Total Synthesis of Palodesangren B Trimethyl Ether and D Dimethyl Ether via a Late-Stage Formation of 2<i>H</i>-Pyran-2-one of the Tetrahydrobenzo[<i>c</i>]pyranochromenone Core
作者:Kassrin Tangdenpaisal、Poramate Songthammawat、Kornkamon Akkarasereenon、Kanokpish Chuayboonsong、Somsak Ruchirawat、Poonsakdi Ploypradith
DOI:10.1021/acs.joc.9b01596
日期:2019.11.1
steps from the tricyclic core, palodesangren B trimethyl ether and palodesangren D dimethyl ether could be synthesized in 29 and 18% overall yields, respectively. A reaction sequence comprising the regioselective MgCl2-mediated Casnati-Skattebøl ortho-formylation of phenol, Wittig methylenation, acryloylation, and Ru(II)-catalyzed ring-closing metathesis (RCM) led to the formation of the final 2H-pyran-2-one
在三环核的四个步骤中,可以分别以29%和18%的总产率合成palodesangren B三甲基醚和palodesangren D二甲基醚。包含区域选择性MgCl2介导的Casnati-Skattebøl苯酚的甲酰化,Wittig甲基化,丙烯酰化和Ru(II)催化的闭环复分解(RCM)的反应序列导致最终2H-pyran-2-的形成所需四环核的一个环。