Optically active 1,2-bis(1-arylhydroxymethyl) ferrocene: a new, efficient chiral ligand for scandium-catalyzed asymmetric Diels-Alder reaction.
[reaction: see text] The Sc(OTf)3/FERRODIOL (2) complex was prepared at -78 degrees C in CH2Cl2 in the presence of 2,6-lutidine and MS 4A. The chiral scandium Lewis acid-catalyzed asymmetric Diels-Alder reaction of cyclopentadiene (3) with 3-acyloxazolidin-2-ones (4) effectively produced the adduct (5) in a high yield with good selectivity, i.e., endo/exo = 90:10 up to 91% ee (endo).
Fukuzawa
Shin-ichi
S
Department of Applied Chemistry, Institute of Science and Engineering, Chuo University, Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan. fukuzawa@chem.chuo-u.ac.jp
Fujimoto
Kuniaki
K
Komuro
Yoshitaka
Y
Matsuzawa
Hiroshi
H