An Enantioselective Formal Synthesis of Berkelic Acid
作者:Michael C. McLeod、Zoe E. Wilson、Margaret A. Brimble
DOI:10.1021/ol202265g
日期:2011.10.7
An enantioselective formal synthesis of berkelic acid is described. The key step Involves a late-stage silyl enol ether addition to a benzannulated oxonium ion with subsequent spiroketalization leading to construction of the tetracyclic core. Thermodynamically controlled equilibration under acidic conditions affords the desired spiroketal configuration as a single diastereoisomer.