791112-41-9Relevant academic research and scientific papers
Synthesis of the C1-C15 fragment of apicularen A through a regioselective electron-transfer-initiated cyclization reaction
Poniatowski, Alexander J.,Floreancig, Paul E.
, p. 2291 - 2296 (2007)
In this paper we report the preparation of the benzyltetrahydropyran fragment of the vacuolar ATPase inhibitor apicularen A through an oxidative cyclization protocol. In this reaction regioselective cleavage of one homobenzylic ether in the presence of another homobenzylic ether is achieved by selectively weakening one carbon-carbon σ-bond through substitution. This work demonstrates that oxidative fragmentation reactions can be used to generate stable cations selectively, even in the presence of other readily oxidized groups, provided that bond cleavage is sufficiently rapid following oxidation. Georg Thieme Verlag Stuttgart.
Structure-reactivity in relationships in oxidative carbon-carbon bond forming reactions: A mild and efficient approach to stereoselective syntheses of 2,6-disubstituted tetrahydropyrones
Wang, Lijun,Seiders II, John R.,Floreancig, Paul E.
, p. 12596 - 12603 (2007/10/03)
Homobenzylic ethers with pendent enol acetate nucleophiles undergo highly efficient cleavage reactions followed by 6-endo cyclizations to form 2,6-disubstituted tetrahydropyrones with excellent stereocontrol at room temperature in the presence of the mild oxidant ceric ammonium nitrate. Cyclizations proceed through either stabilized or nonstabilized oxocarbenium ions. Structure-reactivity relationships are presented to provide a predictive guide for the design of radical cation cleavage processes. Unique sequences for preparing cyclization substrates based on stereoselective Lewis acid mediated acetal openings have been developed for the synthesis of complex substrates that are suitable for applications to the synthesis of biologically active natural products.
