Oxidative polycyclizations with rhenium(VII) oxides

Abstract

The consecutive oxidative polycyclization reaction with rhenium(VII) oxides represents a highly stereoselective synthetic tool by which polyenes that contain a bis-homoallylic alcohol can be transformed into poly-THF products in a single step. On the basis of a detailed study with model substrates, a set of rules is proposed to predict product configurations in the polycyclization reactions with trifluoroacetylperrhenate. This methodology is exceptionally useful for the synthesis of polyoxygenated carbon skeletons that contain many stereogenic centers, and for the Annonaceous acetogenins in particular. Many of these potent antitumor agents, including solamin, reticulatacin, asimicin, bullatacin, trilobin, trilobacin, squamotacin, rolliniastatin, uvaricin, rollidecins C and D, mucocin, goniocin, and cyclogoniodenin T, as well as chemical libraries of non-natural analogs, were synthesized using the oxidative polycyclization reaction in combination with the Sharpless AD and AE reactions.