Phosphine carbonylation

The great majority of platinum(I) complexes are binuclear with monofunctional or bifunctional bridging groups. However, there is also a series of unsupported dimers with the general structure shown in (12). These are generally stabilized by phosphine, carbonyl, and isocyanide ligands.17 Dimeric hydride complexes can have terminal or bridging hydrides and these are discussed above in Section 6.5.2.1.4. 

Tetrahedral complexes du not exhibit geometrical isomerism. However, they are potentially chiral just as is tetrahedral carbon. The simple form of optical isomerism exhibited by most organic enantiomers, namely four different substituents, is rarely observed because substituents in tetrahedral complexes are usually too labile10 for the complex to be resolved, i.e., they racemize rapidly. However, an interesting series of cyclopentadienyliron phosphine carbonyl compounds (see Chapter 15 for further... 

Relevant structural data for selected mixed phosphine carbonyl complexes are shown in Table 5. In all these complexes the nickel(O) atom is four-coordinate in a pseudotetrahedral geometry with the Ni—CO linkage essentially linear, the Ni—C—O angles being in the range 173-178°. In complex (14) the np3 ligand bonds through the three phosphorus atoms and the r. kel is in a pseudotetrahedral environment.103... 

Table S Some Molecular Parameters for Mixed Phosphine-Carbonyl Complexes...

Ohst and Kochi (1986) traced changes in the electron structure that take place during substitution of the triethyl phosphine ligand for the carbonyl ligand in the iron-phenyl-phosphine-carbonyl complex see Scheme 1-50. 

Phosphine-bis(imido) tungsten complexes, associated reactions, 5, 757 Phosphine carbonyl complexes... 

Very recently, the benzannulation has been applied to chromium(phosphine)carbonyl complex 34, which is suited for subsequent immobilization by sol-gel methodology the tri-... 

The hexacarbonylmetalates(-II) of group 4 can be synthesized by reducing the tetrachlorides with potassium in the presence of a cryptand. In the case of hafnium, the starting material is a tertiary-phosphine-carbonyl complex of the zerovalent metal (see equations 52 and 53). The cryptand/(metal cation) system, characterized by a large mass and a low charge density, presumably has a stabilizing effect on the carbonyl anion. Reactions of equations (52) and (53) are carried out with CO at atmospheric pressure. ... 

Carbonylation of different palladium complexes, often in the presence of phosphines, led to the synthesis of a variety of clusters including halocarbonyl clusters of unknown nucle-arity [PdX(CO)] (X = Cl, Br), and phosphine-carbonyl clusters from tetrameric [Pd4(CO)s(PR3)4] to high nuclear-ity compounds such as [Pd38(/r -CO)4(/u. -CO)24(PEt3)i2]. From these preformed clusters, nanosized cluster compounds of higher nuclearity such as [Pd69(CO)36(PEt3)ig] can be prepared. ... 

The photochemistry of transition carbonyl complexes of chromium or iron with phosphirane or l//-phosphirene ligands is studied with time-dependent DFT theory to explore the propensity of the excited metal-phosphine-carbonyl complexes to expel their ligands <2003JA3558>. The complexes of these phosphorus heterocycles show similar behavior as carbonyl complexes with the PH3 ligand and they differ mainly in their enhanced a-donating ability. The calculations point that the excited complexes prefer the expulsion of the phosphorus substituents, which can be an alternative method to demetalate transition metal complexes of organophosphorus compounds. 

Bimetal carbonyl clusters of RhFe were synthesized inside supercages of NaY by reaction of Rh4(CO)i2 with [HFe3(CO)n] /NaY in vacuo at 100°C (262). The pale red-brown RhFe carbonyl clusters in NaY catalyze the hy-droformylation of ethylene and propylene with high selectivity to alcohols, whereas this selectivity is lower for supported pale grey Rh carbonyls and pink-purple Fe carbonyls. With Pd phosphine carbonyl clusters in NaY the hydroformylation of propene displays high selectivity for C7 ketones, which are formed by reaction of propene with the primary hydroformylation product, C4 aldehyde (263). 

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