Summary: The anions dervied from allyl vinyl ethers 1 and 2 undergo rapid and highly selective Claisen rearrangements. The degree of asymmetric induction has been found to be uniformly high (ca. 9010) for various substituent patterns but depends markedly on the presence of lithium cations. The absolute sense of asymmetric induction has been established using chiral, nonracemic 1, 3, 2-oxazaphosphorinane 2. Two proposals for the ...
