru3(CO)6(µ3-O)(µ-dppm)(SiPh3)(µ- H)3 (8) in 15% yield. Interestingly, at room temperature compound 7 slowly reverts back to 2 in solution with decomposition and liberation of Ph3SiH. Complex 8 can also be prepared from the direct reaction between 7 and H2O. Similar reactions of 2 with Et3SiH and Ph2SiH2 give only intractable materials. The orthometalated compound 3 does not react with Ph3SiH, Et3SiH and Ph2SiH2 at room temperature but does react at 66 °C to give Ru3(µ-CO)(CO)7{µ3- PPhCH2PPh(C6H4)}(SiR2R¹)(µ- H)](9, R = R' = Ph, 71% yield; 10, R = R' = Et, 60% yield; 11, R = Ph, R' = H, 66% yield) by activation of the Si--H bond. Compounds 4 and 8--11 have been structurally characterized. In 4, both the dppf and the hydride bridge a common Ru--Ru vector, whereas NMR studies on 7 indicate that two ligands span different Ru--Ru edges. Compound 8 contains a face-capping oxo moiety, a terminally coordinated SiPh3 ligand, and three bridging hydride ligands, whereas 9--11 represent simple oxidative addition products. In all of the compounds examined, the triruthenium framework retains its integrity and the silyl groups occupy equatorial sites. [ABSTRACT FROM AUTHOR]

Abstract: Upon mild heating (60–65°C), electron-deficient [Os3(CO)9(μ3-C7H4NS)(μ-H)] (1) readily adds to the activated alkyne, RChsp sp="0.25" />=CO2Me), to give two isomers of the alkenyl complexes, [Os3(CO)9(μ-C7H4NS)(μ3-RCCHR)] (2 and 3), differing in the orientation of the benzothiazole ligand. In both the alkenyl ligand acts as a five-electron donor binding through both carbons and one of the oxygen atoms of the substituents, which adopt a relative cis disposition. Heating 2 cleanly affords 3 suggesting that the former is the kinetic product and the latter is thermodynamically favoured. At higher temperatures (110°C), 3 rearranges to a third isomer [Os3(CO)9(μ-C7H4NS)(μ-RCCHR)] (4) which differs in the binding mode of the alkenyl ligand and where the alkyne substituents are in a relative trans disposition. A second product of this reaction is [Os3(CO)8(μ-OCH3){μ3-C7H4NSC(R)C}(μ-H)] (5) which results from the loss of two moles of CO, carbon–carbon coupling between hydrocarbyl and benzothiazole ligands and carbon–hydrogen addition to the triosmium centre. All new clusters are characterized by a total of 50 valence electrons and contain two metal–metal bonds as shown by single crystal X-ray diffraction studies. [Copyright &y& Elsevier]

Abstract: Treatment of unsaturated [Os3(CO)8{μ3-Ph2PCH2P(Ph)C6H4}(μ-H)] (2) with t BuNC at room temperature gives [Os3(CO)8(CNBu t )){μ3-Ph2PCH2P(Ph)C6H4}(μ-H)] (3) which on thermolysis in refluxing toluene furnishes [Os3(CO)7(CNBu t ){μ3-Ph2PCHP(Ph)C6H4}(μ-H)2] (4). Reaction of the labile complex [Os3(CO)9(μ-dppm)(NCMe)] (5) with t BuNC at room temperature affords the substitution product [Os3(CO)9(μ-dppm)(CNBu t )] (6). Thermolysis of 6 in refluxing toluene gives 4. On the other hand, the reaction of unsaturated [Os3(CO)9{μ3-η2-C7H3(2-Me)NS}(μ-H)] (7) with t BuNC yields the addition product [Os3(CO)9(CNBu t ){μ-η2-C7H3(2-Me)NS}(μ-H)] (8) which on decarbonylation in refluxing toluene gives unsaturated [Os3(CO)8(CNBu t ){μ3-η2-C7H3(2-Me)NS}(μ-H)] (9). Compound 9 reacts with PPh3 at room temperature to give the adduct [Os3(CO)8(PPh3)(CNBu t ){μ-η2-C7H3(2-Me)NS(μ-H)] (10). Compound 8 exists as two isomers in solution whereas 10 occurs in four isomeric forms. The molecular structures of 3, 6, 8, and 10 have been determined by X-ray diffraction studies. [Copyright &y& Elsevier]

Abstract: Heating [Os3(CO)10(μ-dppm)] (1) with two equivalents of PhSSPh in toluene under reflux provided three new triosmium compounds [(μ-H)Os3(CO)7(μ-SPh){μ3-η4-Ph2PCHP(Ph)C6H4}] (2), [Os3(CO)8(μ-SPh)2(μ-dppm)] (3) and [(μ-H)Os3(CO)7(μ-η2-SC6H4)(μ-SPh)(μ-dppm)] (4) in 20%, 21% and 26% yields, respectively. In contrast, a similar reaction of 1 with two equivalents of PhTeTePh in refluxing toluene gave the binuclear compound [Os2(CO)4(μ-TePh)2(μ-dppm)] (6) in 15% yield, and two 50 electron isomeric compounds 5 and 7 with the formula [Os3(CO)8(μ-TePh)2(μ-dppm)] in 20% and 23% yields, respectively. Thermolysis of 3 at 110°C afforded 4 in 53% yield which on further thermolysis in refluxing octane at 128°C gave 2 in 45% yield. Thermolysis of 3 in refluxing octane also gave 2 in 50% yield. The new compounds, 2–7, were all spectroscopically characterized, and the X-ray structures of 2, 3 and 7 have been determined. Compound 2 contains a bridging SPh ligand and a μ3,η4-Ph2PCHP(Ph)C6H4 ligand, formed by two kinds of C–H activation, including orthometallation of a phenyl group as well as an unusual activation of the methylene group of the dppm ligand. The molecular structure of 3 reveals that two SPh groups span the open Os–Os edge of the Os3 triangle, while the dppm ligand bridges one of the closed Os–Os edges. In compound 7, one TePh group spans the open Os–Os edge, while the other spans one of the two closed Os–Os edges and the dppm ligand bridges the third Os–Os vector. [Copyright &y& Elsevier]

Abstract: Treatment of the electronically unsaturated cluster [(μ-H)Os3(CO)8(Ph2PCH2P(Ph)C6H4)] (1) with HCl gas at ambient temperature in dichloromethane afforded (μ-H)Os3(CO)8(μ-Cl)(μ-dppm) (2) and [(μ-H)Os3(CO)7(η1-Cl)(μ-Cl)2(μ-dppm)] (3). Thermolysis of 2 at 110 °C led to an isomer of 2, 4. A similar reaction of 1 with HBr gas gave [(μ-H)Os3(CO)8(μ-Br)(μ-dppm)] (5) as the only product which does not isomerize at 110 °C. In sharp contrast, treatment of 1 with HF gas gave the protonated species [(μ-H)2Os3(CO)8(Ph2PCH2P(Ph)C6H4)]+ (6). Treatment of 1 with CF3CO2H also gave cation 6 whereas CH3CO2H yielded [(μ-H)Os3(CO)8(μ-η2-CH3CO2)(μ-dppm)] (7). Structures of 2, 3, 4 and 6 were established crystallographically. In 2, both the chloride and the hydride ligands simultaneously bridge the same Os–Os edge and the dppm spans another Os–Os bond whereas in 4, all the three ligands bridge the same Os–Os edge. Compound 3 is comprised of an open Os3 arrangement in which one chloride bridges the open Os⋯Os edge, another chloride and a hydride mutually bridge an Os–Os bond and the third chloride is terminally coordinated to one of the Os atoms of the dppm bridged edge. The cation 6 consists of a triangle of osmium atoms in which the shortest Os–Os edge is bridged by a hydride and the metallated phenyl ring and the longest edge is bridged by another hydride and the diphosphine ligand. [Copyright &y& Elsevier]

The reaction of [Ru3(CO)10(mu-dppm)] (1) with dppmSe at 66 °C affords [Ru3(CO)8(mu-dppm)2] (2), [Ru3(CO)7(mu3-CO)(mu3-Se)(mu-dppm)] (3), [Ru3(CO)5(mu3-CO)(mu3-Se)(mu-dppm)2] (4) and [Ru3(CO)6(mu3-CO)(mu3-Se)(mu-dppm)(mu1-Ph2PCH2P(double bond; length as m-dashO)Ph2)] (5) in 7%, 5%, 9% and 33% yields, respectively. A similar reaction between 1 with dppmS gives [Ru3(CO)7(mu3-S)2(mu-dppm)] (6), [Ru3(CO)7(mu3-CO)(mu3-S)(mu-dppm)] (7) [Ru3(CO)5(mu3-CO)(mu3-S)(mu-dppm)2] (8) and [Ru3(CO)6(mu3-CO)(mu3-S)(mu-dppm)(mu1-Ph2PCH2P(double bond; length as m-dashO)Ph2)] (9) in 8%, 7%, 14% and 35% yields, respectively. Treatment of 1 with PhSeSePh at 66 °C affords the dinuclear compound [Ru2(CO)4(mu-SePh)2(mu-dppm)] (10) in 14% yield. Thermolysis of 5 and 9in refluxing toluene at 110 °C gives 4 and 8, respectively. The molecular structures of 4, 9 and 10 have been determined by single-crystal X-ray diffraction studies. The cores of the new clusters 4, 5, 8 and 9 consist of metal triangles capped by mu3-sulfur or selenium atoms with the bidentate ligand bridging in equatorial positions. In compounds 4 and 8, two bidentate dppm ligands bridge the Ru3 triangle in such a way that each ligand bridges two ruthenium atoms and one Ru-Ru edge remains unbridged. Compounds 5 and 9 contain one bridging dppm ligand and one dangling dppm mono-oxide ligand Ph2PCH2P(double bond; length as m-dashO)Ph2 coordinated to the rear metal atom at an equatorial position. The molecular structure of 10 shows classical "sawhorse" structure with two bridging SePh ligands as well as the dppm ligand. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel Rh-containing non-phosphorous supported catalysts for tandem hydroformylation-hydrogenation were obtained. • Tertiary nitrogen atoms of the polymer anchored on material's surface promote aldehyde hydrogenation over Rh active centers. • Catalysts showed high activity (hydroformylation TOF 206 h−1) and chemoselectivity. • Catalyst K N performed stable hydroformylation yield at least in the first 5 cycles with a decrease in alcohol selectivity. Non-phosphorous rhodium-containing catalysts for direct conversion of olefins to alcohols via tandem hydroformylation/hydrogenation have been designed and synthesized. Interaction between Rh(acac)(CO) 2 and tertiary amino groups on the surface of mesoporous hybrid organic-inorganic supports yielded materials which were successfully used in the tandem process. Data obtained for a selected catalyst K N demonstrate that rhodium is in the Rh+1 state highly dispersed on the surface and is bonded with nitrogen atoms both before and after use. Evaluation of the catalytic performance shows high activity (hydroformylation TOF 312 h−1), chemoselectivity and stable hydroformylation yield at least in the first 5 cycles with a decrease in alcohol selectivity. The influence of temperature, reaction time, total pressure, and molar CO/H 2 ratio of syngas on oxygenate yields is described. Type of the hydroformylation active sites and possible pathways for the observed decrease in hydrogenation are discussed. [ABSTRACT FROM AUTHOR]