Y-enolizable enones

The group of Melchiorre expanded the nature of donors to y-enolizable enones [27], usually considered in organocatalysis as electrophiles, using dienamine activation. Indeed (i-substituted cyclohexenones were activated by chiral primary amine 19 derived from cinchona alkaloid to become a dienamine nucleophilic species that could react with nitroolefins. Among the three dienamines that could be formed after iminium generation (Scheme 34.2), the conditions described by Melchiorre et al. selectively favored thermodynamically the exo dienamine 20. 

Scheme 34.2 Possible functionalizations of y-enolizable enone by dienamine activation.

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