Chiral Sulfoxide-Olefin Ligands: Completely Switchable Stereoselectivity in Rhodium-Catalyzed Asymmetric Conjugate Additions
作者:Guihua Chen、Jiangyang Gui、Liangchun Li、Jian Liao
DOI:10.1002/anie.201102586
日期:2011.8.8
it both ways: A novel class of chiral sulfoxide‐olefin ligands was synthesized from a single chiral source. These ligands were evaluated in rhodium‐catalyzed 1,4‐additions of arylboronic acids to electron‐deficient olefins, and remarkable olefin‐directed reversal of stereoselectivity (up to >99 % ee, R isomer; 98 % ee, S isomer) was observed when the reversal ligand pair L1 (branched olefin) and L2
两者兼有:从单一手性来源合成了一类新型的手性亚砜-烯烃配体。在铑催化的芳基硼酸的1,4加成反应中,对这些配体进行了评估,并观察到电子不足的烯烃,并 观察到烯烃定向的立体选择性显着逆转(高达99%ee,R 异构体; 98%ee,S异构体)。当使用反向配体对L1(支链烯烃)和L2(直链烯烃)时(参见方案)。