Catalysis of the Claisen Rearrangement of Aliphatic Allyl Vinyl Ethers

The thermal Claisen rearrangement of allyl vinyl ethers is generally regarded as high-performance method for diastereoselective C−C bond formation. Substrate-induced diastereoselectivity and reagent-induced enantioselectivity with stoichiometric amounts of external chiral auxiliaries have frequently been exploited to control the stereochemical course of the Claisen rearrangement. This review summarizes the attempts to catalyze the Claisen rearrangement of acyclic aliphatic allyl vinyl ethers with chiral and achiral catalysts. The best suited catalysts for the Claisen rearrangement so far identified are Lewis acids. Finally, bis(oxazoline)copper(II) complexes have found a further useful application as chiral catalysts for the first catalytic, enantioselective Claisen rearrangement − 90 years after Ludwig Claisen originally reported a [3,3]-sigmatropic rearrangement of an allyl vinyl ether.