College of Chemistry, Chemical Engineering and Environmental Engineering , Liaoning Shihua University , Dandong Road West 1 , Fushun , Liaoning 113001 , China.
Jilin Province Key Lab of Green Chemistry and Process , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , 5625 Renmin Street , Changchun 130022 , China.
Org Lett. 2018 Jun 15;20(12):3687-3690. doi: 10.1021/acs.orglett.8b01490. Epub 2018 Jun 6.
A concise synthesis of (-)-hamigeran B and (-)-4-bromohamigeran B is presented. The key reactions include a Suzuki coupling of enol triflate 15 with arylboronic ester for efficient synthesis of the densely 1,2,3-trisubstituted cyclopentene 23, a coordination-controlled intramolecular Friedel-Crafts cyclization of free phenol 13 for highly regioselective construction of tricyclic core 12, and a LiOH/O-promoted hydrolysis and concomitant aerobic oxidation of 31 for atom- and step-economic accessing of diketone 32. The application of these key transformations allowed for a rapid and efficient synthesis of (-)-hamigeran B and (-)-4-bromohamigeran B in 13 steps from the readily available chiral material 18.
呈现了 (-)-hamigeran B 和 (-)-4-溴-hamigeran B 的简洁合成。关键反应包括烯醇三氟甲磺酸酯 15 与芳基硼酸酯的 Suzuki 偶联，以高效合成密集的 1,2,3-三取代环戊烯 23，游离苯酚 13 的配位控制的分子内 Friedel-Crafts 环化，以高区域选择性构建三环核心 12，以及 LiOH/O 促进的水解和伴随的有氧氧化 31，以原子和步骤经济的方式获得二酮 32。这些关键转化的应用允许从易得的手性材料 18 快速高效地合成 (-)-hamigeran B 和 (-)-4-溴-hamigeran B，总步数为 13。
