-WITTIG SIGMATROPIC REARRANGEMENT OF CROTYL PROPARGYL ETHER SYSTEM; AN EMERGING TOOL FOR CONTROL OF ACYCLIC STEREOCHEMISTRY

Article abstract of DOI:10.1016/0040-4020(84)80013-7

The <2,3>-Wittig rearrangement of properly designated (E)- and (Z)-crotyl propargyl ether system has been shown to exhibit a remarkably high degree of threo- and erythro-selection, respectively, and the stereochemical outcomes are discussed on mechanistic grounds.Some useful transformations of the rearrangement product are also described within the context of the formal total synthesis of (+/-)-oudemansin.Further, the high level of diastereoselection is maintained in the reaction of the α-methylcrotyl counterparts, together with the exclusive formation of the (E)-olefinic bond.