Transition-metal carbonyls reactions with

This method has been more widely used for the synthesis of bridged germylene complexes than for their silicon analogs. The reactions of transition-metal carbonyl monoanions with Me2GeCl2 give A-type bridged... 

IV Carbonyl exchange reaction of an organotin transition metal carbonyl R3SnX with ... 

Propane, 1-propanol, and heavy ends (the last are made by aldol condensation) are minor by-products of the hydroformylation step. A number of transition-metal carbonyls (qv), eg, Co, Fe, Ni, Rh, and Ir, have been used to cataly2e the oxo reaction, but cobalt and rhodium are the only economically practical choices. In the United States, Texas Eastman, Union Carbide, and Hoechst Celanese make 1-propanol by oxo technology (11). Texas Eastman, which had used conventional cobalt oxo technology with an HCo(CO)4 catalyst, switched to a phosphine-modified Rh catalyst ia 1989 (11) (see Oxo process). In Europe, 1-propanol is made by Hoechst AG and BASE AG (12). 

Garbonylation of Olefins. The carbonylation of olefins is a process of immense industrial importance. The process includes hydroformylation and hydrosdylation of an olefin. The hydroformylation reaction, or oxo process (qv), leads to the formation of aldehydes (qv) from olefins, carbon monoxide, hydrogen, and a transition-metal carbonyl. The hydro sdylation reaction involves addition of a sdane to an olefin (126,127). One of the most important processes in the carbonylation of olefins uses Co2(CO)g or its derivatives with phosphoms ligands as a catalyst. Propionaldehyde (128) and butyraldehyde (qv) (129) are synthesized industrially according to the following equation ... 

In addition to the applications reported in detail above, a number of other transition metal-catalyzed reactions in ionic liquids have been carried out with some success in recent years, illustrating the broad versatility of the methodology. Butadiene telomerization [34], olefin metathesis [110], carbonylation [111], allylic alkylation [112] and substitution [113], and Trost-Tsuji-coupling [114] are other examples of high value for synthetic chemists. 

A possible mechanism for the reactions of electrophiles with polynuclear transition metal carbonyls and related complexes. A. R. Manning, Coord. Chem. Rev., 1983, 51, 41-67 (41). 

Reactions of tetrathiastannolanes bearing bulky substituents with groups 6 and 8 transition metal carbonyls have been reported. Tbt(Tip)SnS4 reacts with W(C0)5(THF) in THF at room temperature to give Tbt(Tip)SnS4-W (CO)s in 40% yield (Scheme 64) [144]. 

Three approaches have been tested, as already described above for inorganic supports. The first attempts concern the direct reaction of transition metal carbonyls with unmodified organic polymers like poly-2-vinyl-pyridine.61 62 However, this kind of anchoring is restricted to only a few complexes. Various polymers have been functionalized with donor groups 63-72 ligand displacement reactions using these afforded the corresponding immobilized complexes. Finally, tests with modified complexes and unmodified polymers are scarce because of the low stability of these complexes under the conditions of reactions. 

Coordination chemistry of ER The monomeric fragments E-R are isolobal to carbon monoxide, and many complexes analogous to transition metal carbonyls have been synthesized (41 to 43, see Figure 2.3-7) [68], In most cases these reactions started with those clusters which have a high tendency to dissociate and to form monomers, such as pentamethylcyclopentadienylaluminum(I) or the alkylgal-lium(I) or alkylindium(I) derivatives. Often the products are isostructural to the respective metal carbonyls, but exceptions are the gallium compounds 44 and 45. 

Supercritical fluids allow the formation of species that cannot be made in conventional solvents. For example, rj2-H2 complexes have been generated by direct reaction of hydrogen with a transition metal carbonyl complex [10]. In order to isolate these compounds, a continuous flow reactor was used and such compounds could be isolated with surprising ease. 

Zerovalent transition metal carbonyl moieties may act as electron acceptors, and thus activate coordinated polyene ligands toward nucleophilic attack. Reaction of (C.411<5 )-Fe(CO)3 with KBHEt3 (—80 °C) proceeds via attack at a coordinated carbon monoxide to generate the anionic iron-formyl species 185 (Scheme 47)184. Upon warming to... 

Despite the apparent generality of this Wittig-type process, it must be noted that the reactions of Ph3P=C=PPh3 with transition-metal carbonyl compounds do not always result in the formation of phosphonioacetylide moieties. Thus, replacement of, instead of addition to (see Scheme 24), the CO group has been observed in some... 

Two classes of promoter have been identified for iridium catalysed carbonylation (i) transition metal carbonyls or halocarbonyls (ri) simple group 12 and 13 iodides. Increased rates of catalysis are achieved on addition of 1-10 mole equivalents (per Ir) of the promoter. An example from each class was chosen for spectroscopic study. An Inis promoter provides a relatively simple system since the main group metal does not tend to form carbonyl complexes which can interfere with the observation of iridium species by IR. In situ HP IR studies showed that an indium promoter (Inl3 Ir = 2 1) did not greatly affect the iridium speciation, with [MeIr(CO)2l3] being converted into [Ir(CO)2l4] as the batch reaction progressed, as in the absence of promoter. 

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