Stereoselective SN1-Type Reaction of Enols and Enolates

Stereoselective alkylation of enolates represents a valuable and important procedure for accessing carbon-carbon-bond frameworks in natural and nonnatural product synthesis. Usually, activated electrophilic partners that react through an SN2 mechanism are employed. To overcome the limitations due to reduced reactivity and steric hindrance, SN1-type reactions can be considered a valid and practical alternative. Accessible enolates can be used in stereoselective (diastereo- or enantioselective) reactions with electrophilic carbenium ions, either used as stable reagents or generated in situ from suitable precursors. The results achieved in this active field are summarized in this review. 1 Introduction 2 Alcohols in SN1-Type Reactions with Enolates 2.1 Enantioselective Reactions with Metal Complexes 2.2 Organocatalytic Enantioselective Reactions 3 Alcohols and Alcohol Derivatives in SN1-Type Reactions with Enolates: Enantioselective Reactions with Metal Enolates 4 Isolated Carbenium Ions in SN1-Type Reactions with Enolates: Enantioselective Reactions with Metal Enolates 5 Miscellaneous 6 Conclusion.