Polymer-supported bisBINOL ligands for the immobilization of multicomponent asymmetric catalysts.
[reaction: see text] Polymer-supported bisBINOL ligands were successfully utilized for the immobilization of multicomponent asymmetric catalysts. The polymer-supported Al-Li-bis(binaphthoxide) (ALB) catalyst was more effective than the dendrimer-supported ALB in the Michael reaction of 2-cyclohexen-1-one with dibenzyl malonate affording the adduct in 91% yield with 96% ee. The polymer was also effective for the immobilization of a mu-oxodititanium complex that promoted carbonyl-ene reaction of ethyl glyoxalate with alpha-methyl styrene to provide the adduct with up to 98% ee.
Sekiguti
Tetuya
T
The Institute of Scientific and Industrial Research (ISIR), Osaka University, Mihogaoka, Ibaraki, Osaka 567-0047, Japan.
Iizuka
Yoshimasa
Y
Takizawa
Shinobu
S
Jayaprakash
Doss
D
Arai
Takayoshi
T
Sasai
Hiroaki
H