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Mixed-carbonyl-phosphine complexes

Some of the mixed carbonyl phosphine complexes have been found to be efficient catalysts of oligomerization of alkanes. [Pg.10]

Hydroformylation of PhCH=CHMe in the presence of RhCl(PPh3)3 produces PhCH(CHO)-CHa-CH3 and PhCH3-CH(CHO)-CH3, as well as some PhCH2 CH2 CH3. Both Rh4(CO)i2 and mixed carbonyl-phosphine complexes derived from Rh4(CO)i2 and from Rh,(CO)ie are active catalysts for hydroformylation of alkenes. Acyl-rhodium intermediates may be important when Rh4(COX2 is the catalyst, for [Rh-(C0)2(02CR)]2 dimers have been isolated from alkene hydroformylations in which this polynuclear carbonyl has been the catalyst. Rh4(CO)i2 also catalyses the reaction between ethylene and carbon monoxide, which produces several products, including octane-3,6-dione, undecane-3,6,9-trione, and tetradecane-3,6,9,12-tetraone. The products obtained indicate a mechanism in which addition of ethylene to rhodium and insertion of carbon monoxide into a rhodium-carbon bond alternate. ... [Pg.318]

Apart from Ru(CO)5 and other carbonyls, there are mixed carbonyl-phosphine species and a few simple phosphine complexes like Ru(PF3)5 and Ru[P(OMe)3]5 [61a]. [Pg.20]

A fairly large number of mixed carbonyl phosphine and arsine complexes have been reported so far. They are generally prepared by displacement of CO from Ni(CO)4. Owing to the high stability of Ni(CO)4, when it is reacted with phosphines and arsines at room temperature and atmospheric pressure, only a partial displacement of CO usually occurs. Most of the mixed phosphine (or arsine) carbonyl compounds have the general formula [Ni(CO) (PR3)4 ] (n = 3, 2) and [Ni(CO)2(L—L)] (L—L is a diphosphine or diarsine). These complexes are colourless or yellow-orange solids or liquids. Many of them are thermally stable but decompose in air. The most relevant mixed carbonyl complexes with common phosphines are reported in Table 4. [Pg.10]

Table 4 Mixed Carbonyl Phosphine and Arsine Complexes... Table 4 Mixed Carbonyl Phosphine and Arsine Complexes...
The diarsine and arsine/phosphine analogues of dppm have been used to prepare bridged diplatinum(I) complexes, in both cases with terminal chloro ligands.116,117 Both complexes react with carbon monoxide to produce carbonyl-bridged species. The mixed thio/phosphine ligand Ph2PCH2SMe (PS) also forms a diplatinum(I) complex by conproportionation of its dichloroplat-inum(II) complex with [Pt(dba)2].118 This dimer reacts with carbon monoxide to produce an unsupported dimer [PtCl(PS)(CO)]2 with the thioether arm of the Ph2PCH2SMe unbound. [Pg.687]

Only a limited number of cyano and isocyano complexes and mixed carbonyl, nitrosyl and phosphine cyano complexes of nickel(O) have been described so far.16... [Pg.6]

K4Ni(CN)4 is a yellow solid which is extremely sensitive to oxygen and moisture. It can be prepared by reducing K2Ni(CN)4 in liquid NH3 with an excess of potassium17 and decomposes in water with H2 evolution. CN ions can be easily replaced by ligands with greater jt acceptor properties such as CO, NO and phosphines. Mixed carbonyl and nitrosyl cyano complexes have been prepared by direct reactions (equations 1 and 2).18,19... [Pg.6]

Substitution of CO in the perfluoroalkyl metal carbonyl derivative provides a synthetic route to perfluoroalkyl mixed-carbonyl trifluoro-phosphine metal complexes (method D). [Pg.123]

The carbonyl [Ru3(CO),2] is a good cocatalyst for the low pressure hydroformylation of internal alkenes using the classic rhodium phosphine [HRh(CO)(PPh3),] system in the presence of an excess of triphenylphosphine (P/Rh = 200) (22). Starting from a mixture of hex-2- and hex-3-ene, the addition of [Ru3(CO),2l (Rh/Ru = 1/1) increased both the reaction rate and the n/iso ratio of heptanals. More recently, Poilblanc and coworkers (23) have prepared a mixed ruthenium-rhodium complex formulated as [CIRh(/i-CO)(//-dppm)2Ru(CO)2] (dppm is Ph2PCH2PPh2). This species shows catalytic activity in the hydroformylation of pent-l-ene at 40 bar (H2/C0= 1/1) and 75°C. Conversion to hexanals was 90% in 24 hours and the linearity reached 70%. No further report has appeared to determine the role of the two metals in this catalysis. [Pg.131]


See other pages where Mixed-carbonyl-phosphine complexes is mentioned: [Pg.159]    [Pg.101]    [Pg.157]    [Pg.527]    [Pg.123]    [Pg.303]    [Pg.159]    [Pg.101]    [Pg.157]    [Pg.527]    [Pg.123]    [Pg.303]    [Pg.486]    [Pg.413]    [Pg.74]    [Pg.273]    [Pg.265]    [Pg.16]    [Pg.595]    [Pg.144]    [Pg.595]    [Pg.351]    [Pg.1712]    [Pg.341]    [Pg.365]    [Pg.393]    [Pg.145]    [Pg.435]    [Pg.61]    [Pg.82]    [Pg.184]    [Pg.195]   


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Carbonyl phosphination

Carbonyl phosphines

Mixed carbonyls

Phosphine carbonylation

Phosphines mixed

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