Remarkable Effect of Aluminum Reagents on Rearrangements of Epoxy Acylates via Stable Cation Intermediates and Its Application to the Synthesis of (S)-(+)-Sporochnol A

A remarkable effect of (C6F5O)3Al for promoting the rearrangement of epoxy acylates via stable cation intermediates was found, and new methods for constructing chiral benzylic, vinylic, and acetylenic quaternary carbon centers were developed. During the study, the importance of the ionic nature of the O−metal bond in the intermediates of such epoxides was addressed. This method was applied to the asymmetric total synthesis of (S)-(+)-sporochnol A.