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Asymmetric Cyclopropanation of Styrene Catalyzed by Cu–(Chiral Schiff-Base) Complexes

✍ Scribed by Zhengning Li; Guosheng Liu; Zhuo Zheng; Huilin Chen

Publisher
Elsevier Science
Year
2000
Tongue
French
Weight
121 KB
Volume
56
Category
Article
ISSN
0040-4020

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✦ Synopsis

Asymmetric cyclopropanation of olefins was carried out with chiral copper-Schiff base complexes derived from copper acetate monohydrate, substituted salicylaldehydes and a chiral amino alcohol. Substituents on salicylaldehyde framework demonstrate a significant effect on the steroselectivities. Those with electron-withdrawing properties enhance the selectivities, whereas bulky sustituents in ortho position to the phenol hydroxy group decrease the selectivities. An ee of more than 98% was achieved for the reaction of styrene with diazoacetate.

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