Concise syntheses of (+)-austrodoral and (+)-austrodoric acid Based on H2O2 mediated oxidative ring contraction

Asymmetric synthesis of the marine nor-sesquiterpenoid (+)-austrodoric acid and (+)-austrodoral in seven and nine steps respectively from Wieland-Miescher ketone was described herein. The synthesis featured an oxidative ring contraction of alpha-formyl cyclic ketone mediated by H2O2 to forge the hydrindane scaffold together with the contiguous quaternary carbon centers simultaneously. (C) 2019 Elsevier Ltd. All rights reserved.