Other Methods for the Generation of Enolates

4 Survey of Reactions between Electrophiles and Enolates and the Issue of Ambidoselectivity 

Enolates and aza enolates are so-called ambident nucleophiles. This term describes nucleophiles with two nucleophilic centers that are in conjugation with each other. In principle, enolates and aza enolates can react with electrophiles either at the heteroatom or at the car-banionic C atom. Ambidoselectivity occurs if one of these alternative modes of reaction dominates. 

Most enolates exhibit an ambidoselectivity toward electrophiles that depends on the electrophile and not on the substrate. The extent of the ambidoselectivity almost always is complete  

2) Essentially all other electrophiles react with the enolate carbon of the enolates of aldehydes, ketones, esters, and amides (important examples are listed in Table 13.5). 

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