Formal Synthesis of (±)-Pentalenolactone A Methyl Ester

• DOI: 10.1021/acs.joc.9b01349
• Publication Date: 2019-07-12T11:04:38Z
• Authors: Guang-Hao Niu; Pin-Heng Liu; Wei-Chun Hung; Ping-Yao Tseng; Gary Jing Chuang
• Keywords: Formal synthesis

We report the formal synthesis of (±)-pentalenolactone A methyl ester from simple 2-methoxyphenol. The key features our route are as follows: a Diels-Alder reaction masked o-benzoquinone to assemble functionalized bicyclo[2.2.2]octenone, continuous-flow oxa-di-π-methane rearrangement for building diquinane core (AB ring), and an oxidative cleavage/oxidation sequence annulation δ-lactone (C ring).