Ruthenium diphenyl

Biphenyl is reductively eliminated from a ruthenium diphenyl complex by simply heating the diaryl compound at 85°C. The ruthenium intermediate involved in the reductive elimination can be trapped with phosphine in quantitative yield . 

If a mixture of diphenyl sulphide and the corresponding sulphoxide are treated with osmium tetroxide in boiling ether for 48 hours the sulphide is unchanged whilst the sulphoxide is converted into the sulphone in 96% yield with concomitant production of osmium trioxide140. It thus seems that this method would be useful synthetically for the preparation of sulphones from sulphoxides containing sulphide functionalities. Ruthenium tetroxide may be used in place of osmium(VIII) oxide148. 

Fig. 5.6. Crystal structure of tetrakis-P, P, P P -(4-methylphenyl)-l,l -binaphthyldi-phosphine-1,2-diphenyl-1,2-ethanediamine ruthenium borohydride catalyst. Reproduced from J. Am. Chem. Soc., 124, 6508 (2002), by permission of the American Chemical Society.

Rhodium and ruthenium complexes have also been studied as effective catalysts. Rh(diphos)2Cl [diphos = l,2-bis(diphenyl-phosphino)ethane] catalyzed the electroreduction of C02 in acetonitrile solution.146 Formate was produced at current efficiencies of ca. 20-40% in dry acetonitrile at ca. -1.5 V (versus Ag wire). It was suggested that acetonitrile itself was the source of the hydrogen atom and that formation of the hydride HRh(diphos)2 as an active intermediate was involved. Rh(bpy)3Cl3, which had been used as a catalyst for the two-electron reduction of NAD+ (nicotinamide adenine dinucleotide) to NADH by Wienkamp and Steckhan,147 has also acted as a catalyst for C02 reduction in aqueous solutions (0.1 M TEAP) at -1.1 V versus SCE using Hg, Pb, In, graphite, and n-Ti02 electrodes.148 Formate was the main... 

Annual Volume 71 contains 30 checked and edited experimental procedures that illustrate important new synthetic methods or describe the preparation of particularly useful chemicals. This compilation begins with procedures exemplifying three important methods for preparing enantiomerically pure substances by asymmetric catalysis. The preparation of (R)-(-)-METHYL 3-HYDROXYBUTANOATE details the convenient preparation of a BINAP-ruthenium catalyst that is broadly useful for the asymmetric reduction of p-ketoesters. Catalysis of the carbonyl ene reaction by a chiral Lewis acid, in this case a binapthol-derived titanium catalyst, is illustrated in the preparation of METHYL (2R)-2-HYDROXY-4-PHENYL-4-PENTENOATE. The enantiomerically pure diamines, (1 R,2R)-(+)- AND (1S,2S)-(-)-1,2-DIPHENYL-1,2-ETHYLENEDIAMINE, are useful for a variety of asymmetric transformations hydrogenations, Michael additions, osmylations, epoxidations, allylations, aldol condensations and Diels-Alder reactions. Promotion of the Diels-Alder reaction with a diaminoalane derived from the (S,S)-diamine is demonstrated in the synthesis of (1S,endo)-3-(BICYCLO[2.2.1]HEPT-5-EN-2-YLCARBONYL)-2-OXAZOLIDINONE. 

The 02-sensing materials based on spin-coated n-octyl-triethoxysilane (Octyl-triEOS) / tetraethylorthosilane (TEOS) composite xerogel films was synthesized and investigated99. These sensors were based on the O2 quenching of tris(4,7-diphenyl-l,10-phenanthroline)ruthenium (II)... 

Addition of disulfides to carbon-carbon double bonds is catalyzed by ruthenium complexes (Equation (71)).204 Even relatively less reactive dialkyl disulfides add to norbornene with high stereoselectivity in the presence of a catalytic amount of Cp RuCl(cod). Diphenyl disulfide adds to ethylene and terminal alkenes under identical conditions (Equation (72)). 

Scheme 8.7 Mechanism for the hydrogenation of diphenyl-acetylene catalyzed by ruthenium clusters containing facecapping ampy ligands at (a) low [substrate] [cat] ratios and (b) high [substrate] [cat] ratios (CO ligands omitted for clarity).

Fig. 38.1 Product distribution in the hydrogenation of diphenylacetylene as a function of the pH. [ RuCI2(mtppms)2 2] = 6.6 mg (6.79X10-3 mmol ruthenium), mtppms = 8.1 mg (2.03xlCT2 mmol), diphenyl acetyle ne = 89.1 mg (0.5 mmol), 1 bar H2,...

McCord P, Bard AJ (1991) Electrogenerated chemiluminescence Part 54. Electrogenerated chemiluminescence of ruthenium(II) 4,4 -diphenyl-2,2 -bipyridine and ruthenium(II) 4, 7-diphenyl-l, 10-phenanthroline systems in aqueous and acetonitrile solutions. J Electroanal Chem 318 91-99... 

Dichloro(3,3-diphenyl-2-propenylidene)-6 s-(triphenylphosphine)-ruthenium (compound 22) ... 

The formation of other mono- [27-29] or even bis[alkoxy(alkenyl)allenylidene[ ruthenium complexes [28, 30] from the corresponding ruthenium chlorides and 5,5 -diphenyl-penta-1,3 -diynyl alcohol or trimethylsilyl ether in the presence of methanol (Scheme 3.13) and of the allenylidene complex 18 in the absence of methanol (Scheme 3.13) [30, 31] was also suggested to proceed via pentatetraenylidene intermediates. Neither one of these pentatetraenylidene complexes could be isolated or spectroscopically detected although their formation as an intermediate was very likely. 

TRIS(4,7-DIPHENYL-1,10-PHENANTHROLINE) RUTHENIUM(II) CHLORTOE, [Ru(4,7-Ph2Phen)3]Cl2... 

CI2N6RUC72H48, Ruthenium(II), tris(4,7-diphenyl-1,10-phenantroline)-, chloride,... 

A PHOSPHINO BRIDGED RUTHENIUM CLUSTER NONACARBONYL-n-HYDRIDO-Oi-DIPHENYL-PHOSPHINO)TRIRUTHENIUM(O)... 

HPRuC3 H32, Ruthenium(II), [2-(diphenyl-phosphino)phenyl-C, P](Tt6-bexa-methylbenezene(hydrido-,... 

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