Ruthenium, complex with

X-ray crystallography, 3, 623 Ruscodibenzofuran synthesis, 4, 698, 709 Ruthenacyclobutane, 3-cyano-synthesis, 1, 667 Ruthenium complexes with pyridines, 2, 124 triazenido, 5, 675 Rutin... 

Many ruthenium complexes with nitrile ligands also feature tertiary phosphines, but simpler complexes can be synthesized [136]... 

The use of chiral ruthenium catalysts can hydrogenate ketones asymmetrically in water. The introduction of surfactants into a water-soluble Ru(II)-catalyzed asymmetric transfer hydrogenation of ketones led to an increase of the catalytic activity and reusability compared to the catalytic systems without surfactants.8 Water-soluble chiral ruthenium complexes with a (i-cyclodextrin unit can catalyze the reduction of aliphatic ketones with high enantiomeric excess and in good-to-excellent yields in the presence of sodium formate (Eq. 8.3).9 The high level of enantioselectivity observed was attributed to the preorganization of the substrates in the hydrophobic cavity of (t-cyclodextrin. 

Berger, I., Hanif, M., Nazarov, A. A., Hartinger, C. G., John, R. O. Kuznetsov, M. L. et al. In Vitro Anticancer Activity and Biologically Relevant Metabolization of Organometallic Ruthenium Complexes with Carbohydrate-Based Ligands. Chemistry Europ. Journal 14, 9046-9057 (2008). 

Fig. 11. Molecular structures of (a) fac-[RuCl3(NH3)3], the first reported ruthenium complex with anticancer activity, and (b) NAMI-A and KP1019, two ruthenium compounds currently in clinical trials.

Ru-vinylidene complexes can be easily prepared by reaction of low-valent ruthenium complexes with terminal acetylenes. Treatment of the Ru(ii) complex 117 with phenylacetylene gave the Ru(iv)-vinylidene complex 118 in 88% yield (Scheme 41 ).60 The reaction of 118 with C02 in the presence of Et3N afforded selectively the Ru-carboxylate complex 120, probably via the terminal alkynide intermediate 119. 

Kinetic studies were carried out by Backvall and coworkers at -54 °C on the hydrogenation of a ketimine, which produces a ruthenium complex with a bound amine (Eq. (46)) [77]. 

BINAP itself has been shown to be effective for the reduction of a,/ -unsatu-rated carboxylic acids [8, 36, 177, 215-220], but Hg-BINAP often provides higher ee-values [193, 194]. The ruthenium complex with P-Phos provides high selectiv-... 

Uemura, T., Zhang, X.Y., Matsumura, K., Sayo, N., Kumobayashi, H., Ohta, T., Nozaki, K. and Takaya, H. J. Org. Chem., 1996, 61, 5510 a classical example is the Monsanto synthesis of (l)-DOPA using ruthenium complexed with the diphosphine DIPAMP, see Classics in Total Synthesis, Nicolaou, K.C. and Sorensen, E.J. VCH, Weinheim, 1996. 

Compounds 81 and 83-86 were linked to P-CD, the ruthenium p-complexes prepared in situ and reductions carried out with the standard substrate 63 (Fig. 26). Comparing the results of ruthenium complexes with ligands 87-91 reveals that any substituent adjacent to the tosyl group leads to modest to good ee values but reduces the reactivity of the catalyst considerably, see 87-89 (Fig. 26), improvement of the 5delds between 33% and 53% was only achieved at elevated temperatures (50°C). In contrast, ruthenium complexes with ligands... 

Another focus of this chapter is the alkynol cycloisomerization mediated by Group 6 metal complexes. Experimental and theoretical studies showed that both exo- and endo- cycloisomerization are feasible. The cycloisomerization involves not only alkyne-to-vinylidene tautomerization but alo proton transfer steps. Therefore, the theoretical studies demonstrated that the solvent effect played a crucial role in determining the regioselectivity of cycloisomerization products. [2 + 2] cycloaddition of the metal vinylidene C=C bond in a ruthenium complex with the C=C bond of a vinyl group, together with the implication in metathesis reactions, was discussed. In addition, [2 + 2] cycloaddition of titanocene vinylidene with different unsaturated molecules was also briefly discussed. 

A variety of alkenylalkylidene ruthenium complexes have been obtained by a quite different route the reaction of alkylidene-ruthenium complex with a functional alkyne via a. [2 + 2] cycloaddition [56]. 

An arene ruthenium complex with polymerizable side chains for the... 

AN ARENE RUTHENIUM COMPLEX WITH POLYMERIZABLE SIDE CHAINS FOR THE SYNTHESIS OF IMMOBILIZED CATALYSTS... 

Ruthenium complexes with Schiff bases were prepared in three steps. 

The anthraquinone exhibits a similar redox behavior as benzoquinone. Thus, redox luminescence switch can also be constructed with fluorophore linked to anthraquinone. For example, the luminescence of molecule 22, a ruthenium complex with an appended anthraquinone moiety, can be reversibly tuned through the interconversion between the anthraquinone and the corresponding hydroquinone.32... 

Chiral ruthenium complexes, with luminescence characteristics indicative of binding modes, and stereoselectivities that may be tuned to the helix topology, may be useful molecular probes in solution for nucleic acid secondary structure36). 

S. Cheng, H. Wan, K. Tsai, andT. Ikariya, Asymmetric transfer hydrogenation of prochiral ketones catalyzed by chiral ruthenium complexes with aminophos-phine ligands, J. Mol. Cat. A Chemical 1999, 147, 105-111. 

Ruthenium complexes with mixed bipyridyl ligands, immobilized inside a Nation film, may also be used as pH-sensitive sensor layers [90]. A completely different approach for a ratiometric imaging of pH sensor foils was developed for diagenetic studies of marine sediments, using the dual fluorescence excitation ratio of the pH-sensitive fluorophore 8-hydroxypyrene-l,3,6-trisulfonic acid (HPTS) [91]. Commonly used dual fluorophors with different absorption and emission maxima in the protonated and basic form for ratiometric measurements are the naphthofluorescein and seminaphthofluorescein derivates (SNARF and SNAFL) [92], It should be noted that ammonia or carbon dioxide can also be detected by some of these pH-sensitive materials [55,93]. 

Levason, W., Quirk, J. J., Reid, G., Smith, S. M., Synthesis, spectroscopic and redox properties of ruthenium complexes with selenoether macrocycles crystal structures of cis-[RuCl2([16]aneSe4)] and trans-[RuCl(PPh3)([16]aneSe4)]PF6 ([16]aneSe4 = 1,5,9,13-tetraselenacyclohexadecane). J. Chem. Soc., Dalton Trans. 1997, 3719-3724. 

A highly regio- and enantio-selective hydroformylation of alkenes, such as PhCH= CH2, CH2=CHCH2CN, and CH2=CHOAc, catalysed by ruthenium complexes with (g) 2,5-disubstituted phospholane ligands has been reported. With (83) as the ligand, the turnover rates over 4000 h-1 at 80 °C, have been attained.108 (Acac)Rh(CO)2-TangPhos [Tangphos = (84)] has been developed as a new enantioselective catalyst for asymmetric hydroformylation of norbornene and other [2.2.1]-bicyclic alkenes (55-92% ee).109... 

A regioselective synthesis of A—methvI tetrazole by alkylation of an unsubstituted tetrazole ruthenium complex with Mel has also been reported <2001JCD3154>. 

Shilov el al. [164] displayed the possibility of synthesizing stable ruthenium complex with molecular nitrogen. 

In view of the protonation and reduction process it is instructive to compare results for Fe(II) compounds with the corresponding data for the positively charged Fe(III) analogues. Iron and ruthenium complexes with two metal centers should be investigated. While the iron complexes model particular features of the FeMo-cofactor in nitrogenase, the ruthenium analogues are analyzed because of their... 

In the example discussed above, the heterotriad consists of a photosensitizer and an electron donor. In the following example, a ruthenium polypyridyl sensitizer is combined with an electron acceptor, in this case a rhodium(lll) polypyridyl center [15]. The structure of this dyad is shown in Figure 6.21 above. The absorption characteristics of the dyad are such that only the ruthenium moiety absorbs in the visible part of the spectrum. Irradiation of a solution containing this ruthenium complex with visible light results in selective excitation of the Ru(ll) center and in an emission with a A.max of 620 nm. This emission occurs from the ruthenium-polypyridyl-based triplet MLCT level, the lifetime of which is about 30 ns. This lifetime is very short when compared with the value of 700 ns obtained for the model compound [Ru(dcbpy)2dmbpy)], which does not contain a rhodium center. Detailed solution studies have shown that this rather short lifetime can be explained by fast oxidative quenching by the Rh center as shown in the following equation ... 

Jakupec MA, Reisner E, Eichinger A, Pongratz M, Arion VB, Galanski M, Hartinger CG, Keppler BK (2005) Redox-active antineoplastic ruthenium complexes with indazole correlation of in vitro potency and reduction potential. J Med Chem 48 2831-2837... 

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