Design of a binaphthyl-based axially chiral amino acid as an organocatalyst for direct asymmetric aldol reactions.
A novel and robust binaphthyl-based amino acid was designed and successfully applied to the direct asymmetric aldol reaction. In some cases, this catalyst leads to higher yields and selectivities than the well-known proline catalyst. For instance, the direct asymmetric aldol reaction of acetone with 4-nitrobenzaldehyde in the presence of the binaphthyl-based amino acid catalyst proceeded smoothly to give the aldol adduct in 82% yield with 95% ee. This catalyst was also found to catalyze effectively the reactions of cyclic or unsymmetrical ketones to give the corresponding aldol adducts with excellent diastereo- and enantioselectivities.
Kano
Taichi
T
Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan.
Tokuda
Osamu
O
Takai
Jun
J
Maruoka
Keiji
K
D000596:Amino Acids / Q000737:chemistry*; D002384:Catalysis; D009281:Naphthalenes / Q000737:chemistry*; D013237:Stereoisomerism
D000596:Amino Acids; D009281:Naphthalenes