Sk. Bertilsson et Pg. Andersson, A rigid dirhodium(II) carboxylate as an efficient catalyst for the asymmetric cyclopropanation of olefins, J ORGMET CH, 603(1), 2000, pp. 13-17
The dirhodium(II) complex 7 of (1S,3R,4R)-2-(p-tert-butylphenylsulphonyl)-2
-aza-bicycol[2.2.1]heptane-3-carboxylic acid (3) (or its enantiomer) was sy
nthesised in four steps from cyclopentadiene, (R)- or (S)-phenylethylamine
and methyl glyoxylate. Complex 7 was evaluated as a catalyst in the asymmet
ric cyclopropanation of alkenes with vinyl- and phenyl-diazoesters, resulti
ng in enantioselectivity of up to 92%. (C) 2000 Elsevier Science S.A. All r
ights reserved.