Alkylation of ketones and thioesters with propargyl and allyl carboxylates

Ivy Zhong

The goal of my project is to determine the effect of electronic and steric differentiation on the electrophile in the allylation reaction of ketones. The electrophile is an allyl cation that has two carbons that could be attacked, shown by the resonance structures illustrated in figure 1. The positive charge on carbon means that the corresponding carbon is electron deficient. A nucleophile, which is a compound that has electrons that could be attracted to the positive charge, reacts with the carbon with a positive charge and forms a bond. However, the full positive charge does not exist on either of the carbon allyl cation because of the resonance. Instead, each of the two carbons bears a partial positive charge, so that the nucleophile may attack with either one. Therefore, my goal for this project is to put different substituents at the R and R' groups to provide a bias to make the nucleophile to choose preferentially one of the two partially charged carbons. This and similar allylation reactions are essential to the synthesis of many biological compounds in living systems.




Wade Downey