Novel chiral dendritic diphosphine ligands for Rh(I)-catalyzed asymmetric hydrogenation: remarkable structural effects on catalytic properties.
[reaction: see text] 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 alpha-acetamido cinnamic acid 4. A remarkable structural effect on catalytic activity was observed.
Yi
Bing
B
Laboratory of Chemical Biology, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing, China.
Fan
Qing-Hua
QH
Deng
Guo-Jun
GJ
Li
Yue-Ming
YM
Qiu
Li-Qin
LQ
Chan
Albert S C
AS