Water soluble phosphine complexes

It is to be mentioned that water-soluble phosphine complexes of rhodium(I), such as [RhCl(TPPMS)3], [RhCl(TPPTS)3], [RhCl(PTA)3], either preformed, or prepared in situ, catalyze the hydrogenation of unsaturated aldehydes at the C=C bond [187, 204, 205]. As an example, at 80 °C and 20 bar H2, in 0.3-3 h cinnamaldehyde and crotonaldehyde were hydrogenated to the corresponding saturated aldehydes with 93 % and 90 % conversion, accompanied with 95.7 % and 95 % selectivity, respectively. Using a water/toluene mixture as reaction medium allowed recycling of the catalyst in the aqueous phase with no loss of activity. 

The linear telomerization reaction of dienes was one of the very first processes catalyzed by water soluble phosphine complexes in aqueous media [7,8]. The reaction itself is the dimerization of a diene coupled with a simultaneous nucleophilic addition of HX (water, alcohols, amines, carboxylic acids, active methylene compounds, etc.) (Scheme 7.3). It is catalyzed by nickel- and palladium complexes of which palladium catalysts are substantially more active. In organic solutions [Pd(OAc)2] + PPhs gives the simplest catalyst combination and Ni/IPPTS and Pd/TPPTS were suggested for mnning the telomerizations in aqueous/organic biphasic systems [7]. An aqueous solvent would seem a straightforward choice for telomerization of dienes with water (the so-called hydrodimerization). In fact, the possibility of separation of the products and the catalyst without a need for distillation is a more important reason in this case, too. 

Many of the water-soluble phosphine complexes of the late transition metals that have been synthesized are designed for use as homogeneous... 

For a review on water-soluble phosphine complexes and their application in homogeneous catalysis, see N. Pinault and D. W. Bruce, Coord. Chem. Rev. 241, 1 (2003). 

In general, coordination chemistry of water-soluble phosphine complexes and their reaction with dihydrogen show many similarities to reactions of their water-insoluble analogs. Active hydrogenation catalysts or catalyst precursors, such as... 

It is to be mentioned that water-soluble phosphine complexes of rhodium(I), such as [RhCl(TPPMS)3], [RhCl(TPPTS)3], [RhCl(PTA)3],... 

Selective group transfer is observed from mixed organocuprates of the type (41) acetylenic residues are always retained, and the resulting copper(i) acetylide is produced as its water-soluble phosphine complex (Scheme 101). 

Kiji, J. Okano, T. (1994) 2-Phase catalysis by water-soluble phosphine complexes of palladium, J. Synth. Org. Chem. Jpn., 52,276-84. 

Okano, T. Moriyama, Y. Konishi, H. Kiji, J. (1986) Counter phase transfer catalysis by water-soluble phosphine complexes. Catalytic reduction of allyl chlorides and acetates with sodium formate in two-phase system, Chem. Lett., 1463-6. 

Joo, F. Toth, Z. (1980) Catalysis by water-soluble phosphine complexes of transition metal ions in aqueous and two-phase media, J. Mol CataL, 8,369-83. 

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