Ru/tppts

For the hydrogenation ofpolystyrene-fo-polybutadiene-fo-polystyrene (SBS) block co-polymer with Ru-TPPTS complex as catalyst, Jang et al. [92] applied a poly-ether-modified ammonium salt ionic liquid/organic biphasic system (Fig. 41.3). 

Ir/tppts catalysts exhibit almost the same selectivity as Ru/tppts in the hydrogenation of a,p-unsaturated aldehydes albeit with approximately 70 times lower rates.485 In sharp contrast to the ruthenium and iridium based tppts catalysts, RhJ tppts complexes catalyse the chemoselective hydrogenation of a,fl-unsaturated aldehydes to the corresponding saturated aldehydes (Figure 14, III).54-485... 

Hydrogenation of r/wu-cinnamaldehyde (Figure 14 I Ri=H, R2=Ph) to phenylpropanol (IV Ri=H, R2=Ph) catalysed by Ru/tppms and Ru/tppts proceeds via two different routes in an aqueous/organic two phase system.492 With HRuCl(CO)(tppms)3 the reaction proceeds exclusively via the hydro-cinnamaldehyde III whereas with HRuCl(CO)(tppts)3 both II and III are involved (Figure 14, Ri=H, R2=Ph) 492... 

Osmium complexes modified with tppts and tppms also catalyse the selective hydrogenation of cinnamaldehyde to cinnamylalcohol (Figure 14, II) in an aqueous/organic two phase system.493 The selectivity towards the unsaturated alcohol II with Os/tppts was lower than with Ru/tppts but both Ru and Os/tppts... 

Hernandez and Kalck495,496 synthesized various Ru/tppts complexes and used them as catalysts in the hydrogenation of various cc,J3-unsaturated aldehydes and ketones in a two phase system. Using Ru(H)2(tppts)4 high conversions of cinnamaldehyde (97%) and high selectivity to cinnamylalcohol (95%) were observed under mild reaction conditions (40°C, 20 bar, 3h) 495 More forcing conditions (80°C, 35 bar, 16h) were needed for the hydrogenation of unsaturated a, 3-ketones such as 4-hexen-3-one or benzylideneacetone and only low chemo-selectivities were observed.495... 

Hydrogenation of saturated ketones such as cyclohexanone or 2-butanone catalysed by Ru/tppts complexes gave saturated alcohols in 100% selectivity at 5-99% conversion. 

Hydrogenation of cinnamaldehyde Ru/TPPTS Gas miscibility Enhanced separations Bhanage et al. (1999a)... 

The technique can also be used for the catalytic transfer hydrogenation of carbonyl groups using formate [34, 35] or isopropanol [36] as the hydrogen donor. It is also worth noting, in this context, that Ru/tppts can be used for the selective hydrogenation [37] or transfer hydrogenation [38] of carbohydrates in a monophasic aqueous system (Fig. 7.8). 

Selective hydrogenation of a-/ unsaturated aldehydes Rh-TPPTS or Ru-TPPTS G-L-L/water soluble catalysis [11]... 

Inulin, which is glucose-(fructose) , is nowadays available in large quantities. It seems to be a logical raw material for the preparation of mannitol. Combined hydrolysis and hydrogenation has recently been performed with homogeneous Ru-TPPTS catalyst at pH 2.3 [33], and by use of Ru on acidic carbon as a heterogeneous bifunctional catalyst [34],... 

The catalyst was prepared from an aqueous solution containing both Ru-TPPTS and Pd-... 

Fig. 5.3-5 Structure of a polyether-modified ammonium ionic liquid as used for the hydrogenation of polystyrene-fc-polybutadiene-b- polystyrene (SBS) block copolymer using a Ru/TPPTS catalyst.

Heinen, A.W., Papadogianakis, G., Sheldon, R.A., Peters, J.A., and van Bekkum, H. (1999) Factors effecting the hydrogenation of fructose with a water soluble Ru-TPPTS complex. A comparison between homogeneous and heterogeneous catalysis, J. Mol. Catal. A Chem. 142,17-26. 

The same reactions are also catalyzed by Ru-TPPMS or Ru-TPPTS catalysts however, under comparable conditions, rather low activity (TOF 2.5 h ) was observed. Addition of nitrogen bases (quinoline, aniline) resulted in significantly increased reaction rates. 

Several polymeric materials, such as polybutadiene (PDB), nitrile-butadiene rubber (NBR), styrene-butadiene rubber (SBR), and polyst3rrene-6-polybutadiene-6-polystyrene (SBS) were hydrogenated in toluene-IL biphasic systems with [RhCKTPPTSls] (273) and Ru/TPPTS catalysts (274) the latter was prepared in situ from RuCls and TPPTS under hydrogen pressure. In all cases, the hydrogenated polymers were easily recovered in the toluene phase while the IL phase retained the catalysts. 

Hernandez and synthesized various Ru/tppts complexes and used... 

Basset et showed that Ru/tppts catalysts exhibit extremely high... 

Chahd, M., Broekhuis, A.A., Heeres, H.J., 2011. Experimental and kinetic modeling studies on the hiphasic hydrogenation of levulinic acid to y-valerolactone using a homogeneous water-soluble Ru-(TPPTS) catalyst. Journal of Molecular Catalysis A Chemical 341 (1), 14—21. 

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