Transition metal complexes as catalysts

The use of chiral transition-metal complexes as catalysts for stereoselective C-C bond forming reactions has developed into a topic of fimdamental importance. The allyhc alkylation is one of the best known of this type of reaction. It allows the Pd-catalyzed substitution of a suitable leaving group in the allylic position by a soft nucleophile. 

De Vos, D.E., Dams, M., Sels, B.F. and Jacobs, P.A. (2002) Ordered mesoporous and microporous molecular sieves functionalized with transition metal complexes as catalysts for selective... 

The subject of asymmetric synthesis generally (214, 215) gained new momentum with the potential use of transition metal complexes as catalysts. The use of a complex with chiral ligands to catalyze a synthesis asymmetrically from a prochiral substrate is advantageous in that resolution of a normally obtained racemate product may be avoided, for example,... 

In summary, the reduction of ketones and aldehydes can both be performed with MPV and transition-metal complexes as catalysts. Reductions of alkenes, al-kynes, and imines require transition-metal catalysts MPV reductions with these substrates are not possible. 

Organic electroreductive coupling reactions using transition-metal complexes as catalysts have been widely investigated. Reviews on the subject have been published [89, 90]. The method involving the most common transition-metal complexes (nickel, cobalt, palladium) appears to be a useful tool to synthetize heterocycles from organic halides via radical intermediates. Nickel catalyst precursors are nickel(II) salts that are cathodically reduced either to nickel(I) or to nickel(O) and cobalt catalyst... 

Organic Electroreductive Coupling Reactions Using Transition Metal Complexes as Catalysts... 

Organic Electroreductive Coupling Reactions using Transition Metal Complexes as Catalysts Table 2. Reductive electropolymerisation of aryl dihalides using nickel catalysts... 

Nedelec, J.-Y., J. Perichon, and Troupel, M. Organic Electroreductive Coupling Reactions Using Transition Metal Complexes as Catalysts. 185, 141-174 (1997). 

From a historic point of view, metal-catalyzed or metal-promoted hydroamina-tions were first achieved with alkali metals [4]. The use of soluble transition-metal complexes as catalysts for the OHA reaction was pioneered by DuPont workers during the 1970s, the best results being obtained with Rh and Ir salts [5], Later, the finding that electron-rich Ir(I) species cleanly activated N—H bonds to form Ir-amido-hydrido species [6] opened the way to study the reactivity of these amides... 

N d lec J-Y,P richon J,Troupel M (1997) Organic Electroreductive Coupling Reactions Using Transition Metal Complexes as Catalysts. 185 141-174 Nicotra F (1997) Synthesis of C-Glycosides of Biological Interest. 187 55-83 Nishimura J,see Inokuma S (1994) 172 87-118 Nolte RJM,see Sijbesma RP (1995) 175 25-56 Nordahl A,see Carlson R (1993) 166 1-64... 

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