1,4-Chirality Transfer via the [2,3]-Wittig Rearrangement of Chiral Allylic Propargyl Ether System. A New, Practical Entry to Chiral Propargylic Alcohols

The [2,3]-Wittig rearrangement of enantiomerically-enriched α-methylallyl propargyl ethers provides a high degree (ca. 90%) of 1,4-chirality transfer, together with 95–98% of (E)-selectivity. The observed sense of 1,4-chirality transfer is discussed on mechanistic grounds.