Progress towards the total synthesis of hamigerans C and D: a direct approach to an elaborated 6-7-5 carbocyclic core
作者:Douglas Charles Duquette、Thomas Jensen、Brian Mark Stoltz
DOI:10.1038/ja.2017.96
日期:2018.2
The hamigeran family of natural products has been the target of numerous syntheticefforts because of its biological activity and interesting structural properties. Herein, we disclose ourefforts toward the synthesis of hamigerans C and D, unique among the initially isolated members because of their 6-7-5 carbocyclic core. Our approach directly targets this tricyclic motif by sequential Negishi and
Ring‐Contraction Strategy for the Practical, Scalable, Catalytic Asymmetric Synthesis of Versatile γ‐Quaternary Acylcyclopentenes
作者:Allen Y. Hong、Michael R. Krout、Thomas Jensen、Nathan B. Bennett、Andrew M. Harned、Brian M. Stoltz
DOI:10.1002/anie.201007814
日期:2011.3.14
Contraction action! A simple protocol for the catalyticasymmetricsynthesis of highly functionalized γ‐quaternaryacylcyclopentenes (see schematic) in up to 91 % overall yield and 92 % ee has been developed. The reaction sequence employs a palladium‐catalyzed enantioselective alkylation reaction and exploits the unusual stability of β‐hydroxy cycloheptanones to achieve a general and robust method