Convergent Asymmetric Alkylation from meso and dl Carbonates

Significance

In the presence of a chiral catalyst system for allylic alkylation, meso and dl allylic carbonates generate a single product in excellent yield and enantiomeric excess. The reactions can be performed with either meso or dl compounds, or a combination of the two compounds into one flask to generate the same product. The maximum yield of the dl mixture is 50%, as the R,R-enantio­mer is inactive, whereas the meso compound is completely active; thus a mixture of the two has a maximum yield of 75%.