Highly enantioselective Claisen rearrangement of imidates derived from primary allyl alcohols

A highly enantioselective and diastereoselective Claisen rearrangement of N-arylimidates derived from an axially chiral binaphthylamine auxiliary is reported. Upon deprotonation of the imidates with lithium diethylamide, the resultant azaenolates rearrange at 0 degrees C to give anti alpha,beta-disubstituted, gamma,delta-unsaturated N-binaphthyl amides. A iodalactonization/zinc reduction sequence readily converts these amides into the corresponding carboxylic acids of 91-95% ee and allows an efficient recovery of the chiral auxiliary.