Chiral Auxiliary Mediated Asymmetric Ireland-Claisen Rearrangements

Chiral Auxiliary Mediated Asymmetric Ireland-Claisen Rearrangements 4.6.6.1 Chiral Clycolates... 

To date the most general chiral auxiliary mediated asymmetric Ireland-Claisen rearrangement is that of Corey et al. (Scheme 4.44) [47]. They found that treatment of crotyl propionates and related esters afforded good yields, diastereoselectivities and enantioselectivities of the pentenoic acid products. The rearrangements also occurred at significantly lower temperature than the silyl ketene acetals. A key advantage of the chemistry is that the chiral auxiliary attachment, Ireland-Claisen rearrangement, and auxiliary removal all occur in one pot. 

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