Reductive Elimination and Pd-Catalyzed Cross-Coupling

Reductive elimination is the reverse of oxidative addition. To illustrate this distinction, consider the following equilibrium  

The forward reaction involves formal oxidation of the metal, accompanied by an increase in coordination number it is an OA. The reverse reaction is an example of RE, which involves a decrease in both oxidation number and coordination number. 

FIGURE 14.7 Reductive elimination of C—S bonds via Pd(ll) complexes with bidentate phosphines with varying bite angles. 

The electronic properties of the ligands also have a large impact on the rates of reductive elimination from Pd(ll) complexes for the formation of carbon-cartxtn and carbon-heteroatom bonds.  

TABLE 14.4 Types of Palladium-Catalyzed Cross-Coupling Reactions 

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