Novel Chiral Dendritic Diphosphine Ligands for Rh(I)-Catalyzed Asymmetric Hydrogenation: Remarkable Structural Effects on Catalytic Properties
journal contributionposted on 29.04.2004, 00:00 by Bing Yi, Qing-Hua Fan, Guo-Jun Deng, Yue-Ming Li, Li-Qin Qiu, Albert S. C. Chan
A series of dendritic ligands with a chiral diphosphine located at the focal point have been synthesized through coupling of pyrphos 2 with Fréchet-type polyether dendron 3. The relationship between the primary structure of the dendrimer and its catalytic properties was established in the Rh-catalyzed asymmetric hydrogenation of α-acetamido cinnamic acid 4. A remarkable structural effect on catalytic activity was observed.