Monolayer-protected Au cluster (MPC)-supported Ti-BINOLate complex.
[reaction: see text] Disulfides bearing (R)-1,1'-bi-2-naphthol ((R)-BINOL) moieties at each terminal position have been successfully introduced on the surface of Au cluster. Ti-BINOLate complex generated from the obtained monolayer-protected Au cluster (MPC) promoted catalytic asymmetric alkylation of benzaldehyde with Et(2)Zn to afford the adduct in up to 98% yield with 86% ee. After completion of the reaction, the BINOL-functionalized MPC was easily recovered.
The Institute of Scientific and Industrial Research (ISIR), Osaka University, Mihogaoka, Ibaraki, Osaka 567-0047, Japan.
Kazuyoshi
K
Marubayashi
Shinobu
S
Takizawa
Tetsuo
T
Kawakusu
Takayoshi
T
Arai
Hiroaki
H
Sasai