The anionic oxy-Cope rearrangements of acyclic 1,5-dien-3-ols, when their stereochemistries are properly designated. are shown to proceed with a high level of diastereoselection and asymmetric transmission. The utility of the acyclic oxy-Cope variants is demonstrated by the stereocontrolled synthesis of the key precursors of (+)-faranal (insect pheromone) and (-)-antirhine (Corynanthe-type indole alkaloid).
Acyclic diastereocontrol and asymmetric transmission via anionic oxy-Cope rearrangement: a synthetic application of sequential [2,3]Wittig-oxy-Cope rearrangements
摘要:
The anionic oxy-Cope rearrangements of acyclic 1,5-dien-3-ols with the 3,4-erythro configuration established by the [2,3]Wittig rearrangement are shown to provide a useful level of diastereoselection and asymmetric transmission in the context of a formal asymmetric synthesis of an insect pheromone.