Prochiral Substituents at the Radical Center

In many cases, substituents not bound to a stereogenic center can strongly influence the stereochemistry of a radical process. Two different types of effect will be discussed here the presence of a prochiral substituent at the radical center of enolate radicals and the presence of an amide moiety next to the radical center. 

Giese has investigated this effect in detail and applied it for highly stereoselective synthesis of C-disaccharides [18, 19]. For instance, the radical conjugate addition 

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