Decarbonylation of Aldehydes Rh

Wilkinson s catalyst mediates the decarbonylation of aldehydes (RCHO — RH + CO). It s quite a remarkable reaction, yet the reaction mechanism is quite simple. Nucleophilic addition of Rh(I) to the aldehyde is followed by a 1,2-hydride shift from C to Rh to give an acyl-Rh(III) complex, the product of an overall oxidative addition to the aldehyde C-H bond. Elimination of CO then gives the 

Metals catalyze a diverse set of reactions, and it is difficult to make generalizations, but some basic principles can be kept in mind. 

No matter what the metal and what the transformation, remember to label the atoms, make a list of bonds to make and break, and obey Grossman s rule  

Palladium complexes are versatile and popular catalysts, catalyzing a wide variety of transformations in good yield under mild conditions. Draw mechanisms for the following Pd-catalyzed reactions. 

Many transition metals other than Pd also catalyze organic reactions. Draw mechanisms for the following metal-catalyzed reactions. 

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