Carbopalladation palladium salts

To facilitate the coupling reaction of alkenylsilanes, benzenediazonium salts could be employed in place of aryl halides [4], However, the coupling reaction is sometimes accompanied by the formation of regioisomers [Eq.(4)J. This fact is ascribed to a mechanism that involves carbopalladation of an arylpalladium complex to alkenylsilanes followed by elimination of the silyl group and the palladium metal, as is the case in Heck-type reactions. 

These carbopalladation reactions may be divided into two distinct types of reaction those involving palladium(II) salts and those involving organopalladium(ll) complexes. These two reaction types will be treated separately herein. 

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