Hydrocarbyl complexes migration

Insertion of carbon monoxide and alkenes into metal-carbon bonds is one of the most important reaction steps in homogeneous catalysis. It has been found for insertion processes of platinum [16] that the relative positions of the hydrocarbyl group and the unsaturated fragment must be cis in the reacting complex [17], The second issue concerns the stereochemical course of the reaction, insertion versus migration as discussed in Chapter 2.2. 

Because of the importance of the CO insertion into a transihon metal-carbon a-bond in relation to the transition metal-catalyzed carbonylation, the mechanism of the CO insertion has attracted considerable attenhon [1,2]. Through fundamental studies on model complexes, the route of CO insertion has been established for most transition metal complexes to be the one through alkyl migration mechanism [3-8]. While CO insertion can occur with various metal-heteroatom o-bonds, only insertion into metal alkyls (hydrocarbyls) will be discussed in this chapter. 

The migration of the hydrocarbyl ligand to the coordinated Lewis base such as CO, RNC, etc., or CO insertion into the metal-hydrocarbyl bond, usually takes place in the case of 18 complexes via 6e compounds or solvated lie compounds " (see Chapter 2) ... 

Many examples of reactions of complexes containing (tM —C bonds with carbon dioxide are known. The (T-hydrocarbyl ligand may migrate to the carbon atom... 

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