Department of Chemistry, Zhejiang University, Hangzhou, 310027, China.
School of Chemical and Environmental Engineering, Wuyi University, Jiangmen, 529020, China.
Angew Chem Int Ed Engl. 2018 Mar 26;57(14):3661-3665. doi: 10.1002/anie.201713106. Epub 2018 Feb 28.
Dibenzocyclooctadiene lignans are an interesting class of molecules because of their unique structure based on an axially chiral biaryl moiety as well as their significant biological activity. Herein, we describe the development of a palladium-catalyzed atroposelective C-H alkynylation and its application in gram-scale, stereocontrolled formal syntheses of (+)-isoschizandrin and (+)-steganone. tert-Leucine was identified as an efficient, catalytic transient chiral auxiliary. A wide range of enantiomerically enriched biaryl compounds were prepared by this approach in good yields (up to 99 %) with excellent enantioselectivity (up to >99 % ee).
二苯并环辛二烯木脂素因其独特的结构（基于轴向手性联芳基部分）以及显著的生物活性而成为一类有趣的分子。在此，我们描述了钯催化的轴手性 C-H 炔基化反应的发展及其在克级规模、立体控制的 (+)-异五味子素和 (+)-五味子酮的形式合成中的应用。叔亮氨酸被确定为一种有效的、催化的瞬态手性辅基。通过这种方法可以制备出多种对映体富集的联芳基化合物，产率高（高达 99%），对映选择性好（高达 >99%ee）。
